1
ASSESSING THE RELATIONSHIP BETWEEN CRUISE SHIP
DESIGN FEATURES AND LONG-TERM PROFITABILITY
Chapter 1 – Introduction
The purpose of this thesis is to provide an evaluation tool against the impact of the selection of different
design features in the early stages of yacht design. The techniques developed are used to estimate the
physical characteristics and performance of yachts. These techniques are then applied in the Cruise Ship
Analysis Tool (CSAT), which provides a clear and easy-to-use interface for analyzing the characteristics
of the vessel. By utilizing the techniques provided in the CSAT along with the current net worth (NPV)
model, it can be evaluated how the selection of certain design features at the initial design stage affects
the profitability of the yacht.
In the initial design stage, often various dimensions, parameters, quantities, qualities, or other forms of
value are analyzed to distinguish the most profitable project among existing design alternatives. This is
known as the measure of achievement (MOM). The main goal in the shipping industry is to design ships
that support profitability. Profitability, which is defined as the ability to generate profits, is essential for
cruise companies in order to generate the revenue necessary to support their operations. According to
Lamb (2003), "The success of engineering depends heavily on economic success" (pp. 6-3). Therefore,
it is crucial for ship designers to consider the impact of the selection of certain design features at the
initial design stage on the ship's potential profitability if the design is implemented. For example, a
client in the commercial sector who contracts a Naval Architecture firm to design a ship for a specific
purpose, must consider the implications for profitability in selecting design features (such as hull shape
and engine type) to produce a more profitable ship design for their client. This will strengthen the
relationship between the naval architecture firm and the client, while also providing the client with
greater financial resources to strengthen future contracts.
NPV is the most widely used method for analyzing the profitability of potential investments. Its
popularity is due to its ease of use and effectiveness in comparing the cost characteristics of various
design alternatives. The NPV model analyzes a project's profitability by considering the project's net
benefits in a given payback period and project term. Net benefits include construction costs, operating
costs, and revenue generated over the life of the project. The rate of return is the return on an investment
over a specific period expressed as a percentage of the total investment. Typically, the rate of return is
set at the minimum desired level (also called the level of resistance) that the company receives before
starting the project. If the NPV is positive, the project is considered profitable and will most likely be a
profitable investment. On the contrary, a negative NPV indicates that the project is not profitable. The
higher the NPV value, the greater the potential profit from the investment. In the shipping industry, the
rate of return used in the NPV model is usually based on the profitability of cruise ships that have
proven to be economically successful. If the initial yacht design shows a positive NPV with this rate of
return, then it is likely that the design will be as profitable as the yacht is built. Cruise ship companies
such as Carnival Corporation & plc often set minimum rates of return that must be achieved by their
subsidiaries to allow for capacity expansion (Buck & Conrady, 2009).
To analyze the NPV of a yacht at the initial design stage in this thesis, the physical characteristics and
design performance of the yacht were first estimated using the techniques discussed in Chapters 3 and 4.
2
The physical parameters of the yacht design are estimated based on the data of 21 yachts that have been
classified and built, which represent vessels from 12 different cruise lines with varying gross tonnage
(GT) and passenger carrying capacity. Nonetheless, these yachts are not the only source for estimating
the physical characteristics and performance of yacht designs. For example, the design resistance of a
yacht was estimated using model data provided in the publication Ship Resistance – Effect of Form and
Principal Dimensions (Guldhammer & Harvald, 1974).
CSAT is a clearly designed, concise, and user-friendly user interface, built using Microsoft Excel to
analyze the physical characteristics and performance of a yacht in the early design stages. CSAT can
also be used to analyze the profitability of yacht designs by utilizing NPV models. Although the CSAT
was built specifically for the purpose of this thesis, it is comprehensive enough to be used in a variety of
early yacht design analyses due to its ability to estimate the various parameters required to calculate
NPV.
To analyze the implications of the selection of certain design features at the initial design stage on the
profitability of yachts, NPV was analyzed for a limited number of yacht designs with various
combinations of design features using CSAT. The design of the yacht is determined by the passenger
carrying capacity with a capacity of two people per cabin. Design features are defined as limited design
decisions that affect the physical and/or performance of a yacht in some aspect. For example, the
selection of a diesel engine compared to a gas turbine engine can affect the performance of a yacht in
terms of fuel consumption and its physique in terms of fuel tank size. The design feature set refers to a
combination of various design decisions that affect the ship as a whole.
By plotting NPV as a function of the yacht's design feature set, the design feature set that provides the
highest NPV can be identified. Designs that use a combination of these design features are considered
the most profitable. Furthermore, this set of design features is compared to analyze the influence of
passenger carrying capacity on cruise ship profitability
3
Chapter 2 – Background
Cruise ships are characterized as vessels that are related to recreational activities (Lamb,
2004).
Usually, the cruise ship returns to the same port from which it departs after the cruise is over.
Cruise ships differ from ocean liners in that the primary mission of ocean liners is to transport
passengers from one port to another (e.g. transatlantic shipping). In 2013, the average length of
a cruise ship was 7.3 days.
The size of a yacht is most often measured and referred to in terms of gross tonnage
(GT). GT is a dimensionless quantity that describes the volume of all enclosed spaces that a
ship has and serves as the basis for ship regulation and the assessment of taxes and fees (Scull,
2007). Although, the actual shape of the GT does not include balconies, sundecks, or similar
areas, cruise line marketing departments will often include these spaces to promote their ships
to be larger, thus promoting ticket sales. Nonetheless, cruise lines will use the actual GT of the
cruise ship when taxes and fees are being assessed as the cost will be less. GT should not be
confused with gross register tonnage measurement (GRT). GT refers to a system of conventions
derived from the provisions of the International Convention on the Measurement of Ship
Tonnage in 1969 (Coast Guard Marine Safety Centre, 2004). GRT refers to a regulatory system
and is calculated in units of 100 ft³ register tonnes per ton. The regulatory system consists of
standard, double, and simple sub-systems. The standard sub-system dates back to the 1860s and
is based on the British "Moorsom" system. The dual sub-system was developed in the mid-20th
century to benefit the holding deck ships as it provided an alternative to installing them with
tonnage openings. A simplified sub-system was passed by Congress in 1966 for recreational
boats to reduce the cost burden for owners and the measurement workload on the government.
The simplified sub-system was later expanded to include specific commercial vessels.
Historically, the average GT among yachts delivered over the past 20 years has
increased every year. This correlation is attributed to cruise ship companies trying to maximize
profits per ship. Figure 1 illustrates the GT of Carnival Cruise Lines, Norwegian Cruise Line,
and Royal Caribbean International yachts plotted for the year of delivery (i.e. between 1990 and
2014).
4
250,000
200,000
Carnival Cruise Lines
Norway Cruise Lines
Royal Caribbean International
150,000
100,000
50,000
0
1990 1995 2000 2005 2010
Year
Figure 1. GT and the year of delivery of the yacht built. Carnival Cruise Lines, Norwegian Cruise Line, and Royal
Caribbean International cruises delivered between 1990-2014 are plotted.
The main types of cruise lines are contemporary, premium, and luxury which are mainly
distinguished by their luxury and space ratio (i.e. GT per passenger). In more detail,
contemporary cruise lines are considered to be full of amenities that offer a plethora of activities
in a relaxed environment of high value ("Cruise Line Types," n.d.). Ships in this type of cruise
line usually have a larger GT when compared to other cruise ships, however, a lower space
ratio. Examples of contemporary cruise lines are Carnival Cruise Lines, Norwegian Cruise Line,
and Royal Caribbean International. Premium cruise lines are typically more luxurious and
elegant than contemporary cruise lines, offering greater space and comfort per passenger in a
semi-formal environment; However, at a greater cost for passengers. Also, they are usually
more refined when it comes to passenger service. Ships in this type of cruise line usually have
medium to large GT when compared to other cruise ships. Examples of premium cruise lines
are Celebrity Cruises, Holland America Line, and Princess Cruises. Luxury cruise lines are
considered more luxurious and elegant than premium cruise lines, offering a formal
environment and personalized service to create a better experience for passengers on and off the
ship. These cruises will usually charge a higher fee for passengers. Ships in this type of cruise
line usually have a lower GT than other cruise ships. Examples of luxury cruise lines are Crystal
Cruise Lines, Seabourn Cruise Line, and Silversea Cruises.
GT
5
Chapter 3 – Physical Estimation and Performance Techniques
Summary
The main purpose of Chapter 3 is to provide techniques for estimating the physical
characteristics and performance of a yacht at the initial design stage. This includes the
dimensions, power requirements, personnel, and others of the yacht design. The techniques in
this chapter are then used in the CSAT to evaluate the implications of the selection of certain
design features in the initial design stage on the profitability potential of the yacht.
Motor Yacht Data
Many of the techniques used to estimate the physical characteristics and performance of
yacht designs in the CSAT are based on statistical data of built yachts. The built yachts analyzed
are listed in Table 1 and are referred to as master yachts in this thesis. The list consists of 21
different class yachts from 12 cruise lines built between 1996 and 2014. These ships varied in
GT between 30,277-225,282 and had electric engines. The table lists the GT, passenger carrying
capacity in double occupancy (NPassengers), overall length (LOA), length between
perpendiculars (LPP), beams in the waterline (BWL), and draft (T) of each ship. By using a
large variation of GT among different class yachts of various cruise lines that have varying
luxury standards and attributes, more accurate predictive methods are created to estimate the
physical characteristics and performance of yacht designs. Note that cruises in the same class are
not analyzed due to data filtering issues.
6
Table 1
Technical Details of Aircraft Carrier
Aircraft
Carrier
Cruise
Lines GT NPassen
ger
LOU
DSPE
AKER
(m)
LPP
(m)
BWL
(m)
T
(m)
AIDAaura AIDA 42,289 1,266 202.8 182.0 28.1 6.19
AIDAluna AIDA 69,203 2,050 252.0 226.0 32.2 7.30
Azamara Journey Azamara 30,277 710 180.4 157.9 25.6 6.05
Taxation Carnival 101,353 2,642 272.2 230.0 35.5 8.23
Mimpi karnaval Carnival 128,251 3,646 305.6 269.2 37.2 8.20
Carnival Wonders Carnival 85,942 2,124 292.5 262.7 32.2 7.90
Carnival splendor Carnival 113,323 3,006 290.2 247.7 35.4 8.30
Celebrity Solstice Star 121,878 2,852 317.2 293.6 36.8 8.30
Costa Luminosa Coast 92,600 2,260 294.0 265.4 32.3 8.00
Impian Disney Disney 128,000 2,500 339.5 303.0 37.0 7.90
New Amsterdam THING 86,273 2,106 285.3 254.0 32.3 7.80
MSC Magnifica MSC 93,330 2,518 292.9 269.1 32.2 7.85
MSC Opera MSC 59,058 1,712 251.2 222.3 28.8 6.81
Norwegian Partition NCL 145,645 3,969 324.0 300.1 39.7 8.30
Epic Norway NCL 155,873 4,228 330.0 288.8 40.6 8.70
American pride NCL 80,439 2,186 280.6 257.6 32.2 7.99
Royal Princess Powers 141,000 3,600 330.0 306.0 37.5 8.53
Princess Ruby Powers 113,561 3,070 289.6 245.0 36.0 8.50
Freedom of the Seas RCI 154,407 3,634 338.8 303.2 38.6 8.50
Oasis Loud RCI 225,282 5,412 361.6 330.0 47.0 9.10
Seabourn Quest Seabourn 32,346 450 198.2 169.2 25.6 6.40
Note. The cruise lines, GT, NPassengers, LOA, LPP, BWL, and T of the parent yacht are listed in the table.
Cabin Luxury Factor
The concept of cabin luxury factor (SLF) is used in this thesis to estimate the GT of
early yacht designs.
The GT of a yacht can be estimated by connecting GT with the sum of all passenger cabin
volumes (VSt). This concept is known as SLF. A cabin with more luxury is considered one of the
larger volumes and more amenities than a cabin with less luxury.
Consider two yachts with the same NPassengers; however, different levels of
luxury based on their respective cabin arrangements. That is, one ship is mostly made up of
cabins with lower luxury while the other is from more luxurious cabins. The volume of the crew
and enclosed public spaces will most likely not differ drastically between the two ships due to
the constant NPassenger; however, the VSt can be much higher for more luxurious ships.
Therefore, the difference in volume between these two ships is mainly due to the VSt difference.
Since GT describes the volume of all enclosed spaces that a ship has, VSt can be used to
estimate GT.
7
To determine the relationship between VSt and GT, the VSt of 14 of the 21 motor
yachts listed in Table 1 is determined. This is achieved by first determining the total floor area
(ASt) of all passenger cabins. When calculating this summation, the size of each cabin type (i.e.
"luxury") is taken into account. Then, assuming the height from floor to ceiling is
2.8 m for all passenger cabins, VSt is estimated for this aircraft carrier. The results of this
analysis are shown in Table 2.
Table 2
ASt and VSt for the passenger cabin of the mother ship
Aircraft Carrier ASt (m2)VSt (m3)
Azamara Journey 7,519 21,053
Mimpi karnaval 34,935 97,818
Carnival Wonders 21,534 60,295
Carnival splendor 28,405 79,534
Celebrity Solstice 26,992 75,577
Impian Disney 30,230 84,644
New Amsterdam 24,326 68,113
MSC Magnifica 22,236 62,261
MSC Opera 12,143 34,000
Norwegian Partition 36,519 102,253
Epic Norway 39,080 109,424
American pride 16,211 45,391
Oasis Loud 60,930 170,604
Seabourn Quest 8,397 23,512
Note. It is assumed that VSt = 2.8 ∗ ASt.
The VSt values for the 14 parent yachts listed in Table 2 are plotted as a function of the
respective GT values, as shown in Figure 2. As the figure shows, there is a linear relationship
between VSt and GT where the linear match of the data points shows an R2 value of 0.97.
Because of this strong correlation, the following linear-fit equation is used to estimate GT:
GT = 1.406(VSt)(1)
8
250,000
R² = 0.97
200,000
150,000
100,000
50,000
0
0 50,000 100,000 150,000 200,000
VSt (m3)
Figure 2. Correlation between VSt and GT. This was analysed for the 14 motor yachts listed in Table 2.
Equation (1) is used in the CSAT to estimate the GT for the initial yacht design. That is,
the user enters the NPassengers and the desired cabin type. There are three options to
choose from that are differentiated based on their level of luxury. The first option is considered
the least luxurious of the three and is defined as the Lower Luxury Stateroom (LLS). LLS is
characterized by having a smaller volume and fewer facilities than other types of cabins.
Examples are normal-sized interior cabins or normal-sized window cabins. The second option is
considered moderate in terms of luxury and is defined as a Medium Luxury Cabin Room (MLS).
The MLS is characterized by having a medium volume and more amenities than the LLS, but
less of the more luxurious cabin type. An example is a normal-sized balcony cabin. The latter
option is characterized as the most luxurious of the three and is defined as the Higher Luxury
Stateroom (HLS). HLS is characterized as having the largest volume and the most facilities of
the three options.
An example of this is a balcony suite. MLS or HLS is considered to have a balcony attached to it
while LLS does not. The cabin types and floor area respectively and the volumes analyzed in this
thesis (and CSAT) are listed in Table 3. These values are based on averages obtained among the
14 parent yachts analyzed for ASt and VSt (see Table 2).
Table 3
Floor area and volume of each cabin type
Cabin type Floor area (m2) Volume (m3)
LLS 14.50 40.60
MLS 23.50 65.80
HLS 39.95 111.86
Note. This type of cabin and the floor area and volume respectively are used in the CSAT.
GT
9
Volume Displacement
The displacement volume ( ) of each aircraft carrier is estimated through the following ∇
equation in m³:
∇= CB, PP(LWLBWLT)(2)
In equation (2), LWL, BWL, and T are known for each parent yacht through Table 1. Thus,
the only thing that is not known in the equation is the block coefficient based on LPP
(CB,PP). CB,PP can be estimated using Alexander's formula (van Lammeren, et al, 1948) as
follows:
CB, PP
= 1,08 − 1
0.595
(
vTrial
)(3)
√g∗LPP
vTrial in equation (3) is the experimental speed of the ship in m/s. g is the acceleration
of gravity with a value of 9.81 m/s². The estimated CB,PP for each mother yacht is shown in
Table 32 in Appendix A.
∇ can now be estimated through equation (2) for each parent yacht, as shown in Table 32
in Appendix A. Correlation between GT and ∇ for the mother yacht is plotted in Figure
3. The power match of the data point shows an R2 value of 0.98. Because of this strong correlation,
this match equation is used to estimate ∇ in m3:
∇ = 1.365(GT)0.912 (4)
120,000
R² = 0.98
100,000
80,000
60,000
40,000
20,000
0
0 50,000 100,000 150,000 200,000 250,000
GT
∇
(m3)
10
Figure 3. Correlation between ∇ and GT. This correlation is shown among the mother yachts.
11
Displacement Weight
Since the yacht is lifted by float, by balancing the weight of the ship with the buoyancy
force, the displacement weight (∆) of the yacht design can be estimated by the following
equation using ∇ solved through equation (4):
ρswg∇ = ∆g → ∆ =
ρsw∇ (5)
ρsw in equation (5) is the density of saltwater which has a value of 1025 kgm−3 at
15ºC. Dividing this equation by 1,000 gives the weight of the ship in metric tons. Refer to Table
32 in Appendix A for an estimate of the ∆ of the mother yacht.
Beam Dimensions, Length, Draft, and Hull Depth
Beam
The correlation between BWL and GT exists between the mother yachts, as shown in
Figure 4. The data point power match shows an R2 value of 0.95. Thus, this match equation is
used to estimate BWL as follows:
BWL = 1.304(GT)0.285 (6)
One of the interesting features of Figure 4 that is noteworthy is a group of data points
that correspond to yachts with various GTs that have BWL values just under 32.3 m, as
circled in the image. This is likely due to the limitations of the Panama Canal, which requires
ships to have a BWL of less than 32.3 m in order to pass through the canal lock.
50 R² = 0.95
45
40
35
30
25
20
15
10
5
0
0 50,000 100,000 150,000 200,000 250,000
GT
Figure 4. Correlation between BWL and GT. This correlation is shown among the mother yachts.
BWL
(m)
12
Length
The correlation between LOA and ∇1/3 is evident among the mother yachts, as shown
in Figure 5. The linear match of the data points shows an R2 value of 0.96. Thus, the
following matching equation is used to estimate the LOA of a yacht design in m:
SPEAKERS = 7,904(∇)1/3 (7)
400
350
R² = 0.96
300
250
200
150
100
50
0
0 10 20 30 40 50
∇1/3
(m)
Figure 5. Correlation between LOA and ∇1/3. This correlation is shown among the mother yachts.
A strong correlation between LPP and LOA among the mother yacht is shown, as
shown in Figure 6. The linear match of the data points shows an R2 value of 0.97. Using the
LOA estimate through equation (7), the LPP can be estimated through the following equation
of this match in units m:
LPP = 0.894(LOUDSPEAKER)(8)
Speaker
(m)
13
350
300
R² = 0.97
250
200
150
100
50
0
0 100 200 300 400
Speaker (m)
Figure 6. Correlation between LPP and LOA. This correlation is shown among the mother yachts.
With regard to the length in the waterline (LWL) of the yacht design, it is assumed that the
LWL is 102%
from LPP.
Bagan
Since LWL, BWL, CB, PP, and ∇ can now be estimated through the previous
relationship, T can be estimated in units of m by rearranging equation (2) as follows:
∇=
CB,PP
(L
WL
B
WL
T)→ T = ∇
CB, PP
(LWLBWL)
(9)
Stomach Depth
The correlation between LOA and D between the mother yacht is shown, as shown in
Figure 7. The power match of the data points in the image shows an R2 value of 0.90. This
matching equation is followed to estimate D in m:
D = 0.26(LOUDSPEAKER )0.782 (10)
LPP
(m)
14
30
R² = 0.90
25
20
15
10
5
0
0 100 200 300 400
Speaker (m)
Figure 7. Correlation between D and LOA. This correlation is shown among the mother yachts.
Volume
The total volume in m3 of all enclosed spaces on a yacht (VTot) can be attributed to GT
by the following summation:
GT = K ∗ VTotWith: K = 0,2 + 0,02 ∗ log10(VTot) (11)
VTot is estimated for yacht design by rearranging and approaching equation (11) as
follows:
VTot ≈ 3.17(GT) (12)
The volume of the hull of a yacht design (VH) in m3 can be estimated using the
following equation provided in the Maritime Engineering Reference Book (Molland, 2008):
V = C
′
(L
BD)With: C
′
=
C
+ (1 − C
)
0.8D−
T
(13)
HBOA WL BB B ( 3T )
D (m)
15
Since VTot and VH can now be estimated through equations (12) and (13), the
superstructure volume (VSS) of a yacht design can be estimated in m3 by rearranging the following
equation:
VTot = VH + VSS → VSS =
VTot − VH (14)
Resistance and
Strength
Resistansi
To estimate the amount of power required for the propulsion of a yacht design, the total
ship resistance (RT) is estimated first. RT is mathematically represented by the following
equation:
1
RT =
CT (2
ρsw
v2
S) (15)
In equation (15), CT is the total ship's resistance coefficient, v is the ship's speed, and S
is the ship's wetted surface. In this thesis, S is estimated in m2 using the following formula
provided in the publication Methods of Predicting Power (Holtrop & Mennen, 1982):
S = LWL(2T + B)√ CM[0,453 + 0,4425CB − 0,2862CM (16)
− 0.003467 (B / T) + 0.3696CWP] + 2.38 (ABT / CB)
In equation (16), CM and CWP are the center coefficients of ships and waterplanes,
respectively.
CM and CWP are estimated through the following formulas provided in Ship Resistance and
Propulsion (Hudson, Molland, & Turnock, 2011) and Ship Design and Performance for Masters
and Mates (Barrass, 2004) respectively:
CM = 0,80 + 0,21(CB)(17)
C= 2 (C ) +
1(18)
WP 3B3
The last term in equation (16) is for consideration of the surface of a rounded arc that is
wetted. With respect to this term, ABT is the cross-sectional area of a bulb in front of a
perpendicular. AM is the area of the middle of the ship required to estimate the ABT as
follows:
16
AM =
CM
(B ∗ T) = [0,80 +
0,21(CB
)](B ∗ T) =
ABT
KABIN
(19)
17
As shown by equation (19), the bulb cross-sectional parameter (CABT) needs to be
known to estimate ABT. The CABT value is selected in such a way that the residual power
reduction coefficient (∆CP∇R) is maximized. ∆CP∇R is a measure of the percentage
reduction in power using a bulb compared to a normal arc where a larger value indicates a
greater reduction in power. Kracht (1978) assigns the value ∆CP∇R as a CABT function for
the Froude number range (Fn), as shown in Figure 8. This figure applies to CB equal to 0.7.
Since the average CB among the parent yachts is 0.68, it is assumed this figure also applies to
the yacht designs analyzed in the CSAT as well. The figure shows the largest ∆CP∇R for
all Fn curves approximately at CABT equal to 0.125. Therefore, this value is assumed and
ABT can now be estimated through the rearrangement of the equation (19).
Figure 8. ∆CP∇R as a function of CABT. Reprinted from Ship Resistance and Propulsion (p. 327), by D.A. Hudson,
A.F. Molland, & S.R. Turnock, 2011, New York, NY: Cambridge University Press. Hak Cipta 2011 oleh D.A.
Hudson, A.F. Molland, & S.R. Turnock, 2011.
The equation (16) used to estimate S needs to be corrected (i.e. SCorr) to consider the
type of complement that a yacht design can have. Cruise ship designs can have traditional
propulsion and maneuvering systems or pods in this thesis. The wetted appendage surfaces
associated with traditional propulsion and maneuvering systems (e.g. shafts, steering, etc.) will
differ from pod propulsion and maneuvering systems (e.g. pods). To estimate SCorr for
traditional propulsion and maneuvering systems (SCorr, Trad) and pods (SCorr, Pod), the
following equation is used:
SCorr,Trad = S(1 + 0.0075 ∗ NRudder + 0.03 ∗ NShaft)
(20a)
SCorr,Pod = S + 87.2 ∗ N
Under
(20b)
In equation (20a), NRudder and NShaft are the number of rudders and shafts that a
yacht is designed to have. The values of 0.0075 (0.75%) and 0.03 (3%) represent the percentage
increase that each complement will have on the overall wetted surface of the vessel. For this
equation, it is assumed the yacht design will not have a boss. With respect to equation (20b),
NPod is
18
C =
The number of pods that the ship is designed to have. The value of 87.2 in this equation
represents the approximate wetted surface of each pod in m2. Taking this correction into
account, RT is now defined as follows:
1
RT =
CT (2
ρsw
v2
SCorr) (21)
To estimate the RT, the total ship resistance coefficient is first estimated through the
following equation:
CT = CF + CR + CA + CAA + CAS (22)
In equation (22) CF, CR, CA, CAA, and CAS are the coefficients of friction, residue,
incremental, air, and steering resistance, respectively. The calculations regarding each
component of CT are detailed in the following paragraphs.
The coefficient of friction resistance is estimated using the ITTC 1957 ship-model
correlation line which corresponds to the following equation:
0.075
F(log10
Rn−2)2
(23)
In equation (23), Rn is the Reynolds number (vLWL/υ) where υ is the kinematic
viscosity of salt water (1.188 ∗ 10−6m2/s at 15ºC).
Since the resistance coefficient of the rest of the ship will be equivalent to the model, the
model test data is used to estimate the CR. The model test data provided in the publication
Ship Resistance – Effect of Form and Principal Dimensions (Guldhammer & Harvald, 1974)
was used to estimate CR because the model test data was clearly not available for the yacht
design generated in the CSAT. This empirical method is based on an extensive analysis
consisting of many documented model tests. In this publication, a CR plot plotted as a function
of Fn (between 0.15 and 0.45), a prismatic coefficient (CP), and LWL/∇1/3 is provided.
Each CR diagram applies to a given LWL/∇1/3 between 4.0 and 8.0. Each curve in the
chart applies to a given CP between 0.50 and 0.80. CR diagram relating to LWL/∇1/3
between 6.5 and
8.0 is used in the thesis (see Appendix B) because all parent yachts have LWL/∇1/3 values
in this range. Therefore, it is assumed that any yacht design produced in CSAT will also have
an LWL/∇1/3 value in this range.
The hull model used to predict CR can have different aspects of the hull of a yacht.
Guldhammer and Harvald (1974) recommend that if the hull differs from the hull model in the
following aspects, the CR should be corrected:
19
ΔCR,B/T≠2.5: B/T deviation from 2.5 (CR diagram applies to ships with
beam/draft ratio of 2.5)
ΔCR,LCB: The location of the buoyancy center, LCB (CR diagram according to the ship
with LCB close to the best position)
ΔCR, Hullform: Hull variation (CR diagram is based on ships that have a "standard"
shape [i.e. not a typical U or V shape])
ΔCR, Bulb: Spherical arc (CR diagram is based on a ship that does not have a
spherical bow) Considering this correction, CR is now estimated as follows:
CR, Corrected = C
R, Diagram
+ ΔCR, B/T≠2.5 + ΔCR, LCB + ΔCR,
Bentuk lambung + ΔC
R, Bulb
(24)
CR, The diagram given in equation (24) corresponds to the estimated CR through
the diagram (see Appendix B).
Corrections regarding ΔCR,B/T≠2.5 are applied when the block/draft is not 2.5. These
corrections are considered in the CSAT as follows:
DC B−3
R,B/T≠2,5
= 0,16
(
T
− 2.5) ∗
10
(25)
The correction for ΔCR,B/T≠2.5, equation (25), is limited to B/T ≤ 3 because a value
greater than this means that the correction will dominate the total wave-making resistance.
LCB is the longitudinal position of the buoyancy center and is described as the distance
from this point to the center of the ship. In the CSAT, it is assumed the yacht design has an
LCB near the best position, and thus, ΔCR,LCB is assumed to be zero.
CR diagrams apply to vessels that have a "standard" shape. That is, it is not in a typical
U or V shape. In connection with this, the following corrections are recommended for a given
condition:
If the Front Body is: (26a)
U Extreme:
Extreme V:
ΔCR,
Gastric Shape
= −0.1 ∗
10−3
ΔCR, Gastric shape
= +0.1
∗ 10−3
If After Body is: (26b)
U Extreme:
ΔCR, Gastric shape
= +0.1
20
Extreme V:
∗ 10−3
ΔCR,
Gastric Shape
= −0.1 ∗
10−3
21
Guldhammer and Harvald (1974) note that when estimating the effective strength of an
early ship design, it is usually not necessary to make corrections for ΔCR, Hullform (i.e.
equations [26a] and [26b]). Thus, ΔCR,Hullform is assumed to be zero in this thesis.
The CR diagram is based on a ship that does not have a rounded bow. When a vessel
has a rounded bow, a correction for the ΔCR,Bulb listed in Table 4 is recommended. The
correction value applies to the combination of Fn and CP listed in the table. Note that this table
applies to ABT/AM ≥ 0.10. Some cell boxes in a blank table that indicate data are not
available for this particular combination of Fn and CP.
Table 4
Recommended Correction for ∆CR,Bulb ∙ 103
CP
Fn = 0. 15 0. 18 0. 21 0. 24 0. 27 0. 30 0. 33 0. 36
0. 50 +0.2 0 −0,2 −0,4 −0,4 −0,4
0. 60 +0.2 0 −0,2 −0,3 −0,3
0. 70 +0.2 0 −0,2 −0,3 −0,3
0. 80 +0.1 0 −0,2
Note. This correction applies to ABT/AM ≥ 0.10. Adapted from Resistance and Propulsion of Ships (p. 129), by
Sv. Aa. Harvald, 1983, Malabar, FL: Krieger Publishing Company. Copyright 1983 by John Wiley and Sons, Inc.
Since a yacht design can have a combination of Fn and CP corresponding to one of
the empty cell boxes in Table 4 showing ΔCR, the bulb is unknown, the method proposed by
Kristensen and Lützen (2012) is used to estimate ΔCR, the bulb. This method is an extension
of the method of Guldhammer and Harvald (1974) and considers correction due to the influence
of a spherical bow as a percentage of residual resistance based on a regression analysis of 229
model test values for 21 different ships. In their analysis, the total coefficient of resistance was
estimated for each individual ship using the method of Guldhammer and Harvald (1974) without
any correction with respect to the influence of the circular bow. Then, each value is subtracted
from the total resistance coefficient of each ship determined by the model test (i.e. by the
influence of the spherical bow) to estimate the spherical bow correction. From their analysis, the
following equation is derived to estimate ΔCR, Bulb as a function of Fn and CR, Diagram:
ΔCR, Bohlam
=
(250Fn − 90) CR,
Diagram
100
(27)
The roughness of the surface of the vessel will affect the CT. Therefore, an additional
coefficient of resistance is considered when calculating CT in this thesis. Guldhammer and
Harvald (1974) recommend the use of the CA value as the Δ function listed in Table 5.
22
Table 5
CA as a function of δ
D
CA
1.000 T 0,6 ∗ 10−3
10.000 T 0,4 ∗ 10−3
100.000 T 0
1.000.000 T −0,6 ∗ 10−3
Note. Adapted from Resistance and Propulsion of Ships (p. 130), by Sv. Aa. Harvald, 1983, Malabar, FL: Krieger
Publishing Company. Copyright 1983 by John Wiley and Sons, Inc.
The data relationships in Table 5 can be expressed by the following formula:
CA = [0.5 log(D) − 0,1(trunk(D))2] ∗ 10−3 (28)
With regard to the coefficient of air resistance and steering resistance, CAA and CAS
are assumed to be very small and at the initial design stage are assumed to be included in the
additional coefficient of resistance.
Using the techniques provided in this section to estimate the S and CT coefficients , the
RT can now be estimated for yacht design.
Propulsion Power
The power required to move a ship through the water (or pull a ship at a certain speed)
is defined as effective power (PE). PE is estimated by the following equation that relates the
total ship resistance to velocity:
PE = RT ∗ v (29)
The brake force required to propel the ship (PB,P) is related to the effective power by
the following equation:
P =
ON
=
ON
(30)
B,P
hBhSηM
hTot
In equation (30), ηH, ηB, ηS, and ηM are the hull, propeller, shaft, and mechanical
efficiency of the ship's propulsion system, respectively. ηTot in the equation is the total
efficiency of the ship's propulsion system which is a combination of all the sub-efficiency
components (i.e. ηH, ηB, ηS, and ηM). It is considered unnecessary in this thesis to
estimate each component of sub-efficiency because the propulsion power of the parent yacht
(see Table 1) can be attributed to its effective strength to estimate ηTot. More specifically, all
parent cruises
the ship has an electric engine; However, the main distinguishing feature among master cruises
23
Boats are a type of propulsion and maneuvering system. This means that 12 ships have
traditional propulsion and maneuvering systems (i.e. shaft and rudder) while 9 ships have pod
propulsion and maneuvering systems. Therefore, to estimate ηTot, a ship with the same
propulsion and maneuver system is plotted for PE as a function of PB,P multiplied by ηTot,
as shown in Figure 9. By adjusting each data series linearly, the equation is created in the linear
form y = m x.∗
The slope, m, in this equation is equivalent to ηTot whereas x is PB,P. The ηTot value is 0.516
and
0.578 for traditional and pod propulsion and maneuvering systems. These values are assumed
in this thesis.
35,000
30,000
Traditional Pod (R2 =
0.90) (R2 = 0.94)
25,000
20,000
15,000
10,000
5,000
0
0 10,000 20,000 30,000 40,000 50,000 60,000
PB,P • ηto (kW)
Figure 9. PE as a function of PB, P•ηTot for traditional propulsion and maneuvering systems and pods. This
correlation is shown among the mother yachts.
Estimated Total Power
PB,P is simply the power needed for the propulsion of a yacht. Obviously, there will be
other components of the ship (e.g. for habitability and ship support) that will require power.
Typically, electrical load analysis will be carried out at a later stage of the design to predict the
power required for the various power-consuming components of the vessel. However, as much
is unknown at the initial design stage, PB,P is used to estimate the total braking power of the
ship (PB,Tot) because a strong correlation is shown between these variables among the mother
yachts, as shown in Figure 10. The following equation of the linear fit (R2 = 0.93) of the data
point is used to estimate PB, Tot in kW:
PE
(kW)
24
PB,To = 1.696(P
B,P
)(31)
25
100,000
90,000
80,000
70,000
60,000
50,000
40,000
30,000
20,000
10,000
0
R² = 0.93
0 10,000 20,000 30,000 40,000 50,000 60,000 70,000
PB,P (kW)
Figure 10. PB,Tot as a function of PB,P. This correlation is shown among the mother yachts.
Machine-Based Total Brake Power
The total braking power of the ship estimated through equation (31) represents the
approximate minimum braking force required by the ship's engine to power all the needs of the
boat. The maximum continuous rating (MCR) of a boat engine will likely differ from PB's
estimates, Tot because engine models come in limited quantities of different power outputs.
Nevertheless, the MCR of all ship engines, MCRTot, must equal or exceed PB,Tot to ensure
the ship's power requirements are met. That is
MCRTot ≥ P
B, to
(32)
In this thesis, the type of engine considered is diesel and gas turbine engines. The MCR
of a diesel engine is assumed to be 6,000 kW or 12,600 kW. On the other hand, the MCR of a
gas turbine is assumed to be 4,600 kW or 25,000 kW. MCR engine yacht design in this thesis is
based on its GT as follows:
For Diesel Engine:
Kalau GT < 40,000 →# Diesel Engine =
PB, Until
6,000
kW
Kalau GT ≥ 40,000 →# Diesel Engine =
PB, Until
12,600
kW
(33a)
(33b)
PB, To
(kW)
26
For Gas Turbine Engine:
If GT < 40,000 → # of gas turbine engines =
PB,Tot
4,600
kW
If GT ≥ 40,000 →# gas turbine engine = PB,Tot
25,000
kW
(33c)
(33d)
Most likely, the calculation through the equation (33a-d) will not yield an integer.
Therefore, the output of this equation is rounded to the next integer (e.g. 2.2 → 3). Taking these
considerations into account, the total MCR of the yacht design engine in this thesis is estimated
by the following equation:
MCRTot = (# of machines) ∗ (MCR of each machine) (34)
Manning
International Maritime Organization (IMO) Resolution A.890 (1999) establishes the
principles of safe placement. In this resolution, it is stated that the minimum level of safe
personnel of a ship must be estimated by taking into account all relevant factors which include:
1. Size and type of vessel
2. Number, size, and type of main propulsion units and aids
3. Ship construction and equipment
4. Treatment methods used
5. Cargo to be carried
6. Frequency of port visits, length and nature of the voyage to be carried out
7. Trade, waters, and operations areas in which ships are involved
8. The extent to which training activities are carried out on board
9. Limits on working hours and/or rest requirements that apply
In the early stages of a ship's design, it is often difficult to gauge the exact number of
personnel needed on a ship because the design is incomplete at the time. Nonetheless, the total
number of crew members (NCrew) for each aircraft carrier is known. In addition, since the
mother yachts are in operation, they clearly adhere to the minimum level of safe personnel.
Therefore, using correlations between parent yachts, NCrew can be estimated.
The correlation is shown between the mother yacht between the NCrew and the GT,
as shown in Figure 11. As the image shows, NCrew is linearly comparable to yacht GT. The
linearly mounted data point shows an R2 value of 0.98. Because of this strong correlation,
the following equation of this match is used to estimate NCrew as a GT function:
Total = 0.0107(GT)(35)
27
3,000
R² = 0.98
2,500
2,000
1,500
1,000
500
0
0 50,000 100,000 150,000 200,000 250,000
GT
Figure 11. NCrew as a function of GT. This correlation is shown among the mother yachts.
Vessel Weight Breakdown – Displacement, Light Vessel Weight and Dead Weight
Summary
Although, the displacement of the yacht design has been estimated through equation (5),
it is also feasible to estimate the displacement of the yacht (ΔLSW+DWT) based on the
weight of the light vessel (LSW) and dead weight (DWT) as follows:
ΔLSW+DWT = LSW + DWT (36)
ΔLSW+DWT is estimated in this thesis because the LSW and DWT weight group
estimates are then used to analyze the initial stability.
Light Boat Weight
The LSW of a yacht is mainly composed of structural hull (WH), superstructure
(WSS), interior equipment (WIO), ship equipment (WSO), and engine weight group (WM).
This includes all passenger cabins, public spaces, kitchens (i.e. dining rooms), warehouses,
offices, and all crew rooms (Lamb, 2004). LSW is estimated as follows through the summation
of the components of this weight group:
LSW = WH + WSS + WIO + WSO + WM (37)
NCre
w
28
The weight groups of LSW WH, WSS, WIO, and WSO are estimated in this thesis
through the concise form of the table provided in Ship Design and Construction (Lamb, 2004)
relating to yacht design (i.e. Table 6).
Table 6
LSW Estimation for Cruise Ships
Weight Groups Unit Ton/unit coefficient
Lambung (WH) Stomach Volume 0.080
Superstructure (WSS)Superstructure Volume 0.040
Interior Furnishings
(WIO)
Furnished Areas 0.170
Ship Equipment (WSO)Total Volume 0.007
Engine (WM) Installed Power 0.065
Note. Adapted from Ship Design and Construction (pp. 37-9), by T. Lamb, 2004, Jersey City, NJ: Society of Naval
Architects and Marine Engineers. Copyright 2004 by the Society of Naval Architects and Marine Engineers.
As Table 6 shows, to estimate the WIO, the furnished area (AFurn) of the yacht
design needs to be known. Ship Design and Construction (Lamb, 2004) provides a means to
estimate AFurn by correlating AFurn with GT, as shown in Figure 12. The linear match of
the data points in this image corresponds to the following equation:
Aurn = 0.7375(GT)(38)
Figure 12. AFurn as a function of GT. Adapted from Ship Design and Construction (pp. 37-10), by T. Lamb,
2004, Jersey City, NJ: Society of Naval Architects and Marine Engineers. Copyright 2004 by the Society of Naval
Architects and Marine Engineers.
29
Although, Lamb (2003) provides a relationship to estimate the engine weight group of
the LSW yacht design (see Table 6), this relationship is considered inappropriate because it
only applies to diesel engines (i.e. this thesis considers diesel engines as well as gas turbine
engines). Thus, Watson and Gilfillan's equation (1977) is used to estimate WM instead. This
equation separates the main engine weight (WME) from the remaining engine weight
(WRem) as follows:
WM= ∑ WME + WRem (39)
In this thesis, the WME diesel engine is assumed to be 59 t and 176 t respectively for
the 6,000 kW and 12,600 kW engines. On the other hand, WME is assumed to be 2.8 t and 4.7 t
respectively for 4,600 kW and 25,000 kW gas turbine engines. These values are based on real
machines.
As stated, yacht design is assumed to have an electric engine (i.e. a power plant) in this
thesis because all parent yachts have one. The following equation proposed by Watson and
Gilfillan (1977) is used to estimate WRem for power plant configurations:
WRem = 0.72(MCRTot)0.78 (40)
Dead weight
The DWT groups considered in this thesis are as follows: weight of passengers and crew
and their goods (WP&C), inventory and storage (WP&S), fuel oil (WFO), lubricating oil
(WLO), fresh water (WFW), black water in the holding tank (WBW), gray water in the
holding tank (WGW), and water in the swimming pool (WSP)). The following summation of
these groups provides a means of estimating DWT:
DWT = WP & S + WSP + WP & C + WFO + WLO + WFW +
WBW + WGW (41)
To estimate the WP&S and WSP in this thesis, a compact form of the table provided
in Ship Design and Construction ( Lamb, 2004) relating to yacht design is used (i.e. Table 7).
Table 7
Methods for Estimating WP &S and WSP
Weight Groups Unit Coefficient
ton/unit
Estimated
Weight (T)
Terms and Conditions and Stores
(WP &S)
Orang 0.20
Water in the Pool (WSP)200
Note. Adapted from Ship Design and Construction (pp. 37-9), by T. Lamb, 2004, Jersey City, NJ: Society of Naval
Architects and Marine Engineers. Copyright 2004 by The Society of Naval Architects and Marine Engineers.
30
The WP&S in Table 7 is estimated based on the number of people (i.e. passengers and crew)
on board the cruise ship. The WSP values in this table are applied to each yacht design
analyzed in this thesis.
The WP&C deadweight component takes into account the weight of all passengers
and crew members as well as their personal belongings (e.g. luggage). It is assumed that the
average weight of a person is 100 kg. In addition, it is assumed that the weight of personal
belongings carried on board by passengers is 50 kg and 100 kg for crew members. This
difference in weight is because crew members tend to have more personal belongings because
their stay is longer. With this consideration in mind, the following equation is used to estimate
WP&C in metric tons:
WP & C = (150 ∗ NPassenger) + (200 ∗ NCrew)
(42)
Lamb (2003) does provide a methodology for estimating WFO for yacht design.
However, this only applies to yachts with diesel engines. Thus, this methodology is not used in
this thesis. Instead, the following equation is used to estimate WFO in metric tons:
WRange
FO
=SFR ∗ MCR(
v
∗ CF (43)
Experiment
The SFR in equation (43) is the engine's specific fuel rate. In this thesis, the SFR of
diesel engines is assumed to be 185 g/kWh and 173 g/kWh respectively for 6,000 kW and
12,600 kW engines. On the other hand, the SFR is assumed to be 270 g/kWh and 227 g/kWh for
4,600 kW and 25,000 kW gas turbine engines, respectively. These values are based on real
machines.
The Range variable in the equation is based on the vTrial and the approximate fuel tank size
of the yacht design. The CF in the equation is the same correction factor as 0.90 which explains
the fact that cruise ships rarely require their engines to operate at full MCRTot, except in
extreme circumstances.
The WLO value is provided in Ship Design and Construction (Lamb, 2003) and is 20 t
for diesel engines and 1% of that value for gas turbine engines (i.e. 0.2 t).
Although, modern cruise ships often produce fresh water by evaporating salt water
during the voyage, these cruise ships will also store fresh water in tanks due to unforeseen
circumstances. To estimate the weight of fresh water stored in this tank, the following equation
is used:
WFW = 50 ∗ 3.5 (NPassengers + N
Crew
)(3.785 ∗ 10−3)(44)
With regard to equation (44), the capacity of a freshwater storage tank is based on the
number of gallons used per person per day for a given number of days. One is assumed to be
31
using 50 gallons per day and a freshwater storage tank is assumed to hold up to a cumulative 3.5
32
period of day people need. The value of 3.785 ∗ 10−3 in the equation is required to convert
the Imperial gallon unit to the Cubic meter Metric unit. Note that the unit of output of this
equation denotes the unit of volume rather than mass; however, since WFW is represented in
metric tons and freshwater density is assumed to be 1,000 kg/m3, the two are identical.
Black water consists of wastewater that is mostly produced from toilets (i.e. sewage).
Nowadays, cruise ships are allowed to release their black water when they are at least a certain
distance from the shore. However, if this is not the case (e.g. when the ship is in port), the ship
must be able to store its black water. WBW is estimated in this thesis based on the number of
people on the cruise ship and the amount of black water each person produces. According to the
Ocean Conservancy (2002), the average person produces 5-10 gallons of black water per day. In
addition, the cruise ship can accommodate up to three cumulative days of this production. Based
on this idea, WBW is estimated for the yacht design as follows:
WBW = (NPassengers + NCrew) ∗ (10 ∗ 0.003785) ∗ 3 ∗ 1.025
∗ Margin (45)
With regard to equation (45), it is assumed the average person on a cruise ship produces
10 gallons of black water per day and the ship's black water tank has the capacity to hold up to 3
cumulative days of production. The value of 1.025 in this equation takes into account the density
of black water and the conversion to metric ton units for WBW. A margin of 10% (i.e. a margin
equal to 1.1) is added to the estimate to be conservative.
Grey water consists of non-waste wastewater from dishwashers, showers, laundry,
kitchens, and others. According to the Ocean Conservancy (2002), the average person on a
cruise ship produces 30-85 gallons of gray water per day. In addition, the cruise ship can
accommodate up to three cumulative days of this production. Based on this idea, the following
equation is used to estimate the WGW for yacht design:
WGW = (NPassengers + NCrew) ∗ (40 ∗ 0.003785) ∗ 3 ∗ 1.025
∗ Margin (46)
With regard to equation (46), it is assumed the average person on a cruise ship produces
40 gallons of grey water per day and the ship's grey water tank has the capacity to hold up to 3
cumulative days of production. The value of 1.025 in this equation takes into account the density
of gray water and the conversion to metric tons for WGW. Again, a 10% margin is added to the
forecast to be conservative.
Note
Note that this thesis presents two methods for calculating ∆. One method is through the
correlation between the mother yacht (i.e. equation [5]) and the other is by adding LSW to the
DWT (i.e. equation [36]). Nonetheless, this is not a problem because the difference in ∆
33
values estimated through the two methods is small. Again, note that the LSW and DWT weight
groups are expected to analyze the initial stability.
34
W
L
Initial Stability
Estimation Techniques
Stability is an important aspect to consider in the initial design of a ship because an
unstable ship will obviously not be a viable design even if it is considered potentially profitable.
Although, profitability is the focus of this thesis, it is considered beneficial to analyze stability in
some ways.
The initial stability of the yacht design is analyzed in this thesis. Initial stability is when
a ship is upright, or very close (i.e. a very small angle of inclination). Vertical buoyancy center
(KB), transverse and longitudinal metacenter (KMT,L), transverse and longitudinal
metacentric radius (BMT,L), center of gravity (KG), and transverse and longitudinal
metacentric altitude (GMT,L) are estimated for the yacht design. This vertical distance refers
to the distance from the yacht's baseline.
KB is the point at which the buoyancy force acting on the hull of the ship works. Using
the formula provided in Ship Design for Efficiency & Economics (Schneekluth & Bertram,
1998), KB is estimated in meters as follows:
KB = T(0,9 − 0,3 ∗ CM − 0,1CB)(47)
BMT, L is the vertical distance between KB and KML, T respectively. For ship-
shaped ships, BMT,L can be estimated as follows:
BMT =
ηT∗B
2
T∗C
B
l∗L2
With: ηT = 0,084 ∗ (CWP)2 (48a)
3
BML =
PP
T∗C
B
With: hL
=
∗ (C)2 (48b)
40
ηT,L in equations (48a) and (48b) is the coefficient estimated through the previous
formula provided in Ship Design and Performance for Masters and Mates (Barrass, 2004).
This formula ηT,L applies to CWP values between 0.692 and 0.893.
KMT,L is the distance from the keel to the GMT,L respectively. The following
equation is used to estimate KMT,L:
KMT = KB + BMT (49a)
KML = KB + BML (49b)
35
D
V S
KG is the point at which all the weight of the ship acts. The KG of a yacht at full load is
estimated in this thesis using the weight group estimation technique discussed earlier and estimating
the vertical center of gravity (VCG) of each weight group. It is mathematically as follows:
KG =
1
LSW +
DWT
(W
H
∗
VCG
H
+
WSS
∗
VCGS
S
+
WH
ERE
∗
VCG
O
+
WM
∗
VCG
M
(50)
+ WP&S ∗ VCGP&S + WSP ∗ VCGSP + WP&C ∗ VCGP&C +
WTanks ∗
VCG Tanks
)
With regard to equation (50), WTanks is the sum of the weight of the fully filled tank
of the yacht design, as mathematically represented by equation (51). WO is the sum of the
interior weights and fittings of the yacht design, as mathematically represented through
equations (52). It is assumed that the VCG of each component in its respective group, occurs at
the same height.
WTanks = W
FO
+ WLO + WFW + WBW + WGW (51)
WO = WIO + WSO (52)
The VCG of the hull structure of a yacht (VCGH) is based on the following formula
provided by Kupras (1971):
VCG
H
L
= 0,01D [46,6 + 0,135(0,81 −
CB) ( ) ] L < 120 m (53a)
VC
G
D
= 0,01D [46,6 + 0,135(0,81 − C)
L LL ≥ 120 m (53b)
H B
( )
] + 0.008D
(
B
− 6.5)
The units of equation (53a) and (53b) in meters and L are related to LWL.
VCG of the yacht superstructure material (VCGSS) is assumed to be located 40%
of the distance from the main deck surface to the ceiling surface of the uppermost level of the
superstructure. This is because the superstructure is assumed to have a rectangular prism shape
from the rearmost edge of the superstructure to the longitudinal point where the ship's pilot
space begins. From this point forward, the superstructure is assumed to be tilted to allow for
more favorable air resistance characteristics. Thus, the VCGSS is estimated in meters as
follows:
VCGSS
= D + 0.4 ( ) (54)
LPP∗B
2
2
36
The VCG of yacht equipment (VCGO) is usually located above the main deck. To
estimate the VCGO in meters, the following equation proposed by Kupras (1971) is used:
37
VCGO = D + 1.25 L ≤ 125 m (55a)
VCGO = D + 1.25 + 0.01(L −
125)
125 m < L ≤ 250 m (55b)
VCGO = D + 2.50 250 m < L(55c)
The unit of equation is derived (55a-c) in meters and L in LWL.
VCG yacht engines (VCGM) depend on the inside height (hdb) and the overhead
height of the engine room (D′). Kupras (1971) suggested the following formula for estimating
VCGM in meters:
VCGM = hdb + 0.35(D
′
− hdb)(56)
The value of 0.35 in equation (56) is in relation to the VCGM which is assumed to be at
35% of the height inside the engine room space. For the shipping design analyzed in this thesis,
the engine room is assumed to be two decks high because the engines that the ship is most likely
to have inside this space are. Also, the height of the deck is assumed to be 2.8 m. Taking these
considerations into account, D′ is estimated as follows:
D
′
= 5.6 + hdb (57)
With regard to the hdb variable in equations (56) and (57), according to the
classification of ABS, the minimum value of hdb should be as follows:
hdb ≥ 32 ∗ B + 190√T (58)
The unit of equation (58) is millimeters. To be wise, a 10% margin is added to the
hdb on CSAT.
The VCG of yacht inventory and storage (VCGP&S) is assumed to be located at the
deck level where they will be loaded. That is, the first deck that is actually above the water
surface. The vertical location of the VCGP&S within the deck is assumed to be at 40%
distance from the deck surface to the ceiling surface. Assuming this deck is 2.8 m tall and the
deck surface is 1 m above water level, VCGP&S estimates as follows:
VCGP&S = T + 2,12 (59)
The yacht's swimming pool is assumed to be located on the superstructure level just
below the topmost level. Assuming the pool has a depth of 1.5 m, the VCG with respect to the
pool water weight (VCGPS) is estimated as follows:
38
VCGSP
= D + VSS − 3,55 (60)
LPP∗B
In order to estimate the VCG regarding the weight of passengers and crew and their
personal belongings (VCGP&C), various assumptions are made. It is assumed that the weight
regarding passengers and their personal belongings (WPassengers) is evenly distributed
throughout the level of the ship's superstructure. Thus, the VCG of this weight is assumed to be
at 50% of the distance from the main deck surface to the ceiling surface of the uppermost level
of the superstructure. With regard to the weight of crew members and their personal belongings
(WCrew), it is assumed that this weight is evenly distributed across the deck of the ship. Thus,
the VCG of this weight is assumed to be at 50% of the distance from the vertical position of
hdb to the ceiling of the uppermost superstructure level. Taking these considerations into
account, VCGP&C is estimated to be as follows:
VC
G
=
1
{W (D +
0,5∗VSS
)
+ W [h + 0.5 (D +
VSS
− jam )]} (61)
P & C
WP & C
Pass
eng
er
LPP∗
B
Awa
k Db
LPP∗ B Db
It is assumed all cruise ship tanks consist of the hull volume between the ship's baseline
and the lower inner height. In addition, it is assumed that the VCG of all ship tanks
(VCGTanks) is positioned at 50% of this vertical distance. Thus, VCGTanks is estimated as
follows:
VCGTanks = 0,5 ∗ hdb (62)
By incorporating the VCG and W values of the LSW and DWT groups respectively into
equation (50), the design of the KG ship can be estimated. Then, GMT,L can be estimated as
follows due to the distance between KG and KMT,L:
GMT = KMT − KG (63a)
GML = KML − KG (63b)
Stability Criteria
At small angles of inclination (i.e. <3º), for certain positions KG and KM that are
considered fixed, GM will be constant for a given waterline. Since KG can vary with ship
loading, even for a given displacement, BM will be constant for a given waterline (Tupper,
2004). Taking these considerations into account, the following criteria act as a general rule with
respect to the initial stability of the vessel:
1. If the KM is above
KG,
GM and GZ positive →Kandang
2. If KM is in KG, GM and GZ zero →Neutral
39
3. If the KM is below
KG,
GM and GZ negative →Stable
40
Note that the GZ variable listed in the preceding criteria is known as the right lever (or
just the lever) which is estimated as follows for small tilt angles:
GZ = Dosa GM(F)(64)
φ in equation (64) are some small angles of inclination.
IMO Resolution A.749 (1993) is a code on intact stability for all types of ships covered
by IMO instruments. In this resolution, it is stated that the initial metacentric height must not be
less than 0.15 m for passenger and cargo ships. This is the threshold at which the design of the
yacht analyzed in this thesis is considered stable.
41
Chapter 4 – Net Present Value Model
Summary
In this thesis, the NPV model is used to analyze the implications of the selection of certain
design features at the initial design stage on the profitability potential of the yacht.
NPV is the present value of projected cash flows that include investments (Lamb, 2003).
The specific form of the NPV model used in this thesis has the following components:
estimated construction cost (CC), total ship operating cost (CTO), total ship revenue
(BTotal), rate of return (r), and time period (t). The mathematical relationship for estimating
the NPV of a yacht design is as follows:
NPV =
CC
N
t=
1
(BTotal−C
TO)
(1+r)t
where: t = 1, 2,..., N (65)
N in equation (65) is the expected operating life of the vessel. If the NPV value for the
yacht design is positive, the yacht is considered a profitable investment if implemented. On the
other hand, a negative value indicates that the investment will not be profitable. The higher the
NPV, the more favorable the yacht design.
Return Rate and Vessel Operating Life
The specific rate of return (i.e. r) used in equation (65) is the minimum acceptable rate of
return (also known as the hurdle level) that a cruise company will accept before implementing
the initial yacht design. This is assumed to be 10% because S&P 500 companies typically
generate returns between 8% and 11% annually (Wikipedians, n.d.). Note that Carnival
Corporation & plc is on the S&P 500 list. Thus, if the NPV value of the yacht design in this
thesis is positive at the 10% hurdle level, this yacht design is likely to be a successful investment
if implemented.
A vessel operating period (i.e. N) of 30 years was assigned to the yacht design analyzed
in this thesis. This estimate is based on the Royal Caribbean Cruises Ltd. Annual Report 2013
(Royal Caribbean Cruises Ltd., 2013) which determines cruise ships typically have a useful life
of 30 years. Their assessment considers the impact of anticipated technological changes, long-
term cruise and holiday market conditions, and the historical useful life of similarly built
vessels.
+
∑
42
Total Construction Cost
Estimation Techniques
Often, when preparing a bid for a proposed ship, the shipyard will estimate the
construction cost of the ship based on the weight of its various components (e.g. hull, interior
fittings, etc.). However, this cost estimation approach requires ownership data. Therefore, it
would be very difficult to estimate the construction cost in this thesis using this approach
because the data is not available. Also, since the yacht design analyzed in this thesis is
considered to be in the initial design stage, it is an incomplete definition of design. Thus, a
detailed estimate of construction costs is not feasible. Nevertheless, a fairly accurate estimate of
the construction cost for a yacht design can be derived based on two features that determine the
design that have a major influence on its construction cost. These features are the GT of the ship
and the MCR engine. In this regard, the following multi-linear equation relating to GT and
MCRTot with CC is used in this thesis to estimate the cost of yacht construction in $M:
CC = α1(GT) + α2(MCRTot) (66)
To estimate the coefficients α1 and α2 in equation (66), a multi-linear regression of
the response in CC on the GT and MCRTot predictors between the parent yacht data was
performed. Based on this analysis, values of 4.563 and 3.036 were assigned to α1 and α2,
respectively.
Estimation Accuracy Techniques
The accuracy of the construction cost estimation method (i.e. equation [66]) is
evaluated by comparing the CC (note that CC is the estimated construction cost) with the
actual construction cost (CCC, Actual) of each parent yacht, as shown in Table 8. The last
column of this table
shows a percent error (%) when comparing CC to CC, Actual for each parent yacht. Note
that in this analysis the actual GT and MCRTot of each parent yacht are used.
43
Table 8
Comparison of Aircraft Carrier, Actual and CC Yacht CC
Aircraft Carrier CC, Actual ($M) CC ($M) % Error
AIDAaura 445 275 38.04
AIDAluna 425 425 0.01
Azamara Journey 204 195 4.60
Taxation 614 655 6.73
Mimpi karnaval 808 815 0.87
Carnival Wonders 465 582 25.06
Carnival splendor 788 709 9.93
Celebrity Solstice 818 760 7.01
Costa Luminosa 579 617 6.57
Impian Disney 935 817 12.59
New Amsterdam 607 588 3.09
MSC Magnifica 586 602 2.66
MSC Opera 330 362 9.87
Norwegian Partition 840 854 1.67
American pride 540 520 3.69
Royal Princess 735 833 13.31
Princess Ruby 621 722 16.24
Freedom of the Seas 928 934 0.66
Oasis Loud 1,354 1,323 2.31
Seabourn Quest 260 218 16.33
Average Error % 9.06%
Note. The last column of the table is the percentage error between the CC, Actual and CC of each parent yacht.
Also, every fee in the table is given in US dollars in 2014.
As Table 8 shows, the average percentage of errors among the parent yacht is about 9%.
Note that the CC,Actual for each parent yacht is adjusted for inflation in US dollars in 2014.
The inflation rate for each year between 1996 and 2013, as determined by the United States
Department of Labor (2014), is listed in Table 33 in the Appendix
C. Also, note that the CC,Actual for each parent yacht is based on the construction costs
determined by the yacht company, shipyard, and/or other specific sources where these values
may be rounded up and/or generalized by each source. Nevertheless, these values are
considered reasonable to the extent that they provide an estimate of the CC "ballpark" in this
thesis.
Figure 13 shows the correlation between CC, Actual and CC for the mother yacht. The
linear fit equation of the data point has a slope approximately equal to 1 (i.e. 0.99) and an R2
value of 0.93 which shows: a) CC is a linear function of GT and MCRTot and b) CC of each
parent yacht is approximately equal to CC, Actual of that vessel. Therefore, the equation
(66) is considered a reasonable way to estimate the CC for the yacht design analyzed in this
thesis.
44
1,400
R² = 0.93
1,200
1,000
800
600
400
200
0
0 200 400 600 800 1,000 1,200 1,400
CC, Actual ($M)
Figure 13. CC is plotted against CC, Actual for each parent yacht. The linear-fit slope is approximately 1.
Total Operating Costs
Summary
The total operating costs of a cruise can be broken down into the following components:
commission, transportation and other (CCTO); onboard and other (CO&O); fuel (CFuel);
payroll and related (CP&R); food (CFood); and other ship operating costs (COSO).
The sum of these components gives the CTO for the yacht design as follows:
CTO = CCTO + CO & O + CBahan
burn
+ CP & R + C
Food
+
COSO (67)
The specific techniques used to estimate each component of the operating costs in
equation (67) are discussed in the following sub-sections.
Commissions, Transportation, and Other Fees
Commissions, transportation, and other expenses comprise costs that are directly
related to passenger ticket revenue. These include travel agency commissions, air and other
transportation costs, port fees that vary with the number of passengers, and associated credit
card rates (Royal Caribbean Cruises Ltd., 2012). Thus, the CCTO estimate in this thesis is
based on the number of passengers on board the cruise ship during the voyage.
CC ($M)
45
To estimate how the CCTO varies with NPassengers, Norwegian Cruise Line's
Annual Report 2010-2013 (Norwegian Cruise Line, 2010-2013) and Royal Caribbean Cruises
Ltd. Annual Report 2010-2013 (Royal Caribbean Cruises Ltd., 2010-2013) were evaluated. The
annual report of each company for a particular year, detailing the company's activities and
financial performance for that year. In addition, these annual reports are required periodically
(quarterly in this case) by the stock exchanges involved with each company (e.g. the New York
Stock Exchange). In this report, the annual values of CCTO (CCTO, Annual) and
NPassengers (NPassengers, Annual) are determined as well as the average voyage
length (TVoyage, Average) of a given year. Using this information, the CCTO per
passenger per day can be estimated by the following equation for each company and year:
CCTO
=
CCTO,A
nnual
(68)
Passengers∙
Day
(NPassen
gers,Year
)(TVoyage,Letters)
When putting the data into equation (68), it is assumed that all the yachts of any
shipping company operating during a given year are operating every day of the year. Once the
CCTO value per passenger per day is obtained through this equation, each value is adjusted
back to inflation in US dollars in 2014. The results of this analysis are shown in Table 9.
Table 9
CCTO per Passenger per Day
Shipping Companies
Year
Norwegian Cruise Lines
$
( )
passengers/day
Royal Caribbean Cruises Ltd.
$
( )
passengers/day
2010 42.48 39.00
2011 41.76 38.82
2012 40.53 37.36
2013 39.98 36.97
Tengah 41.19 38.04
Average Among
Companies $39.61 per passenger per day
Note. These values are based on the Norwegian Cruise Line Annual Report 2010-2013 (Norwegian Cruise Line,
2010-2013) and the Royal Caribbean Cruises Ltd. Annual Report 2010-2013 (Royal Caribbean Cruises Ltd., 2010-
2013).
The average value of CCTO per passenger per day between the two cruise lines (see the
last row of Table 9) is used to estimate the CCTO per cruise (CCTO, Voyage) and annual
(CCTO, Annual) for yacht design in this thesis as follows:
C = CCTO = [39.61 ∗
(N )] ∗
T(69a)
CTO,
Shipping Trip Passenge
r
Trip
C = CCTO = [39.61
∗ (N
)] (
365
)(69b)
46
CTO, Tahunan Yea
r
Passenge
r
TVoyage
47
Onboard Fees and Other Fees
Onboard and other costs consist of direct costs related to onboard revenue and others.
This includes the cost of products sold on board the yacht, vacation protection insurance
premiums, costs associated with pre- and post-cruise tours, and associated credit card fees as
well as minimal fees associated with concession revenues (Royal Caribbean Cruises Ltd., 2012).
As with the CCTO, the CO&O value depends on the number of passengers for the cruise ship.
Therefore, the CO&O estimate in this thesis is based on the number of passengers on board
the cruise ship during the voyage.
Again, using the Norwegian Cruise Line Annual Report 2010-2013 (Norwegian Cruise
Line, 2010-2013) and the Royal Caribbean Cruises Ltd. Annual Report 2010-2013 (Royal
Caribbean Cruises Ltd., 2010-2013), the annual value of CO &O (CO&O, Annual) is given to
the respective company and year. Using this information, CO&O per passenger per day is
estimated by the following equation for each company and year:
CO&O
=
CO&
O, Annual
(70)
Passengers∙
Day
(NPassen
gers, Year
) (TVoyage, Correspondence)
When putting the data into equation (70), it is assumed that all the yachts of any
shipping company operating during a given year are operating every day of the year. Once the
CO&O value per passenger per day is obtained through this equation, each value is adjusted
back for inflation in US dollars in 2014. The results of this analysis are shown in Table 10
Table 10
CO&O per Passenger per Day
Shipping Companies
Year
Norwegian Cruise Lines
$
( )
passengers/day
Royal Caribbean Cruises Ltd.
$
( )
passengers/day
2010 17.14 15.94
2011 17.22 16.00
2012 17.17 15.34
2013 17.15 15.99
Tengah 17.17 15.82
Average among
Company $16.49 per passenger per day
Note. These values are based on the Norwegian Cruise Line Annual Report 2010-2013 (Norwegian Cruise Line, 2010-
2013) and the Royal Caribbean Cruises Ltd. Annual Report 2010-2013 (Royal Caribbean Cruises Ltd., 2010-2013).
The average value of CO&O per passenger per day between the two cruise
companies (see the last row of Table 10) is used to estimate the CO&O per voyage (CO&O,
Voyage) and annual (CO&O, Annual) for the yacht design in this thesis as follows:
48
C = CO&O = [16,49 ∗
(N )] ∗
T(71a)
O & O, the Trip Passenge
r
Trip
C = CO&O = [16,49
∗ (N
)] (
365
)(71b)
O&O,
Annual Yea
r
Passenge
r
TVoyage
Fuel Costs
Fuel costs are the costs incurred with the purchase, delivery, and storage of fuel as well
as the financial impact of fuel exchange agreements (Royal Caribbean Cruises Ltd., 2012). The
factors that affect CFuel are considered to be the distance traveled by the vessel, the average
power used, and the cost per metric ton of fuel (Molland, 2008).
The cost of fuel is considered in terms of the cost of fuel per metric ton consumed. In
this thesis, these costs are based on the historical costs specified in the 2013 Annual Report of
Carnival Corporation & plc (Carnival Corporation & plc, 2013).
The CFuel during the duration of the voyage (CFuel, Voyage) is estimated in this thesis
by first estimating the power consumption of ships at sea (PSea) and ports (PPort) respectively.
To
estimating PSea, PB,Tot (via equation [31]) and PB,P (via equation [30]) parameters on the
service and
The speed of the experiment is used. It is assumed that when a cruise ship operates at sea, it
travels at the speed of its service. Thus, the PSea for yacht design is estimated as follows in
kW:
PSea = (P
B,P
)
@ vserviwe
+
[
⏟P
_
B
,
_
T
_
ot
_
−
(
_
PB
_,
P
_
)
_
@
_vTria
l
]
MORE
(72)
The second term in the equation (72) is the force dedicated to all other ship systems
(POther). The POther is assumed to remain constant at all ship speeds during transit.
Since cruise ships do not use propulsion when docked in port, PB,P is assumed to be
zero during this time period. In addition, since many systems dedicated to marine operations are
not used in ports and many passengers are assumed to be on land, the power consumption of
cruise ships in ports is assumed to be 85% of POther. Therefore, PPort is estimated in kW
units as follows:
PPort = 0.85 ∗ P
Other
(73)
49
For a given TVoyage and the number of ports that the cruise will visit during the
cruise (NPorts), the duration at sea (TSea) can be estimated. Note that the average length of
time a cruise ship spends in port is assumed to be 6 hours. Using the output through equations
(72) and (73), CFuel, Voyage can now be estimated through the following equation:
50
C = 676 ∗ SFR
[P (24 ∗
T− 6
North
∗) +
P(6
Nort
h ∗
)](74)
Fuel,
Cruise
100
0
Sea
⏟
Voya
_
ge
Test
Port
s
Por
t
Port
In equation (74), the unit of SFR is kg/kW-hour.
Because, CFuel per year (CFuel, Annual) is required to estimate the CTO of the
year (CTO, Annual), the following equation is used to estimate CFuel, Annual:
CFuel,
Annual
= Grill,
Cruise
( 365
TVoya
ge
)(75)
Payroll and Associated Costs
Payroll and related related costs related to personnel on board (Royal Caribbean
Cruises Ltd., 2012). Therefore, CP&R can be estimated using the relationship involving
it and NCrew.
Again, using Norwegian Cruise Line's Annual Report 2010-2013 (Norwegian Cruise
Line, 2010-2013) and Royal Caribbean Cruises Ltd. Annual Report 2010-2013 (Royal
Caribbean Cruises Ltd., 2010-2013), the annual value of CP &R (CP& R, Annual) for each
company and year is provided. Using this data, CP&R per crew member per day can be
estimated by the following equation for each company and year:
CP & R
= CP&
R, Annual
(76)
(Crew
Member)∙Day
(HOLD,
Armada)
∗365
NCrew, Fleet in equation (76) is the number of crew members of all cruise ships
(i.e. fleet) operating during a given year for each company. Again, as in the case of the equation
(68) and (70), when entering the data into the equation it is assumed that all the yachts of each
shipping company operating during the year are each operating every day of the year. Also,
when factoring CP& R, the annual value into the equation, inflation in U.S. dollars in 2014 is
considered. The results of this analysis are shown in Table 11.
51
Table 11
CP&R per Crew Member per Day
Shipping Companies
Year
Norwegian Cruise Lines
$
( )
Crew members∙day
Royal Caribbean Cruises Ltd.
$
( )
Crew members∙day
2010 65.65 60.46
2011 68.89 61.15
2012 70.00 58.20
2013 68.26 57.99
Tengah 41.19 38.04
Average Among
Companies $63.82 per crew member per day
Note. These values are based on the Norwegian Cruise Line Annual Report 2010-2013 (Norwegian Cruise Line, 2010-
2013) and the Royal Caribbean Cruises Ltd. Annual Report 2010-2013 (Royal Caribbean Cruises Ltd., 2010-2013).
From this analysis, the average value of CP&R per crew member per day between the
two cruise companies (see the last row of Table 11) is used to estimate the CP&R per
voyage (CP& R, Voyage) and annual (CP&R, Annual) for yacht design in this thesis as
follows:
CP&
R, Cruise
= (63.82 ∗ NCrew) ∗ TVoyage (77a)
CP&
R, Annual
= (63.82 ∗ NCrew) ∗ 365 (77b)
Food Costs
Meal expenses are expenses associated with meals for passengers and crew of a certain
duration. Since CFood relies on NPassengers and NCrew, relationships involving these
variables can be used to estimate CFood.
CFood per person will differ between NPassengers and NCrew. Therefore,
CFood is estimated
through the following multi-linear equation with coefficients β1 and β2
corresponding to
NPassengers and NCrew , respectively:
CFood = β
1
(NPassenger) + β2(NCrew)(78)
To estimate the values of β1 and β2 coefficients in equation (78), multi-linear
regression analysis was performed using the CFood values per year (CFood, Annual),
NPassengers, Annual, and NCrew specified in the Norwegian Cruise Line Annual
Report 2010-2013 (Norwegian Cruise Line, 2010-2013) and Royal Caribbean Cruises Ltd.
Annual Report 2010-2013 (Royal Caribbean Cruises Ltd., 2010-2013). From this analysis, β1
and β2 are estimated to be 33.89 and 7,227, respectively. Using equation (78) with the value of
this coefficient and the variable
52
NPassengers in the form of NPassengers, Annual, CFood, Annual for yacht
design can be estimated. To estimate CFood per voyage voyage, (CFood,Voyage) the
following equation is used:
C = b
(N
NCrew∗TVoyage
)(79)
Food,
Cruises 1 Passenger, Cruise) +
b2 (
365
Other Ship Operating Costs
Other ship operating costs consist of operational costs such as repairs and maintenance,
port fees (which do not vary with the number of passengers), ship operational charter costs, and
ship-related insurance and entertainment costs (Royal Caribbean Cruises Ltd., 2012). Since the
GT serves as the basis for the assessment of taxes and fees, it is assumed that the COSO will
vary linearly with the GT.
To estimate the rate at which COSO varies with GT, the annual value of COSO
(COSO, Annual) obtained through the Norwegian Cruise Line Annual Report 2010-2013
(Norwegian Cruise Line, 2010-2013) and Royal Caribbean Cruises Ltd. Annual Report 2010-
2013 (Royal Caribbean Cruises Ltd., 2010-2013) was analyzed. In each report, COSO,
Annual corresponds to the value obtained through all yachts operating during that year for
each company. Therefore, the total GT of all cruise ships (GTTotal) in each fleet of shipping
companies operating during this year needs to be estimated. This is achieved by adding up the
GT of all yachts in a cruise company operating in a given year. Using this information, the
COSO per GT per day for each cruise company can be estimated by the following equation for
the respective year:
C
OSO =
COSO,
Annual
(80)
GT∙Day (GTTotal)∗365
Once the COSO value per GT per day is obtained through equation (80) for cruise
companies, each value is then adjusted back to inflation in US dollars in 2014. The results of
this analysis are shown in Table 12.
Table 12
COSO for GT for the Day
Shipping Companies
Year
Norwegian Cruise Lines
$
( )
GT∙day
Royal Caribbean Cruises Ltd.
$
( )
GT∙day
2010 0.65 0.81
2011 0.64 0.79
2012 0.52 0.79
2013 0.53 0.80
53
Tengah 0.58 0.80
Average Among
Companies $0.69 per GT per hari
54
The average value of COSO per GT per day (see last row of Table 12) is used to estimate
COSO per voyage (COSO,Voyage) and annual (COSO,Annual) for yacht design are as
follows:
C = GIZMO = (0.69 ∗
GT) ∗ T (81a)
OSO,
Shipping Trip
Trip
COSO,
Annual
= GIZMO = (0,69 ∗ GT) ∗ 365 (81b)
Year
By entering the estimated variables in this sub-section and the previous sub-section,
CTO can now be estimated through equations (67).
Total Revenue
Summary
The total revenue (or benefits) generated by cruise ships is mainly made up of passenger
ticket revenue (BTicket) and onboard and other revenue (BO&O). Therefore, BTotal can
be estimated as follows:
BTotal = BTicket + BO&O (82)
The specific techniques used to estimate each component of income in equation (82) are
discussed in the following sub-sections.
Passenger Ticket Revenue
Passenger ticket revenue consists of revenue generated from the sale of passenger tickets.
As discussed in Chapter 3, the yacht designs analyzed in the CSAT can have LLS, MLS, and/or
HLS cabin types. The BTicket per passenger per day of each of these cabin types is based on
research by Cruise Market Watch (2012), as provided in Table 13. Note that these values relate
to 2012 and have been adjusted for inflation in US dollars in 2014. The BTcricket values per
passenger per day given in the table are assumed for the yacht design analyzed in this thesis as
well.
Table 13
BTicket per Passenger per Day for Cabin Type (Cruise Market Watch, 2012)
Cabin type BTicket
LLS $142.29
passengers
day
MLS $198.90
passenger
day
55
HLS $303.96
passengers
day
56
Onboard Revenue and Others
Revenue on board and others consists of revenue generated by the sale of goods and/or
services on board a cruise ship that are not included in passenger ticket prices, cancellation
fees, sales of vacation protection insurance, pre- and post-cruise tours, and air packages (Royal
Caribbean Cruises Ltd., 2012).
BO&O for cruise ships can be influenced by many factors such as the type of cruise
line (e.g. contemporary, premium, or luxury), the age of the passengers, the income of the
passengers, and many other factors. Since the type of shipping line is not measured in this
thesis and because the age of passengers and passenger income are also related to the spending
habits of passengers on board ships and other passengers, the parameter used in this thesis to
estimate BO&O is the average passenger income.
The International Association of Cruise Lines (CLIA) is a cruise industry trade
association with representatives in North and South America, Europe, Asia, and Australasia. In
the Cruise Lines International Association Shipping Market Profile Study 2011 (2011), BO&O
per day is related to passenger revenue, as listed in Table 14. Their analysis is based on a poll of
more than 1,000 cruise ship passengers. Note that in their analysis, passengers who make less
than $40 thousand are not considered. The BO&O values per passenger per day given in the
table are assumed for the yacht design analyzed in this thesis as well.
Table 14
BO &O per Passenger per Day (International Association of Cruise Lines, 2011)
Income MO &O
$40K - $59K $53.12
passengers
day
$60K - $79K 65.13
passengers
day
$80K + 66.13
passengers
day
57
Chapter 5 – Cruise Ship Analysis Tools
To analyze the implications of selecting certain design features in the initial design stage
on the profitability potential of a yacht, the Cruise Ship Analysis Tool is built in Excel. In more
detail, CSAT provides a means to analyze the physical characteristics and performance of the
initial yacht design in a clear, concise, and user-friendly interface. CSAT consists of three Excel
spreadsheets.
The first Excel spreadsheet is titled CSAT (Parameter Estimations). As the title suggests,
this spreadsheet deals with estimating yacht design parameters. A user enters the data listed in
Table 15 to get some yacht design parameters that include those listed in the table. A depiction
of this spreadsheet is shown in Figure 14. As the figure shows, a depiction of the general
dimensions and power curves of the yacht design is provided in this spreadsheet. Although,
Figure 14 does not show the approximate output parameters of this spreadsheet, users can see it
by simply scrolling down on the actual spreadsheet.
Table 15
Input and Output from the CSAT (Parameter Estimation) Excel Spreadsheet
Input Output
vTrial GT ∆KB
vServices
LOA
LSW Medical history
NPassenger
LWL
DWT
BMT
Trip Duration
BWL
NCrew
GMT
% LLS T
CT CB
% of MLS D S
CWP
% HLS ∇
RT CENTIMET
RE
Engine Type
VH ON CP
Propulsion and Maneuvering Systems
VSS PB, Until
Rn
Round Arc Criteria
VSt
MCRTot Fn
Figure 14. Snapshot of the Excel CSAT (Parameter Estimations) spreadsheet.
58
The second Excel spreadsheet is titled CSAT (Cost Analysis). As the title suggests, this
spreadsheet deals with the estimated cost of yacht design. The user enters the data into the CSAT
(Parameter Estimations) spreadsheet and the data listed in Table 16 into this spreadsheet to get
some yacht design cost parameters that include those listed in the table. A depiction of this
spreadsheet is shown in Figure 15. As the image shows, a pie chart of CTO and BTotal
components is provided in this spreadsheet. The bottom left image in this spreadsheet shows a
cash flow report of the yacht design over its lifetime. This number can be used to analyze the
time in which the ship becomes profitable (if ever). The image on the far right side of this
spreadsheet shows a specific variable as a function of cabin settings (i.e. the percentage of all
cabins arranged by a particular type). These variables can be specified as NPV, BCR, GT, or
others by varying the list box and/or clicking the button above the image. One use of this number
is to evaluate a specific cabin setup (e.g. 100% LLS, 0% MLS, and 0% HLS) that shows the
largest NPV given the inputs specified in the CSAT (Parameter Estimate) and CSAT (Cost
Analysis) spreadsheets.
Although, Figure 15 does not show the estimated cost output of this spreadsheet, users can see
it by simply scrolling down on the actual spreadsheet.
Table 16
Input and Output from CSAT (Cost Analysis) Excel Spreadsheet
Input Output
rNPV
BO &
O, MLS
TLife BCR
BO &
O, HLS
TVoyage IRR
CCTO
NPorts
CC CO&O
TPort
CTO
CFuel
CFuel per metric ton
BTotal
CP & R
BTicket LLS per hari
BTicket, LLS CFood
BTicket MLS per hari
BTicket,
MLS
GIZMO
BTicket HLS per day
BTicket, HLS
Average Passenger Revenue
BO & O, LLS
Figure 15. Snapshot of the CSAT (Cost Analysis) Excel spreadsheet.
59
With regard to the third Excel spreadsheet, titled CSAT (Miscellaneous Data), this
spreadsheet deals with the miscellaneous data needed to support the algorithms of the other two
spreadsheets. In this spreadsheet, users can also see the data point values of the variables that
appear plotted on the rightmost image of the CSAT (Cost Analysis) spreadsheet as a function of
the living room settings.
60
Chapter 6 – Results and Analysis
Net Now Value Analysis Approach
NPV is estimated for yacht design to estimate the most profitable yacht design and pool
of each design. The design of a cruise ship is determined by its passenger carrying capacity with
double occupancy. Yacht designs with NPassenger equal to 750, 1500, 3000, and 4500 were
analyzed, as listed in Table 17. This yacht design is referred to as Yacht Design, A, B, C, or D in
this thesis. The NPassengers range is chosen in such a way that it covers most of the built
yachts in operation today.
Table 17
Yacht Design
Yacht Design NPassenger
A750 Passengers
B1,500 Passengers
C3,000 Passengers
D4,500 Passengers
Note. Each yacht is determined by its NPassengers.
For the yacht design analyzed (see Table 17), the variables listed in Tables 3, 13, and 18
are considered fixed. One of the reasons the test and service speeds are set at 22.5 kts and 21.0
kts respectively is because these values are prototypical of yachts. The velocity criterion is also
associated with the methodology used to predict residual resistance where the prediction is valid
for an Fn value between 0.15 and 0.45 (see Appendix B). Each yacht design is specified to
have two propulsion units as these are prototypical of yachts. Note that all aircraft carriers have
at least two propulsion units of which 19 out of 21 vessels have two. The duration of the voyage,
the number of ports per voyage, and the number of hours per port are set at 7 days, 3 ports, and 6
hours respectively as these are the average values in 2014. The reasons for the return rate and the
age of the ship are 10% and 30 years respectively discussed in Chapter 4.
Table 18
Fixed Variables of Cruise Design
Fixed Variables Value
vTrial 22.5 kts
vServices 21.0 kts
# Propulsion Unit 2 units
TVoyage 7 days
NPorts 3 Ports
TPort 6 hours
r10%
N30 years
61
For the yacht designs analyzed (see Table 17), the NPV is estimated for the set of
design features of each design. The design feature set is defined as the specific synthesis of the
cabin space arrangements, engine type, propulsion and maneuver system type, and circular bow
criteria (see Table 19) that a yacht is designed to have.
Table 19
Some Components That Characterize the Assembly of Design Features
Engine
Type
Types of Propulsion
and Maneuver
Systems
Round Arc
Criteria
Diesel Gas Turbine Tradisional Under Occurred N/A
The cabin arrangement of a yacht design is defined as the percentage of each cabin type
relative to all the cabins that the yacht design has. The cabin types analyzed are LLS, MLS, and
HLS where their characteristics are listed in Tables 3 and 13. Examples of specific cabin
arrangements are 82% LLS, 14% MLS, and 4% HLS. The cabin arrangements of the yacht
design were analyzed with the addition of 2% of each cabin type This shows a total of 1,326
possible cabin arrangements
For each of the 1,326 aircraft cabin settings, variations in other design feature assembly
components were analyzed (i.e. engine type, propulsion and maneuver system type, and circular
arc criteria). There are eight possible combinations of assembly components of the design
features listed in Table 19. Each specific combination is defined as a combination of EP&B
design features in this thesis from this point on. The combination of EP&B design features
relating to yachts is referenced to specific codes, as listed in Table 20.
Each code consists of one letter and three numbers. The letters in each code represent the
appropriate yacht design (see Table 17). The first number in each code indicates whether the ship
has a diesel engine (1) or a gas turbine engine (2). The second number in each code indicates
whether the ship has a traditional propulsion and maneuvering system (1) or a pod (2). The third
number in each code indicates whether the ship has a rounded bow (1) or not (2). The possible
number of combinations of EP&B design features and cabin type arrangements shows each yacht
design was analyzed for a total of 10,608 (i.e. 8 1,326) different design feature sets.∗
Table 20
EP&B Design Feature Combination
Yacht
Design EP&B Design Feature Combination
AA.1.1.1 A.1.2.1 A.1.1.2 A.1.2.2 A.2.1.1 A.2.1.2 A.2.2.1 A.2.2.2
BB.1.1.1 B.1.2.1 B.1.1.2 B.1.2.2 B.2.1.1 B.2.1.2 B.2.2.1 B.2.2.2
CC.1.1.1 C.1.2.1 C.1.1.2 C.1.2.2 C.2.1.1 C.2.1.2 C.2.2.1 C.2.2.2
DD.1.1.1 D.1.2.1 D.1.1.2 D.1.2.2 D.2.1.1 D.2.1.2 D.2.2.1 D.2.2.2
Note. There are eight possible combinations of EP&B design features for each yacht design analyzed.
62
Net Present Value Results and Cruise Design Analysis
Given that the variables in Tables 3, 13, and 18 remain, surface plots are constructed for
Yacht Designs A, B, C, and D to display the set of design features of each yacht design that
exhibit the largest NPV (i.e. the most advantageous), as shown in Figures 16-19 respectively.
The x-axis of each image located on the bottom right side represents the percentage of medium
luxury cabins (i.e. MLS) that the yacht design has. The y-axis of each image located on the
bottom left side represents the lower percentage of luxury cabins (i.e. LLS) that the yacht design
has. The z-axis located to the left of each image represents the NPV. The higher percentage of
luxury cabins (i.e. HLS) is not represented by the axis, however, it is implicit. For example, the
coordinates pertaining to a design feature set of 10% LLS and 20% MLS indicate that this set
has 70% HLS. Each of the eight EP&B design feature combinations for each yacht design is
plotted individually. Thus, the combination of EP&B design features for a particular cabin
setting that shows the largest NPV is considered to be the most advantageous combination of
EP&B design features on this cabin setup. In addition, the cabin arrangement and the
combination of EP&B design features (i.e. assembly of design features) that show the largest
NPV of the yacht design is considered to be the most advantageous set of design features of that
yacht design.
The cabin arrangements showing the highest and lowest NPV for each combination of
EP&B design features of the yacht design are listed in Table 21. The value in parentheses in the
cell box corresponds to the percentage of each cabin type that the yacht design has with NPV
(i.e. LLS%, MLS%, HLS%).
Table 21
Minimum and maximum NPV for each combination of EP&B design features
Yacht Design
A B D
EP&B NP
V
mini
mu
m
NPV
Max
NP
V
mini
mu
m
NPV
Max
NP
V
mini
mu
m
NPV
Max
NP
V
mini
mu
m
NPV
Max
1.1.1 -$316.9
million
(0,0,100)
-$215.1
million
(82,16,2)
-$325.3
million
(0,0,100)
-$139.4
million
(100,0,0)
-$88.8
million
(0,4,96)
$49.4
million
(100,0,0)
$162.0
million
(0,60,40)
$267.6
million
(100,0,0)
1.2.1 -$261.6
million
(0,0,100)
-$177.5
million
(88,6,6)
-$205.6
million
(0,0,100)
-$53.7
million
(100,0,0)
$48.6
million
(0,64,36)
$155.5
million
(100,0,0)
$318.3
million
(2,46,52)
$388.7
million
(100,0,0)
1.1.2 -$394.4
million
(0,0,100)
-$252.2
million
(82,16,2)
-$430.4
million
(0,0,100)
-$168.7
million
(100,0,0)
-$205.4
million
(0,0,100)
-$37.9
million
(100,0,0)
$40.7
million
(50,0,50)
$166.3
million
(100,0,0)
1.2.2 -$294.1
million
(0,0,100)
-$194.1
million
(82,16,2)
-$300.3
million
(0,0,100)
-$117.1
million
(100,0,0)
-$49.1
million
(0,30,70)
$75.8
million
(100,0,0)
$215.8
million
(26,2,72)
$297.3
million
(100,0,0)
2.1.1 -$450.9
million
(12,60,28)
-$346.0
million
(82,16,2)
-$484.7
million
(0,0,100)
-$240.0
million
(100,0,0)
-$330.9
million
(0,0,100)
$155.5
million
(100,0,0)
-$67.5
million
(0,0,100)
$106.2
million
(100,0,0)
2.1.2 -$559.8
million
-$387.6
million
-$648.3
million
-$278.5
million
-$434.1
million
-$188.4
million
-$265.9
million
-$52.5
million
63
(0,0,100) (82,16,2) (0,0,100) (100,0,0) (0,0,100) (100,0,0) (0,0,100) (100,0,0)
2.2.1 -$359.9
million
(0,0,100)
-$277.3
million
(82,16,2)
-$377.8
million
(0,0,100)
-$177.8
million
(100,0,0)
-$114.0
million
(0,0,100)
$40.9
million
(100,0,0)
$96.4
million
(50,0,50)
$214.9
million
(100,0,0)
2.2.2 -$403.5
million
(12,60,28)
-$315.4
million
(82,16,2)
-$451.8
million
(0,0,100)
-$210.8
million
(100,0,0)
-$276.4
million
(0,0,100)
-$89.5
million
(100,0,0)
-$1.36
million
(0,0,100)
$145.1
million
(100,0,0)
Note. The value in parentheses in the cell box corresponds to the percentage of each cabin type that the yacht
design has with NPV (i.e. LLS%, MLS%, HLS%).
64
Figure 16. NPV for each design feature set of Yacht Design A. Legend right image shows a combination of EP&B
design features respectively.
Figure 17. NPV for each design feature set of Yacht Design B. Legend right image shows the combination of
EP&B design features of each.
% LLS % MLS
% LLS % MLS
NPV ($ M)
NPV ($ M)
65
Figure 18. NPV for each design feature set of Yacht Design C. Legend right image shows a combination of EP&B
design features respectively.
Figure 19. The NPV for each design features the Yacht Design set D. Legend right image shows the combination
of the respective EP&B design features.
% LLS % MLS
% LLS % MLS
NPV ($ M)
NPV ($ M)
66
The analysis of Figure 16-19 shows that cab arrangements pertaining to a combination of
EP&B 1.2.1 design features (i.e. diesel engines, propulsion systems and pod maneuvers, and
round arc criteria) result in greater NPV than other EP&B design feature combinations with the
same cab setup. The combination of EP&B 1.2.2 design features (i.e. diesel engine, propulsion
system and pod maneuver, and no bulb arc) and 1.1.1 (i.e. diesel engine, traditional propulsion
and maneuver system, and round bow) results in the second and third largest NPV for a given
cabin arrangement when compared to any other EP&B design feature combination. These results
and ideas are analyzed in more detail in the following sections.
Analysis of the Most Profitable EP&B Design Feature Combinations
Implications of Machine Type
As previously stated, for certain cabin settings, the combination of EP&B design
features 1.2.1, 1.2.2, and 1.1.1 results in a greater (i.e., more advantageous) NPV value in the
order listed. The assembly component of the common design features among the combination
of EP&B design features is the type of engine that is a diesel engine.
One of the reasons diesel engines promote a greater NPV value than gas turbine engines
is because the CFuel of diesel engines is lower than that of gas turbines. It is attributed to the
specific fuel rate of each type of engine where SFR is the rate at which fuel is consumed per unit
of power delivered. The SFR value used in this thesis is based on the actual engine power output
and is between 0.173-0.185 kg/kW-h for diesel engines and between 0.227-
0.270 kg/kW-h for gas turbine engines.
The surface plot of the total cost of ship life fuel (CFuel, Life) for each yacht design
set feature design supports the idea of SFR. CFuel, Life is plotted for each design feature of
the Yacht Design pool C as a function of the aircraft cabin setup, as shown in Figure
20. The figure illustrates that, for a given cabin setting, CFuel, Life will be lower for a
combination of EP&B 1.2.1 design features than any other combination of a Yacht Design C.
This shows the consequences of the selection of a gas turbine engine because CFuel, Life for
a combination of EP&B C.2.2.1 design features is greater than C.1.2.1 for a particular cabin
setting. Therefore, the higher SFR of the gas turbine engine compared to the diesel engine
results in a higher CFuel, Life for this yacht design.
Another interesting aspect of Figure 20 is that for a given cabin setting, the C Yacht
Design will show CFuel, Life for a combination of EP&B 2.2.1 design features that are
larger (i.e. gas turbine engines, propulsion and pod maneuver systems, and rounded bows) than
those
1.2.2 (i.e. diesel engine, propulsion system and pod maneuver, and no round arc). This shows
an advantage in terms of CFuel reduction, Life having a round bow for yacht design is
offset by the disadvantage of CFuel improvement, Life as a result of having gas
67
turbine engine. Although, CFuel, Life was only surface plotted for Yacht Design C, these
results were consistent among the yacht designs analyzed.
Figure 20. CFuel, Life for each design features the Yacht Design set C. Legend right image shows the
combination of EP&B design features of each.
Figures 20 and 21 illustrate the importance of reducing the CFuel, Life on Cruise
Ship Design C total ship operating costs (CTO, Life). Figure 21 illustrates the percentage of
CTO , Life comprising CFuel, Life for each possible design feature assembled from
Yacht Design C. As the figure shows, CFuel, Life is about 20-40% of CTO, Life. To put
this in perspective, this could mean a reduction of approximately $550 million in CTO , Life if
the ship's design feature assembly is characterized as 100% HLS and EP&B C.1.2.1 design
feature combination compared to 100% HLS and EP&B C.2.2.1 design feature combination. In
addition, in this scenario, the NPV is -$114.0 M and $57.3 M for C.2.2.1 and C.1.2.1,
respectively. Therefore, the type of engine in this case determines whether the ship will be
profitable or not if it is applied. This idea exemplifies how NPV analysis can be used to evaluate
how design feature decisions at the initial design stage can ultimately change a ship's ability to
be profitable.
% LLS % MLS
CFuel, Life
($M)
68
Figure 21. % of the CTO, The Life of the CFuel, Life for the design features of the Yacht Design
collection C. Legend right of the image shows the combination of the EP&B design features of each.
Although, cost analysis is the focus of this thesis, it is important to note some
advantages of gas turbine engines over diesel engines that can encourage ship designers to
consider them. Some of the advantageous attributes of gas turbine engines are that they have a
larger power-to-weight ratio and are smaller in size compared to diesel engines with similar
power output. This can be beneficial for yachts because the extra space that is excavated by
choosing a gas turbine engine instead of a diesel engine can be used for other functions of the
ship. In addition, the waste heat of gas turbine engines can be exploited for onboard service
(Molland, 2008). Finally, if speed is critical, it can be difficult to meet the boat's power
requirements and/or meet emissions regulations using diesel engines.
Implications of Propulsion Systems and Maneuvers
Figure 16-19 shows that for a given cabin setting, the EP&B 1.2.1 design feature
combination of the yacht design will always exhibit a greater NPV than any other EP&B design
feature combination. The reason diesel engines are more conducive to profitable ship designs
(i.e. greater NPVs) than gas turbine engines has been discussed in the previous sub-section. In
this sub-section, the focus is on analyzing why pod propulsion and maneuvering systems
promote more profitable yacht designs than traditional propulsion and maneuvering systems.
Again, note that all yacht designs analyzed in this thesis are assumed to have electric engines.
%LLS % MLS
CTO, Life consists ofFuel C, Life
(%)
69
Typically, traditional propulsion and maneuvering systems will consist of a long shaft
line and rudder that will result in a wetter surface of the boat. Because the S is improved, the
ship's RT is also increased. On the other hand, the pod propulsion and maneuver system does
not have a long shaft line because the motor is inside the pod unit and the propeller is directly
connected to the motor shaft. In addition, the pod unit can rotate 360º, thus, ships with this
system are likely not to need rudder. For this reason, pod propulsion and maneuver systems
typically have lower S and RT than traditional propulsion and maneuver systems. This idea is
supported in Figure 22 where the reduction in RT (in vTrial) that the ship would show if the
combination of EP&B 1.2.1 design features was selected instead of 1.1.1 plotted surface. As the
figure shows, each yacht design exhibits an RT reduction if a pod propulsion and maneuver
system is chosen instead of a traditional propulsion and maneuver system, regardless of cabin
type The RT reduction is approximately between 3-6% among yacht designs. Since the
reduction of RT results in a reduction in CFuel, Life, this is one of the reasons why the
propulsion system and maneuvering pods are conducive to more profitable yachts.
Figure 22. Reduce RT if a combination of EP&B design features 1.2.1 is selected instead of 1.1.1. The legend on
the right of the image shows a specific yacht design.
Another advantageous attribute of the pod propulsion and maneuver system is that the
propeller can be mounted lower under the stern than traditional propulsion and maneuver
systems. It improves mechanical and hydrodynamic efficiency. In addition, since the motor is
inside the pod unit, the usable volume of the boat can be used for more purposes. An example
of this is when the traditional Carnival Elation propulsion and maneuver system was replaced
by a pod propulsion and maneuver system. By doing this, ships now have the ability to have
incinerators. In fact, it is the first cruise ship to have a propulsion system and pod maneuvers.
%LLS % MLS
RT Reduction (%)
70
Although, the propulsion system and pod maneuvers are declared conducive to more
profitable yachts, it is important to note the caveat of this idea. This means that pod units have
historically had reliability issues that include issues with electrical contamination, bearings,
shaft sealing, and lubricating oil. If a cruise ship has pod problems, it will likely need to be dry-
docked for repair. According to Stieghorst (2013), this is associated with pod units that are very
compact and difficult to repair at sea. For example, the pod unit on the Celebrity Cruises Infinity
cruise ship had a bearing problem and the ship had to be evacuated emergency (Bearing Failure
Sidelines Cruise Ship Again, 2005). Obviously, if a cruise ship docks dry, it relinquishes its
ability to generate revenue, thus, a very problematic problem for cruise lines whose profitability
depends on its ships keeping their tight schedules. In fact, reliability issues pushed Carnival
Cruise Lines away from a fully pod system where their cruises shipped after 2005 (as of 2014)
did not have them. Nonetheless, the reliability of the pod propulsion and maneuvering system
has improved over time and may be the reason why Carnival Cruise Lines' new ship Carnival
Vista will be built with a pod system.
Implications of a Round Arc
The reasons why diesel engines and propulsion systems and pod maneuvers are
conducive to more profitable yachts have been discussed. This section focuses on other design
features of the EP&B 1.2.1 design feature combination that promotes greater NPV value. That
is, the effect of a rounded bow on the profitability of yachts.
The round arc modifies the flow of water around the hull to reduce RT. In the case of
smoother vessels faster, this means a reduction in wave-making resistance. In the case of slower
ships, this tends to mean a reduction in viscous resistance (Hudson, Molland, & Turnock, 2011).
A round arc is effective in terms of reducing RT when this reduction in resistance by the bulb is
greater than the increase in skin friction resistance caused by the addition of a wetted bulb
surface. As the speed of the ship decreases, the resistance of subsequent wave-making will
decrease. Thus, round arcs are usually more effective at higher speeds.
To evaluate the implications of the circular bow on the profitability of the yacht, the
reduction of RT (in vTrial) due to the addition of the circular bow was analyzed, as shown
in Figure
23. With regard to this figure, the reduction in RT indicated by each yacht design if the
EP&B 1.2.1 design feature combination is selected instead of 1.2.2 plotted surface. As the figure
shows, the yacht design will show a reduction in RT of about 6-12% if they have a rounded
bow than if they don't. The RT reduction results in the next CFuel, Life reduction. This is
why the rounded bow is conducive to a more profitable yacht design.
71
Figure 23. RT reduction if EP&B 1.2.1 design feature combination is selected instead of 1.2.2. The legend on the
right of the image shows a specific yacht design.
Implications of Passenger Carrying Capacity
Figure 16-19 illustrates the NPV of a particular cabin setup increasing as
NPassengers increase. This is because as the number of NPassenger increases,
BTotal will increase more than the total cost of the ship (CTotal). Consider the case where
NPassengers for the yacht design features a pool that complies with C.1.2.1 and 100% LLS
is increased from 3,000 to 3,002 passengers. With this increase in NPassenger, the ship's
GT will also increase as it is a function of the VSt. CC and CTO, Life will also increase so
that the average CTotal increase is almost $211 per day. However, by increasing
NPassengers by 2 passengers, there is also an average increase in BTotal of almost $420
per day. This resulted in a net profit of $209 per day. This effect is also evident for the assembly
endpoint of the opposite design features that are compliant with C.1.2.1 and 100% HLS. This
means that by increasing NPassengers by 2 passengers, the BTotal increase (i.e. $743 per
day) is greater than the CTotal increase (i.e. $505 per day) resulting in a net profit of
$238 per day.
As NPV increases as NPassengers increase, this seems to indicate very large yacht
designs in terms of GT are the most profitable in terms of NPV. Obviously, this is unrealistic.
One of the ship size restrictions can be based on the requirements of the ship that can transit
through a particular waterway. For example, in order for a ship to travel through the Panama
Canal, the BWL of a ship must be less than 32.3 m in order to pass through the canal lock. In
addition, having a larger ship size can limit the ports where it can dock because its T can increase
to the point where the ship can be prone to running aground. Other
%LLS % MLS
RT Reduction (%)
72
An aspect to consider is that as NPassengers increase, it is more difficult to fill ships with
double occupancy carrying capacity unless demand will increase as well. Up to this point, the
percentage of Yacht Design NPassengers D for the EP&B 1.2.1 design combination
that needs to be filled in for its NPV to be equal to Yacht Design C at 100% of its NPassengers
is analyzed, as shown in Table 22. For this analysis, NPV is analyzed at the endpoint of the
cabin space setup.
Table 22
Consequences on NPV if it does not reach the specified NPassengers of the yacht design
100% LLS 100% MLS 100% HLS
Yacht Design D 89.9% Full 92.1% Full 94.1% Full
Design of the C NPV
Cruise Ship
$155.5 million $87.2 million $57.3 million
Note. This table shows the percentage of Yacht Design D NPassengers that must be filled to the Same NPV
of Yacht Design C in its NPassengers. This analysis applies to the combination of EP&B 1.2.1 design
features.
As shown by Table 22, Yacht Design D must be relatively full in order to be considered
a more profitable investment than Yacht Design C. That is, 89.9% (i.e. at 100% LLS), 92.1%
(i.e. at 100% MLS), or 94.1% (i.e. at 100% HLS) of Yacht Design D NPassengers must be
met in order for its NPV to at least match Yacht Design C on its full NPassengers.
As Table 21 shows, the NPV is negative for each cabin setting that corresponds to the
A.1.2.1 and B.1.2.1. On the other hand, the NPV is positive for each cabin arrangement that
corresponds to C.1.2.1 and D.1.2.1. Therefore, on some NPassengers between Yacht
Design B and D, the NPV will be greater than zero. It is analyzed for a combination of EP&B
1.2.1 design features because the NPV is greater for this combination than for others for a
particular cabin setting. Given the assumptions in Tables 3, 13, and 18, this particular
NPassengers are estimated to be 2,086 passengers with a suitable cabin arrangement of
100% LLS, 0% MLS, and 0% HLS.
Implications of Cabin Setup
As stated earlier, on certain cabin settings, the combination of EP&B 1.2.1 design
features of the yacht design will always show a greater NPV than any other combination of
EP&B design features. NPV according to the cabin arrangement of the EP&B 1.2.1 design
feature combination plotted surface for each yacht design to estimate the set of design features
considered most advantageous. The results are shown in Figure 24-27. The color bar located to
the right of each image corresponds to the NPV value.
73
Figure 24. The NPV for the EP&B design shows the 1.2.1 combination of Yacht Design A. The color map located
to the right of the image represents the NPV value.
Figure 25. The NPV for the EP&B design shows a combination of 1.2.1 from the Yacht Design B. The color map
located to the right of the image represents the NPV value.
NPV ($ M)
% LLS % MLS
NPV ($ M)
% LLS % MLS
NPV ($ M)
NPV ($ M)
74
Figure 26. The NPV for the EP&B design shows the 1.2.1 combination of the Yacht Design C. The color map
located to the right of the image represents the NPV value.
Figure 27. The NPV for the EP&B design shows the 1.2.1 combination of the Yacht Design D. The color map
located to the right of the image represents the NPV value.
NPV ($ M)
% LLS % MLS
NPV ($ M)
% LLS % MLS
NPV ($ M)
NPV ($ M)
75
The set of design features that show the largest NPV (i.e. the most profitable) of each
yacht design is listed in Table 23. Also, the main physical and performance characteristics of this
yacht design regarding the most advantageous set of design features are listed in Table 24.
Table 23
Assemblage Feature Design That Shows the Largest NPV for Every Cruise Design
Cabin Setup
Yacht Design NPV EP&B Design Feature
Combination
LLS
(%)
MLS
(%)
HLS
(%)
A-$177.5 million A.1.2.1 88% 6% 6%
B-$53.7 million B.1.2.1 100% 0% 0%
C$155.5 million C.1.2.1 100% 0% 0%
D$388.7 million D.1.2.1 100% 0% 0%
Table 24
Yacht Design Parameters and Assembly Most Advantageous Design Features
Yacht Design
Parameter A B C D
GT 24,621 48,993 97,986 146,978
LOUDSPEA
KER
177,5 m 225,6 m 287,2 m 330,8 m
LPP 158,7 m 201,7 m 256,9 m 295,9 m
LWL 161,9 m 205,8 m 262,0 m 301,8 m
BWL 23,3 m 28,3 m 34,5 m 38,7 m
T6,2 m 6,9 m 7.75 million 8,4 m
D14,9 m 18,0 m 21,7 m 24,3 m
∇
13.772 mm3 25.791 m3 48.523 m3 70.227 m3
VTot 78.050 m3 155.307 m3 310.614 m3 465,921 m3
VH 43.860 m3 88.640 m3 176.319 mm3 261.762 m3
VSS 34.190 m3 66.667 m3 134.295 m3 204.159 m3
∆
14.117 T 26.436 T 49.736 T 71.983 T
MCRTot 36,000 kW 50,400 kW 50,400 kW 63,000 kW
GMT 1,30 m 1.36 meters 1.01 meters 1.35 meters
NPassenger 750 passengers 1,500 passengers 3,000 passengers 4,500 passengers
NCrew 263 crew members 524 crew members 1,048 crew members 1,573 crew members
VSt 17.484 m3 34.791 m3 69.581 m3 104.372 m3
% LLS 88% 100% 100% 100%
% of MLS 6% 0% 0% 0%
% HLS 6% 0% 0% 0%
With regard to Yacht Design A, NPV was analyzed to be the largest (i.e. -$177.5M) on a
combination of EP&B 1.2.1 design features and cabin arrangements of 88% LLS, 6% MLS, and
6% HLS. On the other hand, NPV is best for Yacht Design B, C, and D on a combination of
EP&B 1.2.1 design features and cabin arrangements of 100% LLS, 0% MLS, and 0%
76
HLS has values of -$53.7M, $155.5M, and $388.7M, respectively. Relatively large NPV
increases for small variations in aircraft cabin settings, as seen in Figure 24-27, are attributed to
the CC estimated through multi-linear regression of the GT and MCRTot predictors. In
addition, it is assumed that MCRTot must equal or exceed PB, Tot to ensure that the ship's
power needs will be met. For example, consider a case where PB,Tot is estimated
51,000 kW for the yacht design which is characterized as greater than 40,000 GT and conforms
to the combination of EP&B 1.2.1 design features. The ship is assumed to require a number of
12,600 kW diesel engines to produce the ship's power. Four of these diesel engines are not
enough as this would show a slightly less MCRTot of 50,400 kW
from PB, Tot. Thus, five engines were used instead, showing an MCRTot of 63,000 kW.
The Yacht Design A has a different cabin arrangement (being 88% LLS, 6% MLS, and
6% HLS) which shows the largest NPV (-$177.5M) than any other yacht design for EP&B 1.2.1
Design Feature Combination. It is a by-product of the RT and BTicket characteristics of this
particular set of design features from Yacht Design A.
Figure 28 shows the RT and NPV (i.e. via color map) for the combination of EP&B design
features
1.2.1 Yacht Design A (i.e. A.1.2.1). Analyzing the data points in this figure shows that the set of
design features that have the largest NPV (i.e. 88% LLS, 6% MLS, and 6% HLS) has the second
lowest RT, which is 904.5 kN. The design feature set corresponding to 82% LLS, 16% MLS,
and 2% HLS had the lowest RT and the second largest NPV was 903.6 kN and
-$177.6 M, respectively.
cluster. In more detail, this set of design features relating to L/∇1/3 is equal to the 6.5 or 7.0
residual resistance diagram of Guldhammer and Havarld (1974) (see Appendix B). As this
diagram shows, CR, The chart is larger for a given Fn and CP when the L/∇1/3
decreases.
The set of design features that show the two largest NPV values has a value
L/∇1/3 is rounded to 7.0, thus, the CR value , the diagram is relatively favorable. For Fn and
L/ given
∇1/3, CR, Declining chart as CP decreases. The design feature set pertaining to the two
largest NPV values for A.1.2.1 has the lowest round CP value (i.e. 0.625) among the design
feature sets measured. In addition, because this design feature assembly is less luxurious in terms
of cabin arrangement than most of their counterparts, their GT and VH are lower resulting in a
relatively low wet surface. As illustrated in Figure 29, the multiplication of CR, the S times
diagram is very low for these two sets of design features, thus, their preference for the
relatively low RT value. The color map located on the right side of the image represents the NPV
($M) value.
77
Figure 28. The RT for the EP&B design features a combination of 1.2.1 from Yacht Design A. The color map on
the right of the image represents the NPV value.
Figure 29. CR, Diagram ∙ S for the combination of EP&B 1.2.1 design features of Yacht Design A. The color map right
of the image represents the RT value.
CFuel is directly related to RT. In the lower NPassenger, the CFuel is the
larger CTO component, as shown in Figure 30 regarding the combination of EP&B design
features A.1.2.1. Because CFuel is directly related to RT, relatively low RT is conducive to
relatively low NPV, especially in
RT
(kN)
% LLS % MLS
NPV ($ M)
% LLS % MLS
RT
(kN)
CR,Diagram •
S
(m2)
78
Lower NPassengers. Nonetheless, the cabin setup A.1.2.1 that has the lowest RT also does not
have the largest NPV for Cruise Design A because certain more luxurious cabins are considered
more advantageous in terms of NPV. The design feature set pertaining to 88% LLS, 6% MLS,
and 6% HLS has a BTicket, Lifespan of $1,282 M whereas the design feature assembly
pertaining to 82% of LLS, 16% MLS, and 2% of HLS has a BTicket, Lifespan of $1,274 M
of the design feature sets pertaining to 88% LLS, 6% MLS, and 6% HLS resulting in a greater
NPV than the design feature sets pertaining to 82% LLS, 16% MLS, and 2% HLS.
Figure 30. The CTO consists of CFuel for the combination of EP&B 1.2.1 design features. Legend right of the
picture shows a specific yacht design and a combination of EP&B.
The most advantageous set of design features of Yacht Design B, C, and D in terms of
NPV is on the combination of EP&B 1.2.1 design and cabin arrangements of 100% LLS, 0%
MLS, and 0% HLS. Their NPVs were -$53.7 M, $155.5 M, and $388.7 M, respectively. As
already discussed, this was not the case with Yacht Design A. This seems to indicate, for a yacht
design with a greater NPassengers value , the gain in terms of revenue to be generated by
opting for a more luxurious cabin setup is offset by the losses from subsequent GT upgrades
resulting in greater construction and operating costs. This is because as the luxury of the nation's
cabin arrangements increases, the cost ratio dependent on BTicket-to-GT (i.e. CC,
CFuel, CP&R, CFood, and COSO) will decrease.
The BTicket-to-GT dependent cost ratio is plotted in Figure 31 for the combination
of EP&B 1.2.1 design features of each yacht design. As illustrated in the figure, the ratio of
BTicket-to-GT dependent costs are the largest on the least luxurious cabin arrangements
(i.e. 100% LLS, 0% MLS, and 0% HLS) for Yacht Designs B, C, and D. On the other hand, the
ratio
%LLS % MLS
CTO consists of CFuel (%)
79
BTicket-to-GT dependent fees are lowest in the most luxurious cabin settings (i.e. 0%
LLS, 0% MLS, and 100% HLS) for Yacht Designs B, C, and, D. This idea is not supported in
the images regarding Yacht Design A for the reasons mentioned earlier.
Figure 31. The cost depends on BTicket-to-GT for the combination of EP&B 1.2.1 design features. Legend right of
the picture shows a specific yacht design and a combination of EP&B.
CC, CP&R, CFood, COSO, and BTicket increased linearly along with the increase
in GT; however, CFuel did not follow this trend. This is because CR, the Diagram, as
predicted through the diagram of Guldhammer and Harvald (1974), is not a linear function of Fn
given a combination of CP and L/∇1/3 . In addition, this diagram shows (see Appendix B), as
Fn increases between the approximate range of 0.15
and 0.30, the rate of change CR , the diagram also increases. Assuming prototypical ship speed
given in Table 18 is set among yacht designs, by reducing NPassengers or specifying less
luxurious cabin arrangements, the size of the yacht design will be reduced. This means that the
LPP will also decrease, resulting in a greater Fn value. As Fn increases, the rate of
change of CFuel will also increase. This is the reason why CFuel is a larger percentage of
CTO because NPassengers and/or cabin luxury decrease, therefore, the reason NPV
increases
when NPassengers increase.
Yacht Designs B, C, and D have their largest NPV on the set of design features that
correspond to the combination of EP&B 1.2.1 design features and cabin arrangements of 100%
LLS, 0% MLS, and 0% HLS. On the other hand, Yacht Design A has its largest NPV on the set
of design features that conform to the combination of EP&B 1.2.1 design features and cabin
arrangements of 88% LLS, 6% MLS, and 6% HLS. This idea shows, at some of the greater
values of certain NPassengers, a set of design features that correspond to a combination of
EP&B 1.2.1 design features and a cabin setup of 100% LLS, 0% MLS, and 0% HLS will always
result in the largest NPV. Given the assumptions listed in Tables 3, 13, and 18, these
NPassengers are estimated to have 854 passengers.
%LLS % MLS
BTicket
CC+CBhanBakar+CP &R
+CFood+COSO
80
Speed Implications
Figures 16 and 17 show the negative NPV for each set of design features of Yacht
Design A or B. In addition, given the assumptions in Table 18, it is unlikely that the yacht
design will be profitable in NPassengers of less than 2,086 passengers. However, the yachts
built have NPassenger similar to the Yacht Design A and B exist and are profitable. For
example, a ship that benefits Azamara Journey has slightly fewer NPassengers (i.e. 710
passengers) than Yacht Design A. Thus, at least one fixed variable in Table 18 must be varied
in order for a yacht design with NPassengers lower than 2,086 passengers to be considered
advantageous (i.e. + NPV).
As stated, the NPV is negative for each set of design features of a Cruise Design A or B.
One way that this yacht design shows a positive NPV is to lower its speed. To this point, the
vService and vTrial required for Yacht Designs A and B to be considered as neutral
investments are analyzed, as shown in Table 25. It is analyzed for a combination of EP&B 1.2.1
design features because it is the most advantageous. Also, it is assumed that vTrial is 106%
of vService.
Table 25
The variation in ship speed required for A.1.2.1 or B.1.2.1 to have an NPV of zero
Speed Cabin Setup
Yacht
Design vService
s
vTrial LLS
(%)
MLS
(%)
HLS
(%)
A17.5 kts 18.5 kts 98% 2% 0%
B19,9 kts 21,1 kts 100% 0% 0%
The results from Table 25 show cruise speed plays an important role in determining the
yacht's ability to be profitable, especially at lower NPassenger. For example, a reduction of
about 17% in vService and 18% in vTrial suggests Yacht Design A would be considered a
neutral investment. A reduction of approximately 5% in vService and 6% in vTrial suggests
Yacht Design B will also be considered a neutral investment. This idea shows a lower
vService and vTrial, the higher the NPV. A caveat to this idea is that the cruuse ship
itinerary will affect vService as low as possible because the ship is likely to adhere to a
very tight schedule.
Implications of Cabin Ticket Prices
When evaluating NPV, BTicket values per passenger per day are assumed based on
historical data (see Table 13). This assumption can have an impact on cabin settings that
indicate the largest NPV for yacht design determined by its NPassengers.
If BTicket per passenger per day varies for one cabin type while the other remains
constant, on some BTicket per passenger per day of that cabin setup, the cabin setting
81
showing the largest NPV will change. It is analyzed for
82
The EP&B design features a combination of 1.2.1 of each yacht design, as shown in Table 26. In
this analysis, only BTcricket per passenger per day of one cabin type varied at one time. Note
that it was originally assumed BTcricket per passenger per day LLS, MLS, and HLS were
$142.29, $198.90, and $303.96, respectively. Since the cabin settings corresponding to 100%
LLS, 0% MLS, and 0% HLS are the largest NPVs for B.1.2.1, C.1.2.1, and D.1.2.1, only an
increase in BTicket MLS or HLS, or a decrease in BTicket LLS, will result in a different
cabin setting indicating the greatest NPV. On the other hand, a decrease or increase in BTicket
LLS, MLS, or HLS A.1.2.1 will result in a different cabin setup that shows the greatest NPV.
Table 26
The most favorable cabin setting sensitivity to BTicket changes
BTcricket per Passenger per Day for
each Cabin Type
Cabin
Setup
Yacht
Design NPV
LLS Certificate
($M )
passengers/day
MLS BTicket
($M )
passengers/day
HLS BTicket
($M )
passengers/day
LLS
(%)
MLS
(%)
HLS
(%)
A (LLS ↑)-$173.3 million 144.14 198.90 303.96 90% 2% 8%
A (MLS ↑)-$177.5 million 142.29 199.05 303.96 82% 16% 2%
A (HLS ↑)-$177.2 million 142.29 198.90 306.05 90% 2% 8%
A (LLS ↓)-$178.2 million 141.98 198.90 303.96 82% 16% 2%
A (MLS ↓)-$177.7 million 142.29 197.92 303.96 90% 2% 8%
A (HLS ↓)-$177.6 million 142.29 198.9 303.58 82% 16% 2%
B (MLS ↑)-$53.7 million 142.29 201.80 303.96 96% 4% 0%
B (HLS ↑)-$53.7 million 142.29 198.90 311.87 98% 0% 2%
B (LLS ↓)-$68.7 million 139.39 198.90 303.96 96% 4% 0%
C (MLS ↑)$155.5 million 142.29 201.27 303.96 96% 4% 0%
C (HLS ↑)$155.5 million 142.29 198.90 310.01 92% 0% 8%
C (LLS ↓)$131.1 million 139.92 198.90 303.96 96% 4% 0%
D (MLS ↑)$388.7 million 142.29 199.96 303.96 46% 54% 0%
D (HLS ↑)$388.7 million 142.29 198.90 305.37 82% 0% 18%
D (LLS ↓)$372.3 million 141.23 198.90 303.96 46% 54% 0%
Note. This analysis relates to the combination of EP&B 1.2.1 design features and the ↓ or ↑ symbol next to LLS,
MLS, or HLS in parentheses indicating which cabin type BTicket is varied.
As Table 26 shows, the cabin arrangements considered the most favorable are sensitive
to BTcricket variations per passenger per day. For example, only a 0.7% increase in
BTicket HLS per passenger per day for A.1.2.1 resulted in a cabin setup showing the largest
NPV changing from 88% LLS, 6% MLS, and 6% HLS to 90% LLS, 2% MLS, and 8% HLS.
Also, an increase of only 0.5% in BTicket HLS per passenger per day for
D.1.2 .1 results in a cabin setup that shows the largest NPV changing from 100% LLS, 0% MLS,
and 0% HLS to 82% LLS, 0% MLS, and 18% HLS.
Yacht Designs A and B have a negative NPV for each set of design features, given the
assumptions in Tables 3, 13, and 18. Nonetheless, yachts built with NPassenger similar to
the yacht design are known to be profitable. Improvement in
83
BTcricket per passenger per day of cabin type required for Cruise Design A and B to be
considered a neutral investment was analyzed, as shown in Table 27. In this analysis, only
BTcricket per passenger per day of one cabin type is upgraded at a time. Also, if the
BTicket per passenger per day of the LLS or MLS should be upgraded in such a way that the
BTicket per passenger per day is larger than the more luxurious cabin type, it is not
considered feasible.
Table 27
BTcricket variations required for A.1.2.1 or B.1.2.1 to have zero NPV
BTcricket per Passenger per Day for
each Cabin Type
Cabin
Setup
Yacht
Design
LLS Certificate
( $ M )
passengers/day
LLS Certificate
( $ M )
passengers/day
LLS Certificate
( $ M )
passengers/day
LLS
(%)
MLS
(%)
HLS
(%)
EP&B Design
Feature
Combination
A (↑MLS) 142.29 277.90 303.96 2% 98% 0% 1.2.1
A (↑ HLS)
142.29 198.90 405.32 0% 0% 100% 1.2.1
B (↑ LLS)
152.70 198.90 303.96 100% 0% 0% 1.2.1
B (↑ MLS)
142.29 222.86 303.96 0% 100% 0% 1.2.1
B (↑ HLS)
142.29 198.90 342.57 28% 0% 72% 1.2.1
Note. ↑ next to LLS, MLS, or HLS in parentheses indicates which cabin type BTicket per passenger per day
is upgraded.
Table 27 shows the variation of cabin-type BTickets per passenger per day
required for Cruise Design A and B to be considered a neutral investment. For example, the
BTckett A Yacht Design per passenger per day for MLS or HLS must be increased by 40%
or 33% respectively for the design to be considered a neutral investment. An increase in
BTicket LLS per passenger per day for this design is considered unreasonable because an
increase is required that results in a BTicket per passenger per day greater than the BTicket
MLS per passenger per day. The B Yacht Design B's design b-passenger per day for LLS,
MLS, or HLS must be increased by 7%, 12%, or 13%, respectively, for the design to be
considered a neutral investment. This idea suggests that as NPassengers increase, cabin
arrangements that are considered the most advantageous of yacht designs are more likely to
change due to the increase in the BTicket of certain cabin types.
Cabin Volume Implications
When evaluating NPV, cabin type volume is based on historical data. This basis can
have an impact on certain cabin arrangements that are considered most favorable for the yacht
design determined by its NPassengers. Because cabin settings that correspond to 100%
LLS, 0% MLS, and 0% HLS show the largest NPV for B.1.2.1, C.1.2.1, and D.1.2.1, if the
volume of LLS increases, or if the volume of MLS or HLS decreases, the cabin settings that
show the largest NPV of each design will change at some volume variation. On the other hand,
if the volume of LLS, MLS, or HLS is increased or decreased, the cabin setting A.1.2.1 showing
the largest NPV will change at some volume variation. Table 28 shows the results of this change
in volume. In this analysis, only the volume of one cabin type varied at a time. Also, each
84
BTicket cabin type per passenger per day is constant with the values listed in Table 13. Note
that it was initially assumed that LLS, MLS, and HLS had a volume of 40.60 m3, 65.80 m3,
and
111.86 m3 each.
Table 28
Sensitivity of the most favorable cabin settings to changes in cabin volume
Volume of Each
Cabin Type
Cabin Setup
Yacht
Design NPV Volume LLS
(m3)
Volume MLS
(m3)
Volume MLS
(m3)
LLS
(%)
MLS
(%)
HLS
(%)
A (↑ LLS)
-$177.6 million 40.611 65.800 111.860 82% 16% 2%
A (↑ MLS)
-$177.7 million 40.600 66.968 111.860 90% 2% 8%
A (↑ HLS)
-$177.6 million 40.600 65.800 112.028 82% 16% 2%
A (↓ LLS)
-$174.9 million 40.068 65.800 111.860 90% 2% 8%
A (↓ MLS)
-$177.5 million 40.600 65.688 111.860 82% 16% 2%
A (↓ HLS)
-$177.2 million 40.600 65.800 110.656 90% 2% 8%
B (↑ LLS)
-$68.6 million 41.812 65.800 111.860 96% 4% 0%
B (↓ MLS)
-$53.7 million 40.600 64.932 111.860 98% 2% 0%
B (↓ HLS)
-$53.7 million 40.600 65.800 108.920 98% 0% 2%
C (↑ LLS)
$126.5 million 41.804 65.800 111.860 82% 18% 0%
C (↓ MLS)
$155.6 million 40.600 64.764 111.860 96% 4% 0%
C (↓ HLS)
$155.5 million 40.600 65.800 109.144 92% 0% 8%
D (↑ LLS)
$373.6 million 41.020 65.800 111.860 98% 2% 0%
D (↓ MLS)
$389.1 million 40.600 65.324 111.860 44% 56% 0%
D (↓ HLS)
$388.9 million 40.600 65.800 111.213 82% 0% 18%
Note. This analysis deals with the combination of EP&B 1.2.1 design features and the ↓ or ↑ symbol next to LLS,
MLS, or HLS in parentheses indicating which cabin type volume is varied.
Table 28 shows the cabin arrangement that is considered the most advantageous
sensitive to variations in cabin volume. For example, only a 0.011 m3 increase in LLS volume
is required to change the most favorable A.1.2.1 cabin setup from 88% LLS, 6% MLS, and 6%
HLS to 82% LLS, 16% MLS, and 2% HLS. Also, only improvements
0.42 m3 in LLS volume is required to change the most favorable cabin settings
D.1.2.1 from 100% LLS, 0% MLS, and 0% HLS to 98% LLS, 2% MLS, and 0% HLS.
Yacht Designs A and B have a negative NPV for each set of design features, given the
assumptions in Tables 3, 13, and 18. Nonetheless, yachts built with NPassenger similar to
the yacht design are known to be profitable. The reduction in cabin type volume required for
Yacht Designs A and B to be considered a neutral investment was analyzed, as shown in Table
29. In this analysis, only the volume of one cabin type is reduced at a time. Also, if the volume
of the MLS or HLS has to be reduced in such a way that the volume is lower than that of a less
luxurious cabin, it is not considered feasible.
85
Table 29
Variation in cabin volume required for A.1.2.1 or B.1.2.1 to have zero NPV
Volume of Each
Cabin Type
Cabin
Setup
Yacht
Design
LLS
Volume
(m3)
MLS
Volume
(m3)
MLS
Volume
(m3)
LLS
(%)
MLS
(%)
HLS
(%)
EP&B Design
Feature
Combination
A (↓ LLS)
23.044 65.800 111.860 100% 0% 0% 1.2.1
A (↓ HLS)
40.600 65.800 75.576 0% 0% 100% 1.2.1
B (↓ LLS)
35.924 65.800 111.860 96% 2% 2% 1.2.1
B (↓ MLS)
40.600 55.776 111.860 0% 100% 0% 1.2.1
B (↓ HLS)
40.600 65.800 98.224 10% 0% 90% 1.2.1
Note. ↓ next to LLS, MLS, or HLS in parentheses indicates which cabin type volume is reduced.
Table 29 shows the variation in cabin type volume required for Cruise Design A and B to
be considered a neutral investment. For example, the cabin volume of a Yacht Design A for an
LLS or HLS must be reduced by 43% or 32%, respectively, for the design to be considered a
neutral investment. Reducing the MLS volume for this design is considered unreasonable
because the reduction results in less volume than the HLS volume is required. The cabin volume
of Yacht Design B for LLS, MLS, or HLS must be reduced by 12%, 15%, or 12%, respectively
for the design to be considered a neutral investment. This idea suggests that as NPassengers
increase, the cabin arrangements that are considered the most advantageous of yacht designs
are more likely to change due to a decrease in the volume of certain cabin types.
Initial Stability Analysis
As mentioned, the focus of the thesis is to evaluate the implications of the selection of
certain design features at the initial design stage on the yacht's potential profitability.
Nonetheless, a ship designer should not rely solely on profitability as the sole indicator of the
survival of an early yacht design.
Stability is another important aspect to consider in the initial design stage. To date,
GMT is estimated to be a combination of EP&B 1.2.1 design features of each yacht design. The
results are plotted on the surface in Figure 32. As the figure shows, the GMT of each cabin
setting regarding the combination of EP&B 1.2.1 design features of each yacht design is
between 0.4 m and 1.4 m values. In addition, these GMT values exceed the GMT
requirement of 0.15 m specified in IMO Resolution A.749 (1993) regarding passenger and
cargo ships.
86
Figure 32. GMT for EP&B designs features a 1.2.1 combination of each yacht design. Legend right of the picture
shows a specific yacht design and a combination of EP&B.
Admittedly, there are many other aspects of stability analysis that are not done in this
thesis that could affect the viability of early yacht designs. Thus, just as a comprehensive
profitability analysis is conducted, in the industry a comprehensive stability analysis will also
be carried out.
Comparison Results with Aircraft Carriers
The validity of the technique used to estimate the physical characteristics and design
performance of the yacht is assessed by comparing the actual parameter values of the parent
yacht with its estimated values. This is achieved for the Carnival Dream, Oasis of the Seas, and
Norwegian Breakaway cruises, as shown in Table 30.
% LLS % MLS
GMT
(m)
87
Table 30
Comparison of Estimated and Actual Parameters of the Mother Yacht
Aircraft Carrier
Mimpi karnaval Oasis Loud Norwegian Partition
By. Estimated Current %
Error Estimated Current %
Error Estimated Current %
Error
LOU
DSPE
AKER
323,5 m 305,6 m 5.9% 391,9 m 361,6 m 8.4% 327,5 m 324,0 m 1.1%
LWL 295,1 m 274,6 m 7.5% 357,4 m 336,6 m 6.2% 298,7 m 306,1 m 2.4%
LPP 289,4 m 269,2 m 7.5% 350,4 m 330,0 m 6.2% 292,8 m 300,1 m 2.4%
BWL 38,0 m 37,2 m 2.2% 44,5 m 47,0 m 5.3% 38,4 m 39,7 m 3.3%
T8.35
million
8.20
meters
1.8% 9.55
million
9,10 m 4.9% 8,37 m 8.30
meters
0.8%
GT 137,872 128,251 7.5% 238,815 225,282 6.0% 142,694 145,645 2.0%
PB,P 44,4 MW 44,0 MW 0.9% 56,3 MW 60,0 MW 6.3% 36,5 MW 35 MW 4.3%
MCR 75,6 MW 75,6 MW 0.0% 100,8 MW 97,0 MW 3.8% 63,0 MW 62,4 M 1.0%
NCre
w1,475 1,369 7.7% 2,706 2,394 13% 1,527 1,651 7.5%
CC $859 million $808
million
6.3% $1,395
million
$1,354
million
3.0% $842 million $840
million
0.2%
Note. This analysis was conducted for Carnival Dream, Oasis of the Seas, and Norwegian Breakaway Parent
Cruise Ships. The highlighted columns in the table show the percentage error between the actual and estimated
values.
As Table 30 shows, the estimates and actual values regarding the parent yacht listed in
the table are relatively close to their values (i.e. < 9% error). For example, the percentage error
between the estimate and the actual MCR of each parent yacht analyzed is no greater than the
4% error. In addition, a comparison of the estimated and actual CC values shows an error of no
more than 7% error.
Table 31 shows the actual and ideal cabin arrangements with the associated NPV for the
mother yacht listed in Table 30. The actual cabin is the one that the ship actually owns. On the
other hand, the ideal cabin arrangement is the one that is expected to show the largest NPV (i.e.
the most profitable). When estimating the NPV regarding this cabin arrangement, the actual
speed characteristics, NPassenger, the combination of EP&B design features, BTicket
values, and cabin volume of each parent yacht are used.
Table 31
Comparison of Actual and Ideal Cabin Arrangements of an Aircraft Carrier
% LLS % MLS % HLS NPV
Afternoon Boat:
Mimpi karnaval
Current 51% 46% 3% -$361 million
Ideal 0% 100% 0% -$264 million
Afternoon Boat:
Oasis Loud
Current 28% 65% 7% $1,911 million
Ideal 0% 100% 0% $2,136 million
Afternoon Boat:
Norwegian Partition
Current 32% 51% 17% $844 million
Ideal 2% 98% 0% $869 million
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As shown by Table 31, the ideal cabin setup is 0% LLS, 100% MLS, and 0% HLS for
Carnival Dream and Oasis of the Seas where NPV is -$264 M and
$2.136 million. Norwegian Breakaway has slightly different ideal cabin arrangements of 2%
LLS, 98% MLS, and 0% HLS with an NPV of $869 M. This mother yacht has a different cabin
arrangement that shows the largest NPV than the Cruise Design, A, B, C, and D. This is largely
due to the difference in cabin volume and ticket prices between this mother yacht and the yacht
design. Nonetheless, the cabin volume and ticket prices of yacht designs are based on statistical
data.
A cabin arrangement consisting of all (or most) of the MLS is considered the most
advantageous cabin arrangement of the mother yacht listed in Table 30. As stated, MLS is
considered to have a companion balcony (e.g. a normal-sized balcony cabin); thus, the MLS
cannot be an interior cabin. This idea can make one wonder if it is practical for a yacht to own
all (or most) of the MLS.
Usually, cruise ships will have a specific deck that is mostly allocated for passenger
accommodation due to noise, logistics, and other reasons. For a typical GT larger yacht, the
beams are wide enough that they have four rows (i.e. in the longitudinal direction) of cabins
along two aisles. This means that two rows of exterior cabins (e.g. balcony cabins) are located on
the outside of the aisle while two rows of interior cabins are located on the inside of the aisle. So,
if a traditional yacht design does not have an interior cabin, it will have a usable volume on this
deck that will not be used and is not suitable for other functions. Nonetheless, there is a
revolutionary yacht superstructure design concept that can be used to have a larger percentage of
balcony cabins (i.e. MLS and/or HLS).
By dividing the yacht's superstructure into two parts (i.e. the port and right
superstructure), four rows of balcony cabins along the two aisles can be achieved. Since this
design concept is used in the hope of increasing passenger ticket revenue, the inner balcony
cabin (i.e. the courtyard balcony cabin) needs to be spaced sufficiently transversely in such a
way that it has an aesthetically pleasing view that guarantees an increase in ticket prices
compared to LLS. This design concept would result in a yacht with a relatively wide beam (i.e.
known as a super-wide yacht). The Oasis of the Seas yacht built is a real-life example of this
design concept, as shown in Figure 33. The yacht has an astonishing 47 m large beam which is
at least 5 m larger than other parent yachts (see Table 1).
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Figure 33. The separate superstructure of the Oasis of the Seas. Adapted from Royal Caribbean International,
2014, Retrieved from www.royalcaribbean.com/findacruise/ships/class/ship/home.do?shipCode=OA.
One consideration that may limit the number of balcony cabins (i.e. MLS or HLS) that a
yacht can have is that a yacht can only have a balcony cabin in its superstructure; However,
usually all passenger cabins are in superstructures. In addition, the hull of the yacht must be
waterproof to a heel angle of 40º. Obviously, the balcony cabin is not waterproof.
Carnival Dream has a negative NPV on Table 31 for the actual and ideal cabin setup.
This idea does not indicate that the revenue of this yacht will not exceed its cost after its service
life (assumed 30 years), but rather that it is not considered profitable with a rate of return of
10%. However, at a rate of return of 6.5% the vessel was analyzed as a neutral investment and at
0%, a profitable investment with an NPV of $1,207 M.
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Chapter 7 – Conclusion
Summary
The implications of the selection of certain design features at the initial design stage
on the profitability potential of the yacht are evaluated in this thesis. Also, a collection of
special design features that promote the most profitable yacht designs is analyzed.
Profitability is analyzed in terms of net present value.
Research and Utilization Approach
The profitability potential of the initial yacht design with various sets of design features
was analyzed using the NPV model. The design of a yacht is considered a profitable investment
if its NPV is greater than zero for the rate of return and the operating life of the ship is 10% and
30 years, respectively. The larger the NPV, the more favorable the perceived yacht design.
The design of a cruise ship is determined by its passenger carrying capacity with double
occupancy. A design feature set is defined as a specific synthesis of design features. Design
features are considered to be limited design decisions that will affect the physical and/or
performance of the yacht in some aspects. The main design features considered are the
arrangement of the cabin space, the type of engine, the propulsion and maneuvering system, and
the criteria for a round bow. Cabin arrangement is defined as the percentage of each cabin type
relative to all yacht cabins. The cabin types under consideration are LLS, MLS, and HLS, having
increasingly greater luxury (i.e. more amenities and greater volume) in that order. The type of
engine considered in this thesis is a diesel and gas turbine engine with varying power output.
Also, the propulsion and maneuvering system is considered traditional and pod.
To estimate the NPV of the yacht design in this thesis, the physical characteristics and
performance of the yacht design are estimated using the techniques discussed in Chapters 3 and
4. Some techniques involve the use of statistics from yachts being built. The yacht is referred to
as the master yacht and consists of 21 different class yachts from 12 different cruise lines. This
statistical data through the mother yacht is not the only way used in this thesis to estimate the
physical characteristics and performance of the yacht design. For example, the residual
resistance of a yacht design is estimated using the model data provided in the publication Ship
Resistance – The Effect of Shape and Key Dimensions (Guldhammer & Harvald, 1974). All of
the physical and performance estimation techniques discussed in this thesis are used and
exhibited in the Cruise Ship Analysis Tool which is then used to analyze the profitability of the
initial yacht design.
CSAT is a clear, concise, and user-friendly interface built on Microsoft Excel. An Excel
workbook consists of three Excel spreadsheets. CSAT (Parameter Estimation)
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The spreadsheet deals with the estimation of yacht design parameters. The CSAT (Cost Analysis)
spreadsheet deals with the estimation of the cost of yacht design. CSAT (Miscellaneous Data)
spreadsheets deal with miscellaneous data that is required to support the algorithms of the other two
spreadsheets.
Using CSAT, NPV as a function of the yacht's design feature set is plotted on the surface
and the design feature set shows the largest NPV estimated. This set of design features is
considered the most profitable and will likely be the most profitable set of design features if
yacht design is implemented. The NPV of the most advantageous set of design features of each
yacht design was analyzed against each other to analyze the implications of yacht
NPassengers on NPV.
Key findings and warnings
NPV characteristics are analyzed for yacht design from various sets of design features.
Each yacht design is distinguished by its NPassengers where Cruise Designs A, B, C, and
D have 750, 1500, 3000, and 4500 passengers, respectively. This range of NPassengers is
chosen in such a way that it covers most of the yachts built. When analyzing NPV for yacht
design, the variables listed in Tables 3, 13, and 18 are assumed.
For each yacht design, the EP&B design features a combination consisting of a diesel
engine, a propulsion system and a pod maneuver, and a rounded bow (i.e. 1.2.1) indicates the
largest NPV for a particular cabin arrangement. The largest NPV of Cruise Ship Design A, B,
C, and D is -$177.5 M, -$53.7 M, $155.5 M, and $388.7 M, respectively. This is because as
NPassenger increases, BTotal will increase more than CTotal. This idea seems to
indicate a very large yacht design in case the GT will show the largest NPV, therefore, being the
most profitable design. This idea is clearly unrealistic. As NPassengers increase, GT
increases as it correlates with VSt. As GT increases, so does BWL, LPP, T, ∇, and other
physical parameters of the ship. By increasing these parameters, ships will be less able to transit
through certain waterways.
Given the assumptions in Tables 3, 13, and 18, NPV is negatively analyzed for each set
of design features of Yacht Design A and B. In fact, yacht design is considered to require 2,086
passenger NPassengers to be considered a neutral investment.
Nonetheless, the yachts built have NPassengers similar to the Yacht Designs A and B are
known to be advantageous. This idea suggests that at least one of the variables assumed in this
table needs to be varied in order for the yacht design to be considered profitable. The speed of
vService and vTrial needs to be reduced by at least 19% and 17% respectively for Yacht
Design A to be considered a neutral investment. On the other hand, a reduction of at least 8%
and 6% in vService and vTrial is necessary for Cruise Design B to be considered a neutral
investment. BTcricket per passenger per day needs to be increased by at least 40% or 33% for
MLS or HLS respectively for Yacht A Design to be considered a neutral investment.
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In addition, the BTcricket per passenger per day LLS must be larger than the MLS for this
design to be considered a neutral investment. This is considered absurd. On the other hand, the
BTcchets B Yacht Design per passenger per day for LLS, MLS, or HLS need to be
increased by at least 7%, 12%, or 13% respectively for this design to be considered a neutral
investment. With regard to the volume of the cabin cabin, the volume of LLS or HLS needs to
be reduced by at least 43% or 32% respectively for Yacht Design A to be considered a neutral
investment. Since the volume of this LLS (i.e. 23,044 m3) is smaller than the volume of the
aircraft carrier's cabin, this reduction is considered unreasonable. The LLS, MLS, or HLS
volume of Yacht Design B must be lowered by at least 12%, 15%, or 12% respectively for this
design to be considered a neutral investment.
The EP&B design features a combination of diesel engines, propulsion systems and pod
maneuvers, and a rounded bow is analyzed as the most advantageous combination for a given
cabin setup, regardless of NPassengers. This is true for diesel engines due to their lower
SFR than gas turbine engines. This is true for propulsion and pod maneuvering systems due to
the reduction in RT (i.e. lower S) when compared to traditional propulsion and maneuvering
systems. This is true for rounded bows because the bulb reduces the RR more than it increases
the RF (i.e. because the bulb increases S) for any yacht design.
Although, the EP&B design featured a combination of diesel engines, pod propulsion
systems and maneuvers, and the rounded bow was established as the most advantageous
combination for all yacht designs, there are caveats to this idea. With regard to the type of
engine, a gas turbine engine can be considered preferable if an engine with a larger power-to-
weight ratio is required. With regards to propulsion and maneuvering systems, some boat
designers may prefer traditional designs due to historical reliability issues with pod designs. This
idea is very important in the shipping industry because these reliability issues can dry out cruise
ships resulting in the ship being unable to generate revenue for some time. Nonetheless, the
reliability of pod designs has improved over time.
The cabin setup that exhibits the greatest NPV (i.e. for the EP&B 1.2.1 design feature
combination) is estimated at 88% LLS, 6% MLS, and 6% HLS for Yacht Design A. This is
because these design features have the characteristics of RT and BTicket assemblies where
low RTs are conducive to high NPVs, especially at lower NPassengers. The
reason why this design feature set shows the lowest NPV over the one with the lowest RT (i.e.
82% LLS, 16% MLS, and 2% HLS cabin setups have an RT of 903.6 kN) is because the
difference in BTicket, Life ($8 M) is greater than the difference in CFuel, Life
(i.e. < $1 million). The cabin settings that show the largest NPV for Yacht Designs B, C, and D
are 100% LLS, 0% MLS, and 0% HLS. This shows the least luxurious cabin arrangement is the
most favorable for the design of this yacht. In fact, on NPassengers with more than 854
passengers, this cabin arrangement will always show the largest NPV. This trend occurs because
the gains from the additional revenue generated through the selection of more luxurious cabin
arrangements are offset by losses from increased construction and
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Operational costs as NPassengers increased. In more detail, the BTicket-to-GT
dependent cost ratio (i.e. CC, CFuel, CP&R, CFood, and COSO) decreased as
the luxury of cabin settings increased
As stated, when analyzing NPV, the variables listed in Tables 3, 13, and 18 are assumed
to be corrected for the analyzed yacht design. Fixing these variables can affect the cabin setup
which shows the largest NPV of the yacht design. For example, an increase of just $1.85 in
Btiket LLS Tickets per passenger per day shows the most favorable cabin setup from A.1.2.1
changing from 88% LLS, 6% MLS, and 6% HLS to 90% LLS, 2% MLS, and 8% HLS. In
addition, an increase of just 0.011 m3 in LLS cabin volume shows the most favorable cabin
setup from A.1.2.1 changed to 82% LLS, 16% MLS and 2% HLS. Thus, the most favorable
cabin arrangements are clearly sensitive to fluctuations in ticket prices and the volume of cabin
types. Nonetheless, the ticket prices and cabin type volumes analyzed are based on statistical
data.
Possible Future Research
This thesis analyzes the implications of certain initial design feature decisions on the
potential profitability of yacht designs. It is mainly analyzed with respect to the cabin space
arrangement, engine type, propulsion and maneuvering systems, and round arc criteria. Possible
future research may include consideration of more design features.
Perhaps, the implications of the gastric decision can be analyzed more thoroughly.
The design of NPassengers yachts between 750 and 4,500 passengers was analyzed.
This is partly due to the fact that most cruise ships have NPassenger in range. Another
reason is due to the limitations and caveats of the methods of Guldhammer and Harvald (1974)
used to estimate the CR of yacht design. First, this CR diagram applies to Fn between 0.15
and 0.45. At Fn greater than about 0.30, this diagram is considered somewhat unreliable for
hulls different from the models used in the pull-up test because slight variations in hulls can
greatly affect CR values. Due to the constant velocity at 22.5 kts and 21.0 kts respectively for
vTrial and vService, analyzing a yacht design with a lower NPassengers than a Yacht
Design A can result in an inaccurate CR estimate due to the higher Fon. So, one future
recommendation is to consider using other methods to predict CR for yacht designs with
lower NPassengers than those analyzed in this thesis.
It is assumed that passengers' shipping-related spending habits are based on their annual
income. It is based on research by the International Association of Cruise Lines (2011).
Nonetheless, the BO&O of passengers may be sensitive to the type of cabin in which the
passenger is staying. It will be an interesting future study to analyze this idea.
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The sensitivity of the most favorable cabin settings to ticket prices or volume
fluctuations of different cabin types is analyzed. An interesting future study may be to analyze
the implications of these fluctuations on consumer demand.
Signifikansi Facility
This thesis provides a means to evaluate the implications that a particular initial design
feature decision can have on the yacht's potential profitability. This is achieved by using the net
present value (NPV) model and the physical and performance estimation techniques discussed in
this thesis. These techniques (and NPV models) are showcased in the Cruise Ship Analysis Tool
(CSAT) which provides a clear, concise, and user-friendly interface for analyzing the
profitability of early yacht designs.
This thesis then analyzes the implications that various design features have on the
profitability of yachts and determines the specific set of design features of these design features
that indicate the greatest profitability for different yacht designs. Furthermore, this thesis
analyzes the implications that vary in speed, passenger carrying capacity, price or volume of
cabin tickets on the potential profitability of cruise ships. This thesis is not only short-sighted
towards cost analysis where initial stability is also analyzed for yacht design. This analysis
shows that the yacht design passed the initial metacentric altitude stability criteria set out in
IMO Resolution A.749 (1993)
The author believes that the techniques discussed in this thesis can be used by ship
designers to provide more profitable designs for their customers. This can be achieved quickly
and reasonably with CSAT. It is also believed that the utilization of these techniques and CSAT
provides ship designers with a viable means of analyzing the consequences that an initial ship
design decision can have over the life of the vessel. In addition, the CSAT can serve as a
measure of its own estimation techniques.
