Mathematical Problems on Aircraft De-icing Technologies and Methods
1. If a de-icing truck can spray 500 liters of fluid per minute, how many liters will it spray in 15
minutes?
a) 5000 b) 6500 c) 7500 d) 8000
Answer: c) 7500
2. An aircraft has a wing surface area of 120 m². If 1 liter of de-icing fluid covers 4 m², how many
liters are needed to cover both wings?
a) 30 b) 60 c) 90 d) 120
Answer: b) 60
3. De-icing fluid costs $5 per liter. If an airline uses 2000 liters per day for 30 days, what is the total
cost?
a) $250,000 b) $300,000 c) $350,000 d) $400,000
Answer: b) $300,000
4. A heated hangar can accommodate 5 small aircraft or 2 large aircraft. If there are 15 small aircraft
and 6 large aircraft to be de-iced, how many cycles will it take?
a) 5 b) 6 c) 7 d) 8
Answer: b) 6
5. If the temperature of de-icing fluid needs to be maintained at 60°C and it cools at a rate of 2°C per
minute, how long will it take to reach 40°C?
a) 5 minutes b) 10 minutes c) 15 minutes d) 20 minutes
Answer: b) 10 minutes
6. An infrared de-icing system can heat 1 m² of aircraft surface by 10°C in 30 seconds. How long will it
take to heat 50 m² by 20°C?
a) 25 minutes b) 50 minutes c) 75 minutes d) 100 minutes
Answer: b) 50 minutes
7. A de-icing truck has a tank capacity of 2000 liters. If it uses 75% of its capacity for each aircraft,
how many aircraft can it de-ice before refilling?
a) 1 b) 2 c) 3 d) 4
Answer: b) 2
8. If a glycol-based de-icing fluid is diluted to 40% concentration, how many liters of pure glycol are
needed to make 500 liters of the solution?
a) 150 liters b) 200 liters c) 250 liters d) 300 liters
Answer: b) 200 liters
9. An electro-expulsive de-icing system uses 1000 watts of power per square meter. If an aircraft has
80 m² of surface to be de-iced, what is the total power consumption?
a) 60 kW b) 70 kW c) 80 kW d) 90 kW
Answer: c) 80 kW
10. A de-icing operation takes 20 minutes per aircraft. If there are 12 aircraft to be de-iced and 3 de-
icing trucks available, how long will the entire operation take?
a) 60 minutes b) 80 minutes c) 100 minutes d) 120 minutes
Answer: b) 80 minutes
11. If a de-icing fluid mixture is 20% glycol and 80% water, how many liters of glycol are in a 350-liter
mixture?
a) 50 liters b) 60 liters c) 70 liters d) 80 liters
Answer: c) 70 liters
12. An aircraft's anti-icing system can prevent ice formation for 3 hours. If a flight duration is 7.5
hours, how many times does the system need to be activated?
a) 2 times b) 3 times c) 4 times d) 5 times
Answer: b) 3 times
13. A de-icing pad can accommodate 4 aircraft simultaneously. If 30 aircraft need de-icing and each
operation takes 15 minutes, how long will the entire process take?
a) 1 hour 45 minutes b) 1 hour 52.5 minutes c) 2 hours d) 2 hours 15 minutes
Answer: b) 1 hour 52.5 minutes
14. If a pneumatic de-icing boot inflates and deflates 3 times per minute, how many cycles will it
complete in a 2-hour flight?
a) 320 b) 340 c) 360 d) 380
Answer: c) 360
15. An electric heating element uses 500 watts per meter of length. If an aircraft's leading edge is 30
meters long and requires heating on both sides, what is the total power consumption?
a) 15 kW b) 20 kW c) 25 kW d) 30 kW
Answer: d) 30 kW
16. A de-icing fluid sprayer covers 2 m²/second. How long will it take to cover an aircraft with a total
surface area of 300 m²?
a) 120 seconds b) 140 seconds c) 150 seconds d) 160 seconds
Answer: c) 150 seconds
17. If the freezing point of a 50% glycol solution is -34°C, and it increases by 1°C for every 1%
decrease in concentration, what is the freezing point of a 40% solution?
a) -24°C b) -26°C c) -28°C d) -30°C
Answer: a) -24°C
18. An airport uses 50,000 liters of de-icing fluid per month. If they switch to a new system that
reduces consumption by 15%, how many liters will they save in a year?
a) 75,000 b) 80,000 c) 85,000 d) 90,000
Answer: d) 90,000
19. If a de-icing truck can hold 3000 liters and uses 200 liters per aircraft, how many aircraft can it
service before needing a refill?
a) 12 b) 13 c) 14 d) 15
Answer: d) 15
20. An infrared de-icing system uses 300 kW of power and can de-ice an aircraft in 6 minutes. How
much energy (in kWh) does it consume per aircraft?
a) 20 kWh b) 25 kWh c) 30 kWh d) 35 kWh
Answer: c) 30 kWh
21. If a de-icing fluid has a specific gravity of 1.1 and a 55-gallon drum is filled to 80% capacity, what
is the weight of the fluid in kilograms? (1 gallon ≈ 3.78541 liters)
a) 182 kg b) 192 kg c) 202 kg d) 212 kg
Answer: b) 192 kg
22. An airline spends $500,000 on de-icing fluid annually. If they invest in a new system that costs
$2,000,000 but reduces fluid consumption by 30%, how many years will it take for the investment to
break even?
a) 12 years b) 13 years c) 14 years d) 15 years
Answer: b) 13 years
23. If an electrothermal de-icing system heats the surface at a rate of 5°C per minute and needs to
raise the temperature from -10°C to 20°C, how long will it take?
a) 4 minutes b) 5 minutes c) 6 minutes d) 7 minutes
Answer: c) 6 minutes
24. A de-icing pad can handle 1 wide-body or 2 narrow-body aircraft at a time. If there are 5 wide-
body and 8 narrow-body aircraft to be de-iced, what's the minimum number of cycles needed?
a) 7 b) 8 c) 9 d) 10
Answer: c) 9
25. If a de-icing operation uses 1.5 liters of fluid per square meter of aircraft surface, how many
square meters can be treated with a 1000-liter tank?
a) 600 m² b) 650 m² c) 666 m² d) 700 m²
Answer: c) 666 m²
26. An airport handles 200 flights per day in winter. If 75% of these flights require de-icing and each
operation uses 400 liters of fluid, how many liters are used daily?
a) 55,000 b) 60,000 c) 65,000 d) 70,000
Answer: b) 60,000
27. If the viscosity of de-icing fluid increases by 5% for every 1°C drop in temperature, what is the
percentage increase in viscosity when the temperature drops from 0°C to -8°C?
a) 35% b) 40% c) 45% d) 50%
Answer: b) 40%
28. A de-icing truck pumps fluid at a rate of 40 gallons per minute. How many minutes will it take to
empty a 1500-gallon tank?
a) 35.5 minutes b) 37.5 minutes c) 39.5 minutes d) 41.5 minutes
Answer: b) 37.5 minutes
29. If a heated hangar can raise the temperature of an aircraft by 2°C every 5 minutes, how long will
it take to raise the temperature from -15°C to 5°C?
a) 40 minutes b) 45 minutes c) 50 minutes d) 55 minutes
Answer: c) 50 minutes
30. An airline uses 3 different de-icing fluid mixtures: 20%, 40%, and 60% glycol. If they use 1000
liters of each, what is the total amount of pure glycol used?
a) 1000 liters b) 1100 liters c) 1200 liters d) 1300 liters
Answer: c) 1200 liters
31. If a de-icing pad can process 1 aircraft every 12 minutes, how many aircraft can it handle in an 8-
hour shift, assuming no breaks?
a) 38 b) 39 c) 40 d) 41
Answer: c) 40
32. A new de-icing technology claims to reduce fluid usage by 25%. If an airport currently uses
80,000 liters per month, how much will they use with the new technology?
a) 55,000 liters b) 60,000 liters c) 65,000 liters d) 70,000 liters
Answer: b) 60,000 liters
33. If the freezing point of pure water is 0°C and a 50% glycol solution freezes at -34°C, what is the
approximate freezing point of a 25% glycol solution?
a) -14°C b) -16°C c) -17°C d) -19°C
Answer: c) -17°C
34. An aircraft has a wing span of 40 meters and a chord length of 5 meters. If de-icing fluid is applied
at 0.5 liters per square meter, how many liters are needed for both wings?
a) 180 liters b) 190 liters c) 200 liters d) 210 liters
Answer: c) 200 liters
35. If a de-icing operation costs $500 per aircraft and an airline performs this operation on 30% of its
200 daily flights during winter, what is the daily cost?
a) $28,000 b) $29,000 c) $30,000 d) $31,000
Answer: c) $30,000
36. A pneumatic de-icing boot inflates to 3 cm thickness. If it covers a wing section that is 10 meters
long and 1 meter wide, what volume of air is needed to inflate it?
a) 0.25 m³ b) 0.3 m³ c) 0.35 m³ d) 0.4 m³
Answer: b) 0.3 m³
37. If an electrochemical de-icing system uses 2 amps of current per square meter at 24 volts, what is
the power consumption for a 50 m² surface?
a) 2000 watts b) 2200 watts c) 2400 watts d) 2600 watts
Answer: c) 2400 watts
38. A de-icing fluid mixture is 30% glycol by volume. How many liters of glycol should be added to
700 liters of this mixture to increase the concentration to 40%?
a) 100 liters b) 110 liters c) 120 liters d) 130 liters
Answer: c) 120 liters
39. If a de-icing truck can service an aircraft in 15 minutes and spends 5 minutes moving between
aircraft, how many aircraft can it service in 2 hours?
a) 5 b) 6 c) 7 d) 8
Answer: b) 6
40. An airport uses 1.5 million liters of de-icing fluid annually. If the fluid costs $2 per liter and they
implement a recycling system that recovers 40% of the fluid, how much money will they save per
year?
a) $1,100,000 b) $1,150,000 c) $1,200,000 d) $1,250,000
Answer: c) $1,200,000
41. If an infrared de-icing system uses 250 kW of power and operates for 8 hours a day, 120 days per
year, how many megawatt-hours (MWh) of energy does it consume annually?
a) 220 MWh b) 230 MWh c) 240 MWh d) 250 MWh
Answer: c) 240 MWh
42. A de-icing fluid sprayer covers an area of 3 m²/second. If an aircraft has a total surface area of 450
m² and 80% needs to be sprayed, how long will the operation take?
a) 110 seconds b) 120 seconds c) 130 seconds d) 140 seconds
Answer: b) 120 seconds
43. If the density of a de-icing fluid is 1.05 g/cm³, what is the mass of fluid in a 200-liter tank?
a) 200 kg b) 205 kg c) 210 kg d) 215 kg
Answer: c) 210 kg
44. An airline uses 100,000 liters of de-icing fluid per month at a cost of $3 per liter. If they switch to
a more expensive fluid that costs $4 per liter but reduces consumption by 20%, what is their monthly
savings?
a) $20,000 b) $30,000 c) $40,000 d) $50,000
Answer: c) $40,000
45. If a de-icing pad can handle 3 narrow-body or 1 wide-body aircraft at a time, and it takes 20
minutes to de-ice a narrow-body and 40 minutes for a wide-body, how long will it take to de-ice 9
narrow-body and 3 wide-body aircraft?
a) 140 minutes b) 160 minutes c) 180 minutes d) 200 minutes
Answer: b) 160 minutes
A de-icing operation takes 20 minutes per aircraft. If there are 12 aircraft to be de-iced and 3 de-icing
trucks available, how long will the entire operation take?
a) 60 minutes b) 80 minutes c) 100 minutes d) 120 minutes
Answer: b) 80 minutes
11. If a de-icing fluid mixture is 20% glycol and 80% water, how many liters of glycol are in a 350-liter
mixture?
a) 50 liters b) 60 liters c) 70 liters d) 80 liters
Answer: c) 70 liters
12. An aircraft's anti-icing system can prevent ice formation for 3 hours. If a flight duration is 7.5
hours, how many times does the system need to be activated?
a) 2 times b) 3 times c) 4 times d) 5 times
Answer: b) 3 times
13. A de-icing pad can accommodate 4 aircraft simultaneously. If 30 aircraft need de-icing and each
operation takes 15 minutes, how long will the entire process take?
a) 1 hour 45 minutes b) 1 hour 52.5 minutes c) 2 hours d) 2 hours 15 minutes
Answer: b) 1 hour 52.5 minutes
14. If a pneumatic de-icing boot inflates and deflates 3 times per minute, how many cycles will it
complete in a 2-hour flight?
a) 320 b) 340 c) 360 d) 380
Answer: c) 360
15. An electric heating element uses 500 watts per meter of length. If an aircraft's leading edge is 30
meters long and requires heating on both sides, what is the total power consumption?
a) 15 kW b) 20 kW c) 25 kW d) 30 kW
Answer: d) 30 kW
16. A de-icing fluid sprayer covers 2 m²/second. How long will it take to cover an aircraft with a total
surface area of 300 m²?
a) 120 seconds b) 140 seconds c) 150 seconds d) 160 seconds
Answer: c) 150 seconds
17. If the freezing point of a 50% glycol solution is -34°C, and it increases by 1°C for every 1%
decrease in concentration, what is the freezing point of a 40% solution?
a) -24°C b) -26°C c) -28°C d) -30°C
Answer: a) -24°C
18. An airport uses 50,000 liters of de-icing fluid per month. If they switch to a new system that
reduces consumption by 15%, how many liters will they save in a year?
a) 75,000 b) 80,000 c) 85,000 d) 90,000
Answer: d) 90,000
19. If a de-icing truck can hold 3000 liters and uses 200 liters per aircraft, how many aircraft can it
service before needing a refill?
a) 12 b) 13 c) 14 d) 15
Answer: d) 15
20. An infrared de-icing system uses 300 kW of power and can de-ice an aircraft in 6 minutes. How
much energy (in kWh) does it consume per aircraft?
a) 20 kWh b) 25 kWh c) 30 kWh d) 35 kWh
Answer: c) 30 kWh
21. If a de-icing fluid has a specific gravity of 1.1 and a 55-gallon drum is filled to 80% capacity, what
is the weight of the fluid in kilograms? (1 gallon ≈ 3.78541 liters)
a) 182 kg b) 192 kg c) 202 kg d) 212 kg
Answer: b) 192 kg
22. An airline spends $500,000 on de-icing fluid annually. If they invest in a new system that costs
$2,000,000 but reduces fluid consumption by 30%, how many years will it take for the investment to
break even?
a) 12 years b) 13 years c) 14 years d) 15 years
Answer: b) 13 years
23. If an electrothermal de-icing system heats the surface at a rate of 5°C per minute and needs to
raise the temperature from -10°C to 20°C, how long will it take?
a) 4 minutes b) 5 minutes c) 6 minutes d) 7 minutes
Answer: c) 6 minutes
24. A de-icing pad can handle 1 wide-body or 2 narrow-body aircraft at a time. If there are 5 wide-
body and 8 narrow-body aircraft to be de-iced, what's the minimum number of cycles needed?
a) 7 b) 8 c) 9 d) 10
Answer: c) 9
25. If a de-icing operation uses 1.5 liters of fluid per square meter of aircraft surface, how many
square meters can be treated with a 1000-liter tank?
a) 600 m² b) 650 m² c) 666 m² d) 700 m²
Answer: c) 666 m²
26. An airport handles 200 flights per day in winter. If 75% of these flights require de-icing and each
operation uses 400 liters of fluid, how many liters are used daily?
a) 55,000 b) 60,000 c) 65,000 d) 70,000
Answer: b) 60,000
27. If the viscosity of de-icing fluid increases by 5% for every 1°C drop in temperature, what is the
percentage increase in viscosity when the temperature drops from 0°C to -8°C?
a) 35% b) 40% c) 45% d) 50%
Answer: b) 40%
28. A de-icing truck pumps fluid at a rate of 40 gallons per minute. How many minutes will it take to
empty a 1500-gallon tank?
a) 35.5 minutes b) 37.5 minutes c) 39.5 minutes d) 41.5 minutes
Answer: b) 37.5 minutes
29. If a heated hangar can raise the temperature of an aircraft by 2°C every 5 minutes, how long will
it take to raise the temperature from -15°C to 5°C?
a) 40 minutes b) 45 minutes c) 50 minutes d) 55 minutes
Answer: c) 50 minutes
30. An airline uses 3 different de-icing fluid mixtures: 20%, 40%, and 60% glycol. If they use 1000
liters of each, what is the total amount of pure glycol used?
a) 1000 liters b) 1100 liters c) 1200 liters d) 1300 liters
Answer: c) 1200 liters
31. If a de-icing pad can process 1 aircraft every 12 minutes, how many aircraft can it handle in an 8-
hour shift, assuming no breaks?
a) 38 b) 39 c) 40 d) 41
Answer: c) 40
32. A new de-icing technology claims to reduce fluid usage by 25%. If an airport currently uses
80,000 liters per month, how much will they use with the new technology?
a) 55,000 liters b) 60,000 liters c) 65,000 liters d) 70,000 liters
Answer: b) 60,000 liters
33. If the freezing point of pure water is 0°C and a 50% glycol solution freezes at -34°C, what is the
approximate freezing point of a 25% glycol solution?
a) -14°C b) -16°C c) -17°C d) -19°C
Answer: c) -17°C
34. An aircraft has a wing span of 40 meters and a chord length of 5 meters. If de-icing fluid is applied
at 0.5 liters per square meter, how many liters are needed for both wings?
a) 180 liters b) 190 liters c) 200 liters d) 210 liters
Answer: c) 200 liters
35. If a de-icing operation costs $500 per aircraft and an airline performs this operation on 30% of its
200 daily flights during winter, what is the daily cost?
a) $28,000 b) $29,000 c) $30,000 d) $31,000
Answer: c) $30,000
36. A pneumatic de-icing boot inflates to 3 cm thickness. If it covers a wing section that is 10 meters
long and 1 meter wide, what volume of air is needed to inflate it?
a) 0.25 m³ b) 0.3 m³ c) 0.35 m³ d) 0.4 m³
Answer: b) 0.3 m³
37. If an electrochemical de-icing system uses 2 amps of current per square meter at 24 volts, what is
the power consumption for a 50 m² surface?
a) 2000 watts b) 2200 watts c) 2400 watts d) 2600 watts
Answer: c) 2400 watts
38. A de-icing fluid mixture is 30% glycol by volume. How many liters of glycol should be added to
700 liters of this mixture to increase the concentration to 40%?
a) 100 liters b) 110 liters c) 120 liters d) 130 liters
Answer: c) 120 liters
39. If a de-icing truck can service an aircraft in 15 minutes and spends 5 minutes moving between
aircraft, how many aircraft can it service in 2 hours?
a) 5 b) 6 c) 7 d) 8
Answer: b) 6
40. An airport uses 1.5 million liters of de-icing fluid annually. If the fluid costs $2 per liter and they
implement a recycling system that recovers 40% of the fluid, how much money will they save per
year?
a) $1,100,000 b) $1,150,000 c) $1,200,000 d) $1,250,000
Answer: c) $1,200,000
41. If an infrared de-icing system uses 250 kW of power and operates for 8 hours a day, 120 days per
year, how many megawatt-hours (MWh) of energy does it consume annually?
a) 220 MWh b) 230 MWh c) 240 MWh d) 250 MWh
Answer: c) 240 MWh
42. A de-icing fluid sprayer covers an area of 3 m²/second. If an aircraft has a total surface area of 450
m² and 80% needs to be sprayed, how long will the operation take?
a) 110 seconds b) 120 seconds c) 130 seconds d) 140 seconds
Answer: b) 120 seconds
43. If the density of a de-icing fluid is 1.05 g/cm³, what is the mass of fluid in a 200-liter tank?
a) 200 kg b) 205 kg c) 210 kg d) 215 kg
Answer: c) 210 kg
44. An airline uses 100,000 liters of de-icing fluid per month at a cost of $3 per liter. If they switch to
a more expensive fluid that costs $4 per liter but reduces consumption by 20%, what is their monthly
savings?
a) $20,000 b) $30,000 c) $40,000 d) $50,000
Answer: c) $40,000
45. If a de-icing pad can handle 3 narrow-body or 1 wide-body aircraft at a time, and it takes 20
minutes to de-ice a narrow-body and 40 minutes for a wide-body, how long will it take to de-ice 9
narrow-body and 3 wide-body aircraft?
a) 140 minutes b) 160 minutes c) 180 minutes d) 200 minutes
Answer: b) 160 minutes
A de-icing operation takes 20 minutes per aircraft. If there are 12 aircraft to be de-iced and 3 de-icing
trucks available, how long will the entire operation take?
a) 60 minutes b) 80 minutes c) 100 minutes d) 120 minutes
Answer: b) 80 minutes
11. If a de-icing fluid mixture is 20% glycol and 80% water, how many liters of glycol are in a 350-liter
mixture?
a) 50 liters b) 60 liters c) 70 liters d) 80 liters
Answer: c) 70 liters
12. An aircraft's anti-icing system can prevent ice formation for 3 hours. If a flight duration is 7.5
hours, how many times does the system need to be activated?
a) 2 times b) 3 times c) 4 times d) 5 times
Answer: b) 3 times
13. A de-icing pad can accommodate 4 aircraft simultaneously. If 30 aircraft need de-icing and each
operation takes 15 minutes, how long will the entire process take?
a) 1 hour 45 minutes b) 1 hour 52.5 minutes c) 2 hours d) 2 hours 15 minutes
Answer: b) 1 hour 52.5 minutes
14. If a pneumatic de-icing boot inflates and deflates 3 times per minute, how many cycles will it
complete in a 2-hour flight?
a) 320 b) 340 c) 360 d) 380
Answer: c) 360
15. An electric heating element uses 500 watts per meter of length. If an aircraft's leading edge is 30
meters long and requires heating on both sides, what is the total power consumption?
a) 15 kW b) 20 kW c) 25 kW d) 30 kW
Answer: d) 30 kW
16. A de-icing fluid sprayer covers 2 m²/second. How long will it take to cover an aircraft with a total
surface area of 300 m²?
a) 120 seconds b) 140 seconds c) 150 seconds d) 160 seconds
Answer: c) 150 seconds
17. If the freezing point of a 50% glycol solution is -34°C, and it increases by 1°C for every 1%
decrease in concentration, what is the freezing point of a 40% solution?
a) -24°C b) -26°C c) -28°C d) -30°C
Answer: a) -24°C
18. An airport uses 50,000 liters of de-icing fluid per month. If they switch to a new system that
reduces consumption by 15%, how many liters will they save in a year?
a) 75,000 b) 80,000 c) 85,000 d) 90,000
Answer: d) 90,000
19. If a de-icing truck can hold 3000 liters and uses 200 liters per aircraft, how many aircraft can it
service before needing a refill?
a) 12 b) 13 c) 14 d) 15
Answer: d) 15
20. An infrared de-icing system uses 300 kW of power and can de-ice an aircraft in 6 minutes. How
much energy (in kWh) does it consume per aircraft?
a) 20 kWh b) 25 kWh c) 30 kWh d) 35 kWh
Answer: c) 30 kWh
21. If a de-icing fluid has a specific gravity of 1.1 and a 55-gallon drum is filled to 80% capacity, what
is the weight of the fluid in kilograms? (1 gallon ≈ 3.78541 liters)
a) 182 kg b) 192 kg c) 202 kg d) 212 kg
Answer: b) 192 kg
22. An airline spends $500,000 on de-icing fluid annually. If they invest in a new system that costs
$2,000,000 but reduces fluid consumption by 30%, how many years will it take for the investment to
break even?
a) 12 years b) 13 years c) 14 years d) 15 years
Answer: b) 13 years
23. If an electrothermal de-icing system heats the surface at a rate of 5°C per minute and needs to
raise the temperature from -10°C to 20°C, how long will it take?
a) 4 minutes b) 5 minutes c) 6 minutes d) 7 minutes
Answer: c) 6 minutes
24. A de-icing pad can handle 1 wide-body or 2 narrow-body aircraft at a time. If there are 5 wide-
body and 8 narrow-body aircraft to be de-iced, what's the minimum number of cycles needed?
a) 7 b) 8 c) 9 d) 10
Answer: c) 9
25. If a de-icing operation uses 1.5 liters of fluid per square meter of aircraft surface, how many
square meters can be treated with a 1000-liter tank?
a) 600 m² b) 650 m² c) 666 m² d) 700 m²
Answer: c) 666 m²
26. An airport handles 200 flights per day in winter. If 75% of these flights require de-icing and each
operation uses 400 liters of fluid, how many liters are used daily?
a) 55,000 b) 60,000 c) 65,000 d) 70,000
Answer: b) 60,000
27. If the viscosity of de-icing fluid increases by 5% for every 1°C drop in temperature, what is the
percentage increase in viscosity when the temperature drops from 0°C to -8°C?
a) 35% b) 40% c) 45% d) 50%
Answer: b) 40%
28. A de-icing truck pumps fluid at a rate of 40 gallons per minute. How many minutes will it take to
empty a 1500-gallon tank?
a) 35.5 minutes b) 37.5 minutes c) 39.5 minutes d) 41.5 minutes
Answer: b) 37.5 minutes
29. If a heated hangar can raise the temperature of an aircraft by 2°C every 5 minutes, how long will
it take to raise the temperature from -15°C to 5°C?
a) 40 minutes b) 45 minutes c) 50 minutes d) 55 minutes
Answer: c) 50 minutes
30. An airline uses 3 different de-icing fluid mixtures: 20%, 40%, and 60% glycol. If they use 1000
liters of each, what is the total amount of pure glycol used?
a) 1000 liters b) 1100 liters c) 1200 liters d) 1300 liters
Answer: c) 1200 liters
31. If a de-icing pad can process 1 aircraft every 12 minutes, how many aircraft can it handle in an 8-
hour shift, assuming no breaks?
a) 38 b) 39 c) 40 d) 41
Answer: c) 40
32. A new de-icing technology claims to reduce fluid usage by 25%. If an airport currently uses
80,000 liters per month, how much will they use with the new technology?
a) 55,000 liters b) 60,000 liters c) 65,000 liters d) 70,000 liters
Answer: b) 60,000 liters
33. If the freezing point of pure water is 0°C and a 50% glycol solution freezes at -34°C, what is the
approximate freezing point of a 25% glycol solution?
a) -14°C b) -16°C c) -17°C d) -19°C
Answer: c) -17°C
34. An aircraft has a wing span of 40 meters and a chord length of 5 meters. If de-icing fluid is applied
at 0.5 liters per square meter, how many liters are needed for both wings?
a) 180 liters b) 190 liters c) 200 liters d) 210 liters
Answer: c) 200 liters
35. If a de-icing operation costs $500 per aircraft and an airline performs this operation on 30% of its
200 daily flights during winter, what is the daily cost?
a) $28,000 b) $29,000 c) $30,000 d) $31,000
Answer: c) $30,000
36. A pneumatic de-icing boot inflates to 3 cm thickness. If it covers a wing section that is 10 meters
long and 1 meter wide, what volume of air is needed to inflate it?
a) 0.25 m³ b) 0.3 m³ c) 0.35 m³ d) 0.4 m³
Answer: b) 0.3 m³
37. If an electrochemical de-icing system uses 2 amps of current per square meter at 24 volts, what is
the power consumption for a 50 m² surface?
a) 2000 watts b) 2200 watts c) 2400 watts d) 2600 watts
Answer: c) 2400 watts
38. A de-icing fluid mixture is 30% glycol by volume. How many liters of glycol should be added to
700 liters of this mixture to increase the concentration to 40%?
a) 100 liters b) 110 liters c) 120 liters d) 130 liters
Answer: c) 120 liters
39. If a de-icing truck can service an aircraft in 15 minutes and spends 5 minutes moving between
aircraft, how many aircraft can it service in 2 hours?
a) 5 b) 6 c) 7 d) 8
Answer: b) 6
40. An airport uses 1.5 million liters of de-icing fluid annually. If the fluid costs $2 per liter and they
implement a recycling system that recovers 40% of the fluid, how much money will they save per
year?
a) $1,100,000 b) $1,150,000 c) $1,200,000 d) $1,250,000
Answer: c) $1,200,000
41. If an infrared de-icing system uses 250 kW of power and operates for 8 hours a day, 120 days per
year, how many megawatt-hours (MWh) of energy does it consume annually?
a) 220 MWh b) 230 MWh c) 240 MWh d) 250 MWh
Answer: c) 240 MWh
42. A de-icing fluid sprayer covers an area of 3 m²/second. If an aircraft has a total surface area of 450
m² and 80% needs to be sprayed, how long will the operation take?
a) 110 seconds b) 120 seconds c) 130 seconds d) 140 seconds
Answer: b) 120 seconds
43. If the density of a de-icing fluid is 1.05 g/cm³, what is the mass of fluid in a 200-liter tank?
a) 200 kg b) 205 kg c) 210 kg d) 215 kg
Answer: c) 210 kg
44. An airline uses 100,000 liters of de-icing fluid per month at a cost of $3 per liter. If they switch to
a more expensive fluid that costs $4 per liter but reduces consumption by 20%, what is their monthly
savings?
a) $20,000 b) $30,000 c) $40,000 d) $50,000
Answer: c) $40,000
45. If a de-icing pad can handle 3 narrow-body or 1 wide-body aircraft at a time, and it takes 20
minutes to de-ice a narrow-body and 40 minutes for a wide-body, how long will it take to de-ice 9
narrow-body and 3 wide-body aircraft?
a) 140 minutes b) 160 minutes c) 180 minutes d) 200 minutes
Answer: b) 160 minutes
A de-icing operation takes 20 minutes per aircraft. If there are 12 aircraft to be de-iced and 3 de-icing
trucks available, how long will the entire operation take?
a) 60 minutes b) 80 minutes c) 100 minutes d) 120 minutes
Answer: b) 80 minutes
11. If a de-icing fluid mixture is 20% glycol and 80% water, how many liters of glycol are in a 350-liter
mixture?
a) 50 liters b) 60 liters c) 70 liters d) 80 liters
Answer: c) 70 liters
12. An aircraft's anti-icing system can prevent ice formation for 3 hours. If a flight duration is 7.5
hours, how many times does the system need to be activated?
a) 2 times b) 3 times c) 4 times d) 5 times
Answer: b) 3 times
13. A de-icing pad can accommodate 4 aircraft simultaneously. If 30 aircraft need de-icing and each
operation takes 15 minutes, how long will the entire process take?
a) 1 hour 45 minutes b) 1 hour 52.5 minutes c) 2 hours d) 2 hours 15 minutes
Answer: b) 1 hour 52.5 minutes
14. If a pneumatic de-icing boot inflates and deflates 3 times per minute, how many cycles will it
complete in a 2-hour flight?
a) 320 b) 340 c) 360 d) 380
Answer: c) 360
15. An electric heating element uses 500 watts per meter of length. If an aircraft's leading edge is 30
meters long and requires heating on both sides, what is the total power consumption?
a) 15 kW b) 20 kW c) 25 kW d) 30 kW
Answer: d) 30 kW
16. A de-icing fluid sprayer covers 2 m²/second. How long will it take to cover an aircraft with a total
surface area of 300 m²?
a) 120 seconds b) 140 seconds c) 150 seconds d) 160 seconds
Answer: c) 150 seconds
17. If the freezing point of a 50% glycol solution is -34°C, and it increases by 1°C for every 1%
decrease in concentration, what is the freezing point of a 40% solution?
a) -24°C b) -26°C c) -28°C d) -30°C
Answer: a) -24°C
18. An airport uses 50,000 liters of de-icing fluid per month. If they switch to a new system that
reduces consumption by 15%, how many liters will they save in a year?
a) 75,000 b) 80,000 c) 85,000 d) 90,000
Answer: d) 90,000
19. If a de-icing truck can hold 3000 liters and uses 200 liters per aircraft, how many aircraft can it
service before needing a refill?
a) 12 b) 13 c) 14 d) 15
Answer: d) 15
20. An infrared de-icing system uses 300 kW of power and can de-ice an aircraft in 6 minutes. How
much energy (in kWh) does it consume per aircraft?
a) 20 kWh b) 25 kWh c) 30 kWh d) 35 kWh
Answer: c) 30 kWh
21. If a de-icing fluid has a specific gravity of 1.1 and a 55-gallon drum is filled to 80% capacity, what
is the weight of the fluid in kilograms? (1 gallon ≈ 3.78541 liters)
a) 182 kg b) 192 kg c) 202 kg d) 212 kg
Answer: b) 192 kg
22. An airline spends $500,000 on de-icing fluid annually. If they invest in a new system that costs
$2,000,000 but reduces fluid consumption by 30%, how many years will it take for the investment to
break even?
a) 12 years b) 13 years c) 14 years d) 15 years
Answer: b) 13 years
23. If an electrothermal de-icing system heats the surface at a rate of 5°C per minute and needs to
raise the temperature from -10°C to 20°C, how long will it take?
a) 4 minutes b) 5 minutes c) 6 minutes d) 7 minutes
Answer: c) 6 minutes
24. A de-icing pad can handle 1 wide-body or 2 narrow-body aircraft at a time. If there are 5 wide-
body and 8 narrow-body aircraft to be de-iced, what's the minimum number of cycles needed?
a) 7 b) 8 c) 9 d) 10
Answer: c) 9
25. If a de-icing operation uses 1.5 liters of fluid per square meter of aircraft surface, how many
square meters can be treated with a 1000-liter tank?
a) 600 m² b) 650 m² c) 666 m² d) 700 m²
Answer: c) 666 m²
26. An airport handles 200 flights per day in winter. If 75% of these flights require de-icing and each
operation uses 400 liters of fluid, how many liters are used daily?
a) 55,000 b) 60,000 c) 65,000 d) 70,000
Answer: b) 60,000
27. If the viscosity of de-icing fluid increases by 5% for every 1°C drop in temperature, what is the
percentage increase in viscosity when the temperature drops from 0°C to -8°C?
a) 35% b) 40% c) 45% d) 50%
Answer: b) 40%
28. A de-icing truck pumps fluid at a rate of 40 gallons per minute. How many minutes will it take to
empty a 1500-gallon tank?
a) 35.5 minutes b) 37.5 minutes c) 39.5 minutes d) 41.5 minutes
Answer: b) 37.5 minutes
29. If a heated hangar can raise the temperature of an aircraft by 2°C every 5 minutes, how long will
it take to raise the temperature from -15°C to 5°C?
a) 40 minutes b) 45 minutes c) 50 minutes d) 55 minutes
Answer: c) 50 minutes
30. An airline uses 3 different de-icing fluid mixtures: 20%, 40%, and 60% glycol. If they use 1000
liters of each, what is the total amount of pure glycol used?
a) 1000 liters b) 1100 liters c) 1200 liters d) 1300 liters
Answer: c) 1200 liters
31. If a de-icing pad can process 1 aircraft every 12 minutes, how many aircraft can it handle in an 8-
hour shift, assuming no breaks?
a) 38 b) 39 c) 40 d) 41
Answer: c) 40
32. A new de-icing technology claims to reduce fluid usage by 25%. If an airport currently uses
80,000 liters per month, how much will they use with the new technology?
a) 55,000 liters b) 60,000 liters c) 65,000 liters d) 70,000 liters
Answer: b) 60,000 liters
33. If the freezing point of pure water is 0°C and a 50% glycol solution freezes at -34°C, what is the
approximate freezing point of a 25% glycol solution?
a) -14°C b) -16°C c) -17°C d) -19°C
Answer: c) -17°C
34. An aircraft has a wing span of 40 meters and a chord length of 5 meters. If de-icing fluid is applied
at 0.5 liters per square meter, how many liters are needed for both wings?
a) 180 liters b) 190 liters c) 200 liters d) 210 liters
Answer: c) 200 liters
35. If a de-icing operation costs $500 per aircraft and an airline performs this operation on 30% of its
200 daily flights during winter, what is the daily cost?
a) $28,000 b) $29,000 c) $30,000 d) $31,000
Answer: c) $30,000
36. A pneumatic de-icing boot inflates to 3 cm thickness. If it covers a wing section that is 10 meters
long and 1 meter wide, what volume of air is needed to inflate it?
a) 0.25 m³ b) 0.3 m³ c) 0.35 m³ d) 0.4 m³
Answer: b) 0.3 m³
37. If an electrochemical de-icing system uses 2 amps of current per square meter at 24 volts, what is
the power consumption for a 50 m² surface?
a) 2000 watts b) 2200 watts c) 2400 watts d) 2600 watts
Answer: c) 2400 watts
38. A de-icing fluid mixture is 30% glycol by volume. How many liters of glycol should be added to
700 liters of this mixture to increase the concentration to 40%?
a) 100 liters b) 110 liters c) 120 liters d) 130 liters
Answer: c) 120 liters
39. If a de-icing truck can service an aircraft in 15 minutes and spends 5 minutes moving between
aircraft, how many aircraft can it service in 2 hours?
a) 5 b) 6 c) 7 d) 8
Answer: b) 6
40. An airport uses 1.5 million liters of de-icing fluid annually. If the fluid costs $2 per liter and they
implement a recycling system that recovers 40% of the fluid, how much money will they save per
year?
a) $1,100,000 b) $1,150,000 c) $1,200,000 d) $1,250,000
Answer: c) $1,200,000
41. If an infrared de-icing system uses 250 kW of power and operates for 8 hours a day, 120 days per
year, how many megawatt-hours (MWh) of energy does it consume annually?
a) 220 MWh b) 230 MWh c) 240 MWh d) 250 MWh
Answer: c) 240 MWh
42. A de-icing fluid sprayer covers an area of 3 m²/second. If an aircraft has a total surface area of 450
m² and 80% needs to be sprayed, how long will the operation take?
a) 110 seconds b) 120 seconds c) 130 seconds d) 140 seconds
Answer: b) 120 seconds
43. If the density of a de-icing fluid is 1.05 g/cm³, what is the mass of fluid in a 200-liter tank?
a) 200 kg b) 205 kg c) 210 kg d) 215 kg
Answer: c) 210 kg
44. An airline uses 100,000 liters of de-icing fluid per month at a cost of $3 per liter. If they switch to
a more expensive fluid that costs $4 per liter but reduces consumption by 20%, what is their monthly
savings?
a) $20,000 b) $30,000 c) $40,000 d) $50,000
Answer: c) $40,000
45. If a de-icing pad can handle 3 narrow-body or 1 wide-body aircraft at a time, and it takes 20
minutes to de-ice a narrow-body and 40 minutes for a wide-body, how long will it take to de-ice 9
narrow-body and 3 wide-body aircraft?
a) 140 minutes b) 160 minutes c) 180 minutes d) 200 minutes
Answer: b) 160 minutes
A de-icing operation takes 20 minutes per aircraft. If there are 12 aircraft to be de-iced and 3 de-icing
trucks available, how long will the entire operation take?
a) 60 minutes b) 80 minutes c) 100 minutes d) 120 minutes
Answer: b) 80 minutes
11. If a de-icing fluid mixture is 20% glycol and 80% water, how many liters of glycol are in a 350-liter
mixture?
a) 50 liters b) 60 liters c) 70 liters d) 80 liters
Answer: c) 70 liters
12. An aircraft's anti-icing system can prevent ice formation for 3 hours. If a flight duration is 7.5
hours, how many times does the system need to be activated?
a) 2 times b) 3 times c) 4 times d) 5 times
Answer: b) 3 times
13. A de-icing pad can accommodate 4 aircraft simultaneously. If 30 aircraft need de-icing and each
operation takes 15 minutes, how long will the entire process take?
a) 1 hour 45 minutes b) 1 hour 52.5 minutes c) 2 hours d) 2 hours 15 minutes
Answer: b) 1 hour 52.5 minutes
14. If a pneumatic de-icing boot inflates and deflates 3 times per minute, how many cycles will it
complete in a 2-hour flight?
a) 320 b) 340 c) 360 d) 380
Answer: c) 360
15. An electric heating element uses 500 watts per meter of length. If an aircraft's leading edge is 30
meters long and requires heating on both sides, what is the total power consumption?
a) 15 kW b) 20 kW c) 25 kW d) 30 kW
Answer: d) 30 kW
16. A de-icing fluid sprayer covers 2 m²/second. How long will it take to cover an aircraft with a total
surface area of 300 m²?
a) 120 seconds b) 140 seconds c) 150 seconds d) 160 seconds
Answer: c) 150 seconds
17. If the freezing point of a 50% glycol solution is -34°C, and it increases by 1°C for every 1%
decrease in concentration, what is the freezing point of a 40% solution?
a) -24°C b) -26°C c) -28°C d) -30°C
Answer: a) -24°C
18. An airport uses 50,000 liters of de-icing fluid per month. If they switch to a new system that
reduces consumption by 15%, how many liters will they save in a year?
a) 75,000 b) 80,000 c) 85,000 d) 90,000
Answer: d) 90,000
19. If a de-icing truck can hold 3000 liters and uses 200 liters per aircraft, how many aircraft can it
service before needing a refill?
a) 12 b) 13 c) 14 d) 15
Answer: d) 15
20. An infrared de-icing system uses 300 kW of power and can de-ice an aircraft in 6 minutes. How
much energy (in kWh) does it consume per aircraft?
a) 20 kWh b) 25 kWh c) 30 kWh d) 35 kWh
Answer: c) 30 kWh
21. If a de-icing fluid has a specific gravity of 1.1 and a 55-gallon drum is filled to 80% capacity, what
is the weight of the fluid in kilograms? (1 gallon ≈ 3.78541 liters)
a) 182 kg b) 192 kg c) 202 kg d) 212 kg
Answer: b) 192 kg
22. An airline spends $500,000 on de-icing fluid annually. If they invest in a new system that costs
$2,000,000 but reduces fluid consumption by 30%, how many years will it take for the investment to
break even?
a) 12 years b) 13 years c) 14 years d) 15 years
Answer: b) 13 years
23. If an electrothermal de-icing system heats the surface at a rate of 5°C per minute and needs to
raise the temperature from -10°C to 20°C, how long will it take?
a) 4 minutes b) 5 minutes c) 6 minutes d) 7 minutes
Answer: c) 6 minutes
24. A de-icing pad can handle 1 wide-body or 2 narrow-body aircraft at a time. If there are 5 wide-
body and 8 narrow-body aircraft to be de-iced, what's the minimum number of cycles needed?
a) 7 b) 8 c) 9 d) 10
Answer: c) 9
25. If a de-icing operation uses 1.5 liters of fluid per square meter of aircraft surface, how many
square meters can be treated with a 1000-liter tank?
a) 600 m² b) 650 m² c) 666 m² d) 700 m²
Answer: c) 666 m²
26. An airport handles 200 flights per day in winter. If 75% of these flights require de-icing and each
operation uses 400 liters of fluid, how many liters are used daily?
a) 55,000 b) 60,000 c) 65,000 d) 70,000
Answer: b) 60,000
27. If the viscosity of de-icing fluid increases by 5% for every 1°C drop in temperature, what is the
percentage increase in viscosity when the temperature drops from 0°C to -8°C?
a) 35% b) 40% c) 45% d) 50%
Answer: b) 40%
28. A de-icing truck pumps fluid at a rate of 40 gallons per minute. How many minutes will it take to
empty a 1500-gallon tank?
a) 35.5 minutes b) 37.5 minutes c) 39.5 minutes d) 41.5 minutes
Answer: b) 37.5 minutes
29. If a heated hangar can raise the temperature of an aircraft by 2°C every 5 minutes, how long will
it take to raise the temperature from -15°C to 5°C?
a) 40 minutes b) 45 minutes c) 50 minutes d) 55 minutes
Answer: c) 50 minutes
30. An airline uses 3 different de-icing fluid mixtures: 20%, 40%, and 60% glycol. If they use 1000
liters of each, what is the total amount of pure glycol used?
a) 1000 liters b) 1100 liters c) 1200 liters d) 1300 liters
Answer: c) 1200 liters
31. If a de-icing pad can process 1 aircraft every 12 minutes, how many aircraft can it handle in an 8-
hour shift, assuming no breaks?
a) 38 b) 39 c) 40 d) 41
Answer: c) 40
32. A new de-icing technology claims to reduce fluid usage by 25%. If an airport currently uses
80,000 liters per month, how much will they use with the new technology?
a) 55,000 liters b) 60,000 liters c) 65,000 liters d) 70,000 liters
Answer: b) 60,000 liters
33. If the freezing point of pure water is 0°C and a 50% glycol solution freezes at -34°C, what is the
approximate freezing point of a 25% glycol solution?
a) -14°C b) -16°C c) -17°C d) -19°C
Answer: c) -17°C
34. An aircraft has a wing span of 40 meters and a chord length of 5 meters. If de-icing fluid is applied
at 0.5 liters per square meter, how many liters are needed for both wings?
a) 180 liters b) 190 liters c) 200 liters d) 210 liters
Answer: c) 200 liters
35. If a de-icing operation costs $500 per aircraft and an airline performs this operation on 30% of its
200 daily flights during winter, what is the daily cost?
a) $28,000 b) $29,000 c) $30,000 d) $31,000
Answer: c) $30,000
36. A pneumatic de-icing boot inflates to 3 cm thickness. If it covers a wing section that is 10 meters
long and 1 meter wide, what volume of air is needed to inflate it?
a) 0.25 m³ b) 0.3 m³ c) 0.35 m³ d) 0.4 m³
Answer: b) 0.3 m³
37. If an electrochemical de-icing system uses 2 amps of current per square meter at 24 volts, what is
the power consumption for a 50 m² surface?
a) 2000 watts b) 2200 watts c) 2400 watts d) 2600 watts
Answer: c) 2400 watts
38. A de-icing fluid mixture is 30% glycol by volume. How many liters of glycol should be added to
700 liters of this mixture to increase the concentration to 40%?
a) 100 liters b) 110 liters c) 120 liters d) 130 liters
Answer: c) 120 liters
39. If a de-icing truck can service an aircraft in 15 minutes and spends 5 minutes moving between
aircraft, how many aircraft can it service in 2 hours?
a) 5 b) 6 c) 7 d) 8
Answer: b) 6
40. An airport uses 1.5 million liters of de-icing fluid annually. If the fluid costs $2 per liter and they
implement a recycling system that recovers 40% of the fluid, how much money will they save per
year?
a) $1,100,000 b) $1,150,000 c) $1,200,000 d) $1,250,000
Answer: c) $1,200,000
41. If an infrared de-icing system uses 250 kW of power and operates for 8 hours a day, 120 days per
year, how many megawatt-hours (MWh) of energy does it consume annually?
a) 220 MWh b) 230 MWh c) 240 MWh d) 250 MWh
Answer: c) 240 MWh
42. A de-icing fluid sprayer covers an area of 3 m²/second. If an aircraft has a total surface area of 450
m² and 80% needs to be sprayed, how long will the operation take?
a) 110 seconds b) 120 seconds c) 130 seconds d) 140 seconds
Answer: b) 120 seconds
43. If the density of a de-icing fluid is 1.05 g/cm³, what is the mass of fluid in a 200-liter tank?
a) 200 kg b) 205 kg c) 210 kg d) 215 kg
Answer: c) 210 kg
44. An airline uses 100,000 liters of de-icing fluid per month at a cost of $3 per liter. If they switch to
a more expensive fluid that costs $4 per liter but reduces consumption by 20%, what is their monthly
savings?
a) $20,000 b) $30,000 c) $40,000 d) $50,000
Answer: c) $40,000
45. If a de-icing pad can handle 3 narrow-body or 1 wide-body aircraft at a time, and it takes 20
minutes to de-ice a narrow-body and 40 minutes for a wide-body, how long will it take to de-ice 9
narrow-body and 3 wide-body aircraft?
a) 140 minutes b) 160 minutes c) 180 minutes d) 200 minutes
Answer: b) 160 minutes
A de-icing operation takes 20 minutes per aircraft. If there are 12 aircraft to be de-iced and 3 de-icing
trucks available, how long will the entire operation take?
a) 60 minutes b) 80 minutes c) 100 minutes d) 120 minutes
Answer: b) 80 minutes
11. If a de-icing fluid mixture is 20% glycol and 80% water, how many liters of glycol are in a 350-liter
mixture?
a) 50 liters b) 60 liters c) 70 liters d) 80 liters
Answer: c) 70 liters
12. An aircraft's anti-icing system can prevent ice formation for 3 hours. If a flight duration is 7.5
hours, how many times does the system need to be activated?
a) 2 times b) 3 times c) 4 times d) 5 times
Answer: b) 3 times
13. A de-icing pad can accommodate 4 aircraft simultaneously. If 30 aircraft need de-icing and each
operation takes 15 minutes, how long will the entire process take?
a) 1 hour 45 minutes b) 1 hour 52.5 minutes c) 2 hours d) 2 hours 15 minutes
Answer: b) 1 hour 52.5 minutes
14. If a pneumatic de-icing boot inflates and deflates 3 times per minute, how many cycles will it
complete in a 2-hour flight?
a) 320 b) 340 c) 360 d) 380
Answer: c) 360
15. An electric heating element uses 500 watts per meter of length. If an aircraft's leading edge is 30
meters long and requires heating on both sides, what is the total power consumption?
a) 15 kW b) 20 kW c) 25 kW d) 30 kW
Answer: d) 30 kW
16. A de-icing fluid sprayer covers 2 m²/second. How long will it take to cover an aircraft with a total
surface area of 300 m²?
a) 120 seconds b) 140 seconds c) 150 seconds d) 160 seconds
Answer: c) 150 seconds
17. If the freezing point of a 50% glycol solution is -34°C, and it increases by 1°C for every 1%
decrease in concentration, what is the freezing point of a 40% solution?
a) -24°C b) -26°C c) -28°C d) -30°C
Answer: a) -24°C
18. An airport uses 50,000 liters of de-icing fluid per month. If they switch to a new system that
reduces consumption by 15%, how many liters will they save in a year?
a) 75,000 b) 80,000 c) 85,000 d) 90,000
Answer: d) 90,000
19. If a de-icing truck can hold 3000 liters and uses 200 liters per aircraft, how many aircraft can it
service before needing a refill?
a) 12 b) 13 c) 14 d) 15
Answer: d) 15
20. An infrared de-icing system uses 300 kW of power and can de-ice an aircraft in 6 minutes. How
much energy (in kWh) does it consume per aircraft?
a) 20 kWh b) 25 kWh c) 30 kWh d) 35 kWh
Answer: c) 30 kWh
21. If a de-icing fluid has a specific gravity of 1.1 and a 55-gallon drum is filled to 80% capacity, what
is the weight of the fluid in kilograms? (1 gallon ≈ 3.78541 liters)
a) 182 kg b) 192 kg c) 202 kg d) 212 kg
Answer: b) 192 kg
22. An airline spends $500,000 on de-icing fluid annually. If they invest in a new system that costs
$2,000,000 but reduces fluid consumption by 30%, how many years will it take for the investment to
break even?
a) 12 years b) 13 years c) 14 years d) 15 years
Answer: b) 13 years
23. If an electrothermal de-icing system heats the surface at a rate of 5°C per minute and needs to
raise the temperature from -10°C to 20°C, how long will it take?
a) 4 minutes b) 5 minutes c) 6 minutes d) 7 minutes
Answer: c) 6 minutes
24. A de-icing pad can handle 1 wide-body or 2 narrow-body aircraft at a time. If there are 5 wide-
body and 8 narrow-body aircraft to be de-iced, what's the minimum number of cycles needed?
a) 7 b) 8 c) 9 d) 10
Answer: c) 9
25. If a de-icing operation uses 1.5 liters of fluid per square meter of aircraft surface, how many
square meters can be treated with a 1000-liter tank?
a) 600 m² b) 650 m² c) 666 m² d) 700 m²
Answer: c) 666 m²
26. An airport handles 200 flights per day in winter. If 75% of these flights require de-icing and each
operation uses 400 liters of fluid, how many liters are used daily?
a) 55,000 b) 60,000 c) 65,000 d) 70,000
Answer: b) 60,000
27. If the viscosity of de-icing fluid increases by 5% for every 1°C drop in temperature, what is the
percentage increase in viscosity when the temperature drops from 0°C to -8°C?
a) 35% b) 40% c) 45% d) 50%
Answer: b) 40%
28. A de-icing truck pumps fluid at a rate of 40 gallons per minute. How many minutes will it take to
empty a 1500-gallon tank?
a) 35.5 minutes b) 37.5 minutes c) 39.5 minutes d) 41.5 minutes
Answer: b) 37.5 minutes
29. If a heated hangar can raise the temperature of an aircraft by 2°C every 5 minutes, how long will
it take to raise the temperature from -15°C to 5°C?
a) 40 minutes b) 45 minutes c) 50 minutes d) 55 minutes
Answer: c) 50 minutes
30. An airline uses 3 different de-icing fluid mixtures: 20%, 40%, and 60% glycol. If they use 1000
liters of each, what is the total amount of pure glycol used?
a) 1000 liters b) 1100 liters c) 1200 liters d) 1300 liters
Answer: c) 1200 liters
31. If a de-icing pad can process 1 aircraft every 12 minutes, how many aircraft can it handle in an 8-
hour shift, assuming no breaks?
a) 38 b) 39 c) 40 d) 41
Answer: c) 40
32. A new de-icing technology claims to reduce fluid usage by 25%. If an airport currently uses
80,000 liters per month, how much will they use with the new technology?
a) 55,000 liters b) 60,000 liters c) 65,000 liters d) 70,000 liters
Answer: b) 60,000 liters
33. If the freezing point of pure water is 0°C and a 50% glycol solution freezes at -34°C, what is the
approximate freezing point of a 25% glycol solution?
a) -14°C b) -16°C c) -17°C d) -19°C
Answer: c) -17°C
34. An aircraft has a wing span of 40 meters and a chord length of 5 meters. If de-icing fluid is applied
at 0.5 liters per square meter, how many liters are needed for both wings?
a) 180 liters b) 190 liters c) 200 liters d) 210 liters
Answer: c) 200 liters
35. If a de-icing operation costs $500 per aircraft and an airline performs this operation on 30% of its
200 daily flights during winter, what is the daily cost?
a) $28,000 b) $29,000 c) $30,000 d) $31,000
Answer: c) $30,000
36. A pneumatic de-icing boot inflates to 3 cm thickness. If it covers a wing section that is 10 meters
long and 1 meter wide, what volume of air is needed to inflate it?
a) 0.25 m³ b) 0.3 m³ c) 0.35 m³ d) 0.4 m³
Answer: b) 0.3 m³
37. If an electrochemical de-icing system uses 2 amps of current per square meter at 24 volts, what is
the power consumption for a 50 m² surface?
a) 2000 watts b) 2200 watts c) 2400 watts d) 2600 watts
Answer: c) 2400 watts
38. A de-icing fluid mixture is 30% glycol by volume. How many liters of glycol should be added to
700 liters of this mixture to increase the concentration to 40%?
a) 100 liters b) 110 liters c) 120 liters d) 130 liters
Answer: c) 120 liters
39. If a de-icing truck can service an aircraft in 15 minutes and spends 5 minutes moving between
aircraft, how many aircraft can it service in 2 hours?
a) 5 b) 6 c) 7 d) 8
Answer: b) 6
40. An airport uses 1.5 million liters of de-icing fluid annually. If the fluid costs $2 per liter and they
implement a recycling system that recovers 40% of the fluid, how much money will they save per
year?
a) $1,100,000 b) $1,150,000 c) $1,200,000 d) $1,250,000
Answer: c) $1,200,000
41. If an infrared de-icing system uses 250 kW of power and operates for 8 hours a day, 120 days per
year, how many megawatt-hours (MWh) of energy does it consume annually?
a) 220 MWh b) 230 MWh c) 240 MWh d) 250 MWh
Answer: c) 240 MWh
42. A de-icing fluid sprayer covers an area of 3 m²/second. If an aircraft has a total surface area of 450
m² and 80% needs to be sprayed, how long will the operation take?
a) 110 seconds b) 120 seconds c) 130 seconds d) 140 seconds
Answer: b) 120 seconds
43. If the density of a de-icing fluid is 1.05 g/cm³, what is the mass of fluid in a 200-liter tank?
a) 200 kg b) 205 kg c) 210 kg d) 215 kg
Answer: c) 210 kg
44. An airline uses 100,000 liters of de-icing fluid per month at a cost of $3 per liter. If they switch to
a more expensive fluid that costs $4 per liter but reduces consumption by 20%, what is their monthly
savings?
a) $20,000 b) $30,000 c) $40,000 d) $50,000
Answer: c) $40,000
45. If a de-icing pad can handle 3 narrow-body or 1 wide-body aircraft at a time, and it takes 20
minutes to de-ice a narrow-body and 40 minutes for a wide-body, how long will it take to de-ice 9
narrow-body and 3 wide-body aircraft?
a) 140 minutes b) 160 minutes c) 180 minutes d) 200 minutes
Answer: b) 160 minutes
A de-icing operation takes 20 minutes per aircraft. If there are 12 aircraft to be de-iced and 3 de-icing
trucks available, how long will the entire operation take?
a) 60 minutes b) 80 minutes c) 100 minutes d) 120 minutes
Answer: b) 80 minutes
11. If a de-icing fluid mixture is 20% glycol and 80% water, how many liters of glycol are in a 350-liter
mixture?
a) 50 liters b) 60 liters c) 70 liters d) 80 liters
Answer: c) 70 liters
12. An aircraft's anti-icing system can prevent ice formation for 3 hours. If a flight duration is 7.5
hours, how many times does the system need to be activated?
a) 2 times b) 3 times c) 4 times d) 5 times
Answer: b) 3 times
13. A de-icing pad can accommodate 4 aircraft simultaneously. If 30 aircraft need de-icing and each
operation takes 15 minutes, how long will the entire process take?
a) 1 hour 45 minutes b) 1 hour 52.5 minutes c) 2 hours d) 2 hours 15 minutes
Answer: b) 1 hour 52.5 minutes
14. If a pneumatic de-icing boot inflates and deflates 3 times per minute, how many cycles will it
complete in a 2-hour flight?
a) 320 b) 340 c) 360 d) 380
Answer: c) 360
15. An electric heating element uses 500 watts per meter of length. If an aircraft's leading edge is 30
meters long and requires heating on both sides, what is the total power consumption?
a) 15 kW b) 20 kW c) 25 kW d) 30 kW
Answer: d) 30 kW
16. A de-icing fluid sprayer covers 2 m²/second. How long will it take to cover an aircraft with a total
surface area of 300 m²?
a) 120 seconds b) 140 seconds c) 150 seconds d) 160 seconds
Answer: c) 150 seconds
17. If the freezing point of a 50% glycol solution is -34°C, and it increases by 1°C for every 1%
decrease in concentration, what is the freezing point of a 40% solution?
a) -24°C b) -26°C c) -28°C d) -30°C
Answer: a) -24°C
18. An airport uses 50,000 liters of de-icing fluid per month. If they switch to a new system that
reduces consumption by 15%, how many liters will they save in a year?
a) 75,000 b) 80,000 c) 85,000 d) 90,000
Answer: d) 90,000
19. If a de-icing truck can hold 3000 liters and uses 200 liters per aircraft, how many aircraft can it
service before needing a refill?
a) 12 b) 13 c) 14 d) 15
Answer: d) 15
20. An infrared de-icing system uses 300 kW of power and can de-ice an aircraft in 6 minutes. How
much energy (in kWh) does it consume per aircraft?
a) 20 kWh b) 25 kWh c) 30 kWh d) 35 kWh
Answer: c) 30 kWh
21. If a de-icing fluid has a specific gravity of 1.1 and a 55-gallon drum is filled to 80% capacity, what
is the weight of the fluid in kilograms? (1 gallon ≈ 3.78541 liters)
a) 182 kg b) 192 kg c) 202 kg d) 212 kg
Answer: b) 192 kg
22. An airline spends $500,000 on de-icing fluid annually. If they invest in a new system that costs
$2,000,000 but reduces fluid consumption by 30%, how many years will it take for the investment to
break even?
a) 12 years b) 13 years c) 14 years d) 15 years
Answer: b) 13 years
23. If an electrothermal de-icing system heats the surface at a rate of 5°C per minute and needs to
raise the temperature from -10°C to 20°C, how long will it take?
a) 4 minutes b) 5 minutes c) 6 minutes d) 7 minutes
Answer: c) 6 minutes
24. A de-icing pad can handle 1 wide-body or 2 narrow-body aircraft at a time. If there are 5 wide-
body and 8 narrow-body aircraft to be de-iced, what's the minimum number of cycles needed?
a) 7 b) 8 c) 9 d) 10
Answer: c) 9
25. If a de-icing operation uses 1.5 liters of fluid per square meter of aircraft surface, how many
square meters can be treated with a 1000-liter tank?
a) 600 m² b) 650 m² c) 666 m² d) 700 m²
Answer: c) 666 m²
26. An airport handles 200 flights per day in winter. If 75% of these flights require de-icing and each
operation uses 400 liters of fluid, how many liters are used daily?
a) 55,000 b) 60,000 c) 65,000 d) 70,000
Answer: b) 60,000
27. If the viscosity of de-icing fluid increases by 5% for every 1°C drop in temperature, what is the
percentage increase in viscosity when the temperature drops from 0°C to -8°C?
a) 35% b) 40% c) 45% d) 50%
Answer: b) 40%
28. A de-icing truck pumps fluid at a rate of 40 gallons per minute. How many minutes will it take to
empty a 1500-gallon tank?
a) 35.5 minutes b) 37.5 minutes c) 39.5 minutes d) 41.5 minutes
Answer: b) 37.5 minutes
29. If a heated hangar can raise the temperature of an aircraft by 2°C every 5 minutes, how long will
it take to raise the temperature from -15°C to 5°C?
a) 40 minutes b) 45 minutes c) 50 minutes d) 55 minutes
Answer: c) 50 minutes
30. An airline uses 3 different de-icing fluid mixtures: 20%, 40%, and 60% glycol. If they use 1000
liters of each, what is the total amount of pure glycol used?
a) 1000 liters b) 1100 liters c) 1200 liters d) 1300 liters
Answer: c) 1200 liters
31. If a de-icing pad can process 1 aircraft every 12 minutes, how many aircraft can it handle in an 8-
hour shift, assuming no breaks?
a) 38 b) 39 c) 40 d) 41
Answer: c) 40
32. A new de-icing technology claims to reduce fluid usage by 25%. If an airport currently uses
80,000 liters per month, how much will they use with the new technology?
a) 55,000 liters b) 60,000 liters c) 65,000 liters d) 70,000 liters
Answer: b) 60,000 liters
33. If the freezing point of pure water is 0°C and a 50% glycol solution freezes at -34°C, what is the
approximate freezing point of a 25% glycol solution?
a) -14°C b) -16°C c) -17°C d) -19°C
Answer: c) -17°C
34. An aircraft has a wing span of 40 meters and a chord length of 5 meters. If de-icing fluid is applied
at 0.5 liters per square meter, how many liters are needed for both wings?
a) 180 liters b) 190 liters c) 200 liters d) 210 liters
Answer: c) 200 liters
35. If a de-icing operation costs $500 per aircraft and an airline performs this operation on 30% of its
200 daily flights during winter, what is the daily cost?
a) $28,000 b) $29,000 c) $30,000 d) $31,000
Answer: c) $30,000
36. A pneumatic de-icing boot inflates to 3 cm thickness. If it covers a wing section that is 10 meters
long and 1 meter wide, what volume of air is needed to inflate it?
a) 0.25 m³ b) 0.3 m³ c) 0.35 m³ d) 0.4 m³
Answer: b) 0.3 m³
37. If an electrochemical de-icing system uses 2 amps of current per square meter at 24 volts, what is
the power consumption for a 50 m² surface?
a) 2000 watts b) 2200 watts c) 2400 watts d) 2600 watts
Answer: c) 2400 watts
38. A de-icing fluid mixture is 30% glycol by volume. How many liters of glycol should be added to
700 liters of this mixture to increase the concentration to 40%?
a) 100 liters b) 110 liters c) 120 liters d) 130 liters
Answer: c) 120 liters
39. If a de-icing truck can service an aircraft in 15 minutes and spends 5 minutes moving between
aircraft, how many aircraft can it service in 2 hours?
a) 5 b) 6 c) 7 d) 8
Answer: b) 6
40. An airport uses 1.5 million liters of de-icing fluid annually. If the fluid costs $2 per liter and they
implement a recycling system that recovers 40% of the fluid, how much money will they save per
year?
a) $1,100,000 b) $1,150,000 c) $1,200,000 d) $1,250,000
Answer: c) $1,200,000
41. If an infrared de-icing system uses 250 kW of power and operates for 8 hours a day, 120 days per
year, how many megawatt-hours (MWh) of energy does it consume annually?
a) 220 MWh b) 230 MWh c) 240 MWh d) 250 MWh
Answer: c) 240 MWh
42. A de-icing fluid sprayer covers an area of 3 m²/second. If an aircraft has a total surface area of 450
m² and 80% needs to be sprayed, how long will the operation take?
a) 110 seconds b) 120 seconds c) 130 seconds d) 140 seconds
Answer: b) 120 seconds
43. If the density of a de-icing fluid is 1.05 g/cm³, what is the mass of fluid in a 200-liter tank?
a) 200 kg b) 205 kg c) 210 kg d) 215 kg
Answer: c) 210 kg
44. An airline uses 100,000 liters of de-icing fluid per month at a cost of $3 per liter. If they switch to
a more expensive fluid that costs $4 per liter but reduces consumption by 20%, what is their monthly
savings?
a) $20,000 b) $30,000 c) $40,000 d) $50,000
Answer: c) $40,000
45. If a de-icing pad can handle 3 narrow-body or 1 wide-body aircraft at a time, and it takes 20
minutes to de-ice a narrow-body and 40 minutes for a wide-body, how long will it take to de-ice 9
narrow-body and 3 wide-body aircraft?
a) 140 minutes b) 160 minutes c) 180 minutes d) 200 minutes
Answer: b) 160 minutes
A de-icing operation takes 20 minutes per aircraft. If there are 12 aircraft to be de-iced and 3 de-icing
trucks available, how long will the entire operation take?
a) 60 minutes b) 80 minutes c) 100 minutes d) 120 minutes
Answer: b) 80 minutes
11. If a de-icing fluid mixture is 20% glycol and 80% water, how many liters of glycol are in a 350-liter
mixture?
a) 50 liters b) 60 liters c) 70 liters d) 80 liters
Answer: c) 70 liters
12. An aircraft's anti-icing system can prevent ice formation for 3 hours. If a flight duration is 7.5
hours, how many times does the system need to be activated?
a) 2 times b) 3 times c) 4 times d) 5 times
Answer: b) 3 times
13. A de-icing pad can accommodate 4 aircraft simultaneously. If 30 aircraft need de-icing and each
operation takes 15 minutes, how long will the entire process take?
a) 1 hour 45 minutes b) 1 hour 52.5 minutes c) 2 hours d) 2 hours 15 minutes
Answer: b) 1 hour 52.5 minutes
14. If a pneumatic de-icing boot inflates and deflates 3 times per minute, how many cycles will it
complete in a 2-hour flight?
a) 320 b) 340 c) 360 d) 380
Answer: c) 360
15. An electric heating element uses 500 watts per meter of length. If an aircraft's leading edge is 30
meters long and requires heating on both sides, what is the total power consumption?
a) 15 kW b) 20 kW c) 25 kW d) 30 kW
Answer: d) 30 kW
16. A de-icing fluid sprayer covers 2 m²/second. How long will it take to cover an aircraft with a total
surface area of 300 m²?
a) 120 seconds b) 140 seconds c) 150 seconds d) 160 seconds
Answer: c) 150 seconds
17. If the freezing point of a 50% glycol solution is -34°C, and it increases by 1°C for every 1%
decrease in concentration, what is the freezing point of a 40% solution?
a) -24°C b) -26°C c) -28°C d) -30°C
Answer: a) -24°C
18. An airport uses 50,000 liters of de-icing fluid per month. If they switch to a new system that
reduces consumption by 15%, how many liters will they save in a year?
a) 75,000 b) 80,000 c) 85,000 d) 90,000
Answer: d) 90,000
19. If a de-icing truck can hold 3000 liters and uses 200 liters per aircraft, how many aircraft can it
service before needing a refill?
a) 12 b) 13 c) 14 d) 15
Answer: d) 15
20. An infrared de-icing system uses 300 kW of power and can de-ice an aircraft in 6 minutes. How
much energy (in kWh) does it consume per aircraft?
a) 20 kWh b) 25 kWh c) 30 kWh d) 35 kWh
Answer: c) 30 kWh
21. If a de-icing fluid has a specific gravity of 1.1 and a 55-gallon drum is filled to 80% capacity, what
is the weight of the fluid in kilograms? (1 gallon ≈ 3.78541 liters)
a) 182 kg b) 192 kg c) 202 kg d) 212 kg
Answer: b) 192 kg
22. An airline spends $500,000 on de-icing fluid annually. If they invest in a new system that costs
$2,000,000 but reduces fluid consumption by 30%, how many years will it take for the investment to
break even?
a) 12 years b) 13 years c) 14 years d) 15 years
Answer: b) 13 years
23. If an electrothermal de-icing system heats the surface at a rate of 5°C per minute and needs to
raise the temperature from -10°C to 20°C, how long will it take?
a) 4 minutes b) 5 minutes c) 6 minutes d) 7 minutes
Answer: c) 6 minutes
24. A de-icing pad can handle 1 wide-body or 2 narrow-body aircraft at a time. If there are 5 wide-
body and 8 narrow-body aircraft to be de-iced, what's the minimum number of cycles needed?
a) 7 b) 8 c) 9 d) 10
Answer: c) 9
25. If a de-icing operation uses 1.5 liters of fluid per square meter of aircraft surface, how many
square meters can be treated with a 1000-liter tank?
a) 600 m² b) 650 m² c) 666 m² d) 700 m²
Answer: c) 666 m²
26. An airport handles 200 flights per day in winter. If 75% of these flights require de-icing and each
operation uses 400 liters of fluid, how many liters are used daily?
a) 55,000 b) 60,000 c) 65,000 d) 70,000
Answer: b) 60,000
27. If the viscosity of de-icing fluid increases by 5% for every 1°C drop in temperature, what is the
percentage increase in viscosity when the temperature drops from 0°C to -8°C?
a) 35% b) 40% c) 45% d) 50%
Answer: b) 40%
28. A de-icing truck pumps fluid at a rate of 40 gallons per minute. How many minutes will it take to
empty a 1500-gallon tank?
a) 35.5 minutes b) 37.5 minutes c) 39.5 minutes d) 41.5 minutes
Answer: b) 37.5 minutes
29. If a heated hangar can raise the temperature of an aircraft by 2°C every 5 minutes, how long will
it take to raise the temperature from -15°C to 5°C?
a) 40 minutes b) 45 minutes c) 50 minutes d) 55 minutes
Answer: c) 50 minutes
30. An airline uses 3 different de-icing fluid mixtures: 20%, 40%, and 60% glycol. If they use 1000
liters of each, what is the total amount of pure glycol used?
a) 1000 liters b) 1100 liters c) 1200 liters d) 1300 liters
Answer: c) 1200 liters
31. If a de-icing pad can process 1 aircraft every 12 minutes, how many aircraft can it handle in an 8-
hour shift, assuming no breaks?
a) 38 b) 39 c) 40 d) 41
Answer: c) 40
32. A new de-icing technology claims to reduce fluid usage by 25%. If an airport currently uses
80,000 liters per month, how much will they use with the new technology?
a) 55,000 liters b) 60,000 liters c) 65,000 liters d) 70,000 liters
Answer: b) 60,000 liters
33. If the freezing point of pure water is 0°C and a 50% glycol solution freezes at -34°C, what is the
approximate freezing point of a 25% glycol solution?
a) -14°C b) -16°C c) -17°C d) -19°C
Answer: c) -17°C
34. An aircraft has a wing span of 40 meters and a chord length of 5 meters. If de-icing fluid is applied
at 0.5 liters per square meter, how many liters are needed for both wings?
a) 180 liters b) 190 liters c) 200 liters d) 210 liters
Answer: c) 200 liters
35. If a de-icing operation costs $500 per aircraft and an airline performs this operation on 30% of its
200 daily flights during winter, what is the daily cost?
a) $28,000 b) $29,000 c) $30,000 d) $31,000
Answer: c) $30,000
36. A pneumatic de-icing boot inflates to 3 cm thickness. If it covers a wing section that is 10 meters
long and 1 meter wide, what volume of air is needed to inflate it?
a) 0.25 m³ b) 0.3 m³ c) 0.35 m³ d) 0.4 m³
Answer: b) 0.3 m³
37. If an electrochemical de-icing system uses 2 amps of current per square meter at 24 volts, what is
the power consumption for a 50 m² surface?
a) 2000 watts b) 2200 watts c) 2400 watts d) 2600 watts
Answer: c) 2400 watts
38. A de-icing fluid mixture is 30% glycol by volume. How many liters of glycol should be added to
700 liters of this mixture to increase the concentration to 40%?
a) 100 liters b) 110 liters c) 120 liters d) 130 liters
Answer: c) 120 liters
39. If a de-icing truck can service an aircraft in 15 minutes and spends 5 minutes moving between
aircraft, how many aircraft can it service in 2 hours?
a) 5 b) 6 c) 7 d) 8
Answer: b) 6
40. An airport uses 1.5 million liters of de-icing fluid annually. If the fluid costs $2 per liter and they
implement a recycling system that recovers 40% of the fluid, how much money will they save per
year?
a) $1,100,000 b) $1,150,000 c) $1,200,000 d) $1,250,000
Answer: c) $1,200,000
41. If an infrared de-icing system uses 250 kW of power and operates for 8 hours a day, 120 days per
year, how many megawatt-hours (MWh) of energy does it consume annually?
a) 220 MWh b) 230 MWh c) 240 MWh d) 250 MWh
Answer: c) 240 MWh
42. A de-icing fluid sprayer covers an area of 3 m²/second. If an aircraft has a total surface area of 450
m² and 80% needs to be sprayed, how long will the operation take?
a) 110 seconds b) 120 seconds c) 130 seconds d) 140 seconds
Answer: b) 120 seconds
43. If the density of a de-icing fluid is 1.05 g/cm³, what is the mass of fluid in a 200-liter tank?
a) 200 kg b) 205 kg c) 210 kg d) 215 kg
Answer: c) 210 kg
44. An airline uses 100,000 liters of de-icing fluid per month at a cost of $3 per liter. If they switch to
a more expensive fluid that costs $4 per liter but reduces consumption by 20%, what is their monthly
savings?
a) $20,000 b) $30,000 c) $40,000 d) $50,000
Answer: c) $40,000
45. If a de-icing pad can handle 3 narrow-body or 1 wide-body aircraft at a time, and it takes 20
minutes to de-ice a narrow-body and 40 minutes for a wide-body, how long will it take to de-ice 9
narrow-body and 3 wide-body aircraft?
a) 140 minutes b) 160 minutes c) 180 minutes d) 200 minutes
Answer: b) 160 minutes
46. An electrothermal de-icing system raises the temperature of a surface by 30°C in 2 minutes. If it
needs to raise the temperature from -20°C to 10°C, how long will it take?
a) 1 minute b) 2 minutes c) 3 minutes d) 4 minutes
Answer: b) 2 minutes
47. If a de-icing fluid has a freezing point of -40°C when pure, and each 10% dilution with water
raises the freezing point by 8°C, what is the freezing point of a 70% solution?
a) -
