N60381 Accident Case Study 1
N60381 Accident Case Study
Michael Hicks
AVIA 340 Aviation Weather
N60381 Accident Case Study 2
N60381 Accident Case Study
Introduction
On February 6, 2020, N60381, a Cessna model 182, departed Jackson-Hawkins Field
Airport (HKS) with an instrument flight plan filed for Shreveport Regional Airport (SHV).
(NTSB. 2020.). Marginal visual meteorological conditions (MVMC) to instrument
meteorological conditions (IMC) were present and prevailed along the aircraft’s flight path.
(Eick. 2020.). After departure, the aircraft is at 6,000 feet and the pilot contacts Air Traffic
Control (ATC) to report a buildup of ice on the aircraft and to request a lower altitude to reduce
the ice buildup. Air traffic control then cleared the accident flight for a lower altitude. Shortly
after the altitude change the pilot requested to divert to Ruston Regional Airport (RSN) to land
and remove the ice buildup. ATC cleared the pilot for an RNAV approach to runway 36 as RSN.
Seven minutes after the request to land, ATC received a low altitude alert for N60381. ATC
attempted to advise the pilot to climb immediately, but there was no response. Shortly before
radar contact was lost, data showed decreasing ground speed and a rapid descent. N60381
crashed in a commercial parking lot at an almost nose-down vertical attitude. Most of the aircraft
was destroyed in the post impact fire, and all souls on board were lost.
The purpose of this study is to examine the weather conditions that were present before
and during the time of the incident for N60381, what weather conditions contributed to the loss
of control and crash. This paper is using data from the NTSB accident report for N60381,
CEN20FA075, as well as an NTSB weather study conducted in conjunction with this incident.
Icing is an issue that affects all aircraft, and it is a nearly ever-present danger in aviation. With
the proper knowledge and training, incidents like this can be avoided in the future.
N60381 Accident Case Study 3
Synopsis of Incident
The accident flight for N60381 departed on February 6, 2020, around 1307. The flight
was an IFR flight from Jackson-Hawkins Field Airport, Jackson Mississippi, and was planned to
arrive at Shreveport Regional Airport, Shreveport Louisiana. Departure and climb out were not
recorded in the accident report, so it is reasonable to assume that these phases of flight were
without incident or abnormality.
After climbing to the filed flight plan altitude by about 1336, the accident flight was at
6,000 ft. At 1350 the pilot contacted ATC to inform them that the aircraft was accumulating a
buildup of ice on the wing struts and windshield edges (NTSB, 2022.). Because of the
accumulation of ice on the struts and windshield, the pilot requested a lower altitude of 4,000 ft
in an attempt to reduce or eliminate the ice buildup. ATC approved the flight level change, and
by 1352 the pilot informed ATC that the altitude change did assist with the reduction of ice
buildup and that he would remain at 4,000ft. Shortly after this exchange the pilot requested
another altitude change to 2,000 ft. ATC denied the change to 2,000 ft and informed the pilot that
the lowest altitude that he could be cleared to was 3,000 ft. By 1355 the pilot requested and was
approved for a flight level change to 3,000ft.
By this point in the flight, the pilot realized that the altitude change was not sufficient
enough to reduce the buildup of ice to acceptable levels, and at 1405 the pilot requested a
deviation of flight. The request was to deviate to Ruston Regional Airport (RSN) to remove the
ice from the aircraft. ATC then asked what type of approach the pilot wanted for RSN. The pilot
responded at 1407, requesting an Area Navigation (RNAV) approach for runway 36 at RSN.
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ATC then approved the approach and cleared the pilot direct to the initial approach fix for the
RNAV runway 36, which is RUKOW. The pilot then acknowledged the clearance.
Four minutes later, at 1411, a low altitude alert was given for the accident flight and ATC
attempted to inform the pilot that he was at 1,000 ft and needed to climb immediately. There was
no response from the pilot of the accident flight. Just before radar contact was lost, the data
showed that the aircraft’s ground speed decreased and that it was in a rapid descent. The aircraft
impacted the ground at a near vertical nose-down attitude, and a post-impact fire consumed
much of the aircraft including flight instruments, fuselage, cockpit, cabin, and right wing. The
pilot and 2 passengers all sustained fatal injuries as a result of the impact.
Causation
According to the National Transportation Safety Board regarding the accident involving a
Cessna 182 registration N60381, with a report number of CEN20FA075, the probable cause of
the accident was structural icing. (NTSB, 2022). Since the suspected structural icing was not
visible at the site of the crash due to the post-impact fire and ambient air temperature, the
probable cause was determined by using the pilots reports of icing, weather advisories and
reports current during the time of the accident, and the flight profile before impact. The use of
these components leads to reason that this accident is consistent with a loss of aircraft control
due to in-flight ice buildup. Cold air advection in the region, and temperature inversions are both
strong candidates for being contributing factors in causing this accident. With MVMC and IMC
conditions prevalent throughout the area of the accident, and along the planned flight route
N60381 Accident Case Study 5
supercooled water droplets suspended in the cloud layers were vary likely to form and be the
main contributing factor to cause the buildup of ice on the aircraft
Decision Criteria
As a direct result to the structural icing that was accumulated on the aircraft, coupled with
the loss of pilot control caused by the ice buildup, the aircraft impacted the ground at a near
vertical nose-down attitude, killing all on board. A different, non-fatal incident had similar
characteristics which included ice accumulation on the windshield and wings. NTSB accident
number GAA20CA075, involves a Cessna 182 that accumulated ice in-flight. This aircraft was
operating in IMC, and the pilot noticed a buildup of ice on the wings and windshield. The pilot
requested a diversion to a nearby airport. ATC approved the diversion and approved an
instrument approach. After successfully completing the instrument approach, while the aircraft
was roughly 10 ft above the runway, the aircraft entered a stall and touched down hard on the
runway. (NTSB, 2020.) The findings for this incident were very similar to the findings in the
incident CEN20FA075; flight into icing conditions which resulted in structural icing and an
aerodynamic stall. (NTSB, 2020)
Both of these incidents involved flight into icing conditions, intentional or otherwise.
Both pilots reported icing on the windshield and wings and requested a diversion to correct the
icing issue. Also, the findings in both GAA20CA075 and CEN20FA075 list environmental
issues that were conducive to structural icing as a contributing factor to the incident. The pilots
in both incidents experienced very similar issues, and they were handled in almost identical
ways. It stands to reason that what caused the stall above the runway and resulted in a hard
N60381 Accident Case Study 6
landing in incident GAA20CA075 could also be a major factor in the fatal accident in incident
CEN20FA075. While the outcome of each incident ended differently, the loss of control of
flight, the loss of lift, and an aerodynamic stall all appears to be present in both cases. The only
difference between the two incidents is the altitude and location the stall began, and how the
flight ultimately ended.
Analysis
Flight into icing conditions is an issue that has been present in aviation since the birth of
manned flight. Rulemaking and legislation changes will not eliminate the formation of ice on an
aircraft. There have been many incidents that ice accumulation on the aircraft was the causal
factor. The American Meteorological Society conducted a study focusing on aircraft accidents
where airframe icing was the reason for the crash. The study showed that, between the years of
1982 to 2000, out of all airframe icing accidents, General Aviation (GA) aircraft were
responsible for 80.6% of the accidents (Petty & Floyd, 2004). The study also states that out of
the 819 deaths caused by airframe icing accidents from 1982 to 2000, GA was responsible for
522 deaths (Petty & Floyd, 2004). While GA aircraft are still responsible for the highest amount
of airframe icing incidents at the end year of 2000 in this study, the data does show a steady
decline in airframe icing related accidents from a high of 49 in 1982 to 17 in 2000 (Petty &
Floyd, 2004).
The NTSB conducted a meteorology survey for the area and time of the accident of
N60381; the report used the upper air charts for the region, and reviewed the conditions at 850-
hPa, or 5,000 ft. This is very close to the cruise altitude of the accident aircraft, which was 6,000
ft. The area experienced a wind shift from the southwest at 10 kts, to west-northwest at 30 kts,
N60381 Accident Case Study 7
which accompanied a temperature drop from -2˚C to -8˚C, and indicated a cold air advection
over the region, which is common behind cold fronts (Eick, 2020). This temperature was much
different than what was reported at the departure field of +7˚C only one hour earlier (Eick,
2020). Searching the FAA databases, it showed that the Automated Flight Service Station
(AFSS) did not have any contact with the pilot, nor did any other third-party vendor for weather
data or filing a flight plan. Foreflight was also searched for any activity from the pilot, and none
was found. It is unknown if the pilot used any weather data tools prior to the accident flight for
weather familiarization (NTSB, 2020).
This weather study accessed weather data from NOAA and found that a temperature
inversion layer was present around the time and site of the accident. This temperature inversion
layer was present at the altitudes between 2,600 ft through 5,345 ft (Eick, 2020). A temperature
inversion is a weather theory where the air temperature increases with altitude, instead of
cooling, which would be considered normal. Since the accident aircraft was cruising at 6,000 ft,
and was picking up icing, the standard practice is to reduce the altitude to get into warmer air.
When the pilot descended to 3,000 ft, he was going into colder air, which did not promote ice
reduction. It instead promoted the accumulation of structural icing.
Since the pilot was approved for an IFR approach, it stands to reason that he was
preparing the aircraft for the approach and landing phases of flight. Reduction of airspeed and
altitude are common during these phases. According to the Pilots handbook of Aeronautical
Knowledge, “Pilots should be alert for icing anytime the temperature approaches 0˚C and visible
moisture is present” (PHAK, 2016). Since the conditions during the time of the incident were
IMC/MVMC, and there was a PIREP that reported trace to light rime and mixed ice, a
temperature of -2˚C at 6,000 ft, and clouds reported with bases of 700 ft, and tops at 7,100 ft
N60381 Accident Case Study 8
(Eick, 2020). It can be assumed that the accident aircraft passed through these clouds, and
therefor flew through visible moisture at temperatures at or below 0˚C. Flight through these
weather conditions have a high probability of forming structural icing on an aircraft. It follows
that the airplane flew through icing conditions and that a tailplane stall most likely occurred,
considering that the radar data showed a decrease in groundspeed and a rapid descent (NTSB,
2020).
A tailplane stall can occur when the downforce provided by the horizontal stabilizer is
corrupted with a buildup of ice. “Typically, tailplane stall induced by icing is most likely to
occur near the flap limit speed when the flaps are extended to the landing position, especially
when extension is combined with a nose down pitching maneuver, airspeed change, power
change or flight through turbulence.” (Skybrary, 2022). Since the accident aircraft was beginning
an instrument approach, it is safe to assume that most of these qualifiers were met. As little as ¼-
inch of ice buildup on the leading edge of the wings of an aircraft can increase the stall speed by
25-40 kts, and if the pilot was using autopilot for the accident flight, the buildup of ice on the
airframe and control surfaces could have gone unnoticed because of the constant corrections by
the autopilot (NTSB, 2020). Using the track log from Flightaware, it would appear that the
autopilot was engaged for this flight. Being able to maintain a constant altitude for long periods
of time without vertical deviation while “hand flying” can be a challenge for almost any pilot
even in calm weather. The Flightaware track log shows that N60381 maintained an altitude of
6,000 ft for 21 minutes without interruption before maintaining 6,100 ft for 7 minutes after that
(Flightaware, 2022). Once the autopilot was disengaged, all control corrections were removed,
which could have resulted in an abrupt attitude change, and if there was ice buildup on the
leading edge of the wings, and on the horizontal stabilizer, that rapid change in attitude could
N60381 Accident Case Study 9
have initiated a tailplane stall. A stall like this could explain the reason for the near vertical nose-
down impact. Since there was no downforce produced by the tail, the aircraft was no longer able
to maintain a level flight characteristic, which would cause the nose to drop to an almost vertical
attitude.
Implications
As stated earlier, weather cannot be changed or governed. The problem of ice
accumulation on aircraft can only be mitigated through interaction with things that can be
controlled by people. If the issue of in-flight icing is not addressed any further beyond this point,
it can be expected that valuable knowledge will be missed, and there will be unnecessary loss of
life as a result of this stagnation of research. One such signpost for the need for the continuation
of research to address this issue is in the report, A Statistical Review of Aviation Airframe Icing
Accidents in the U.S. In this report, it can be seen that during this 19-year period, the reduction in
icing related accidents can directly correlate with the causes discovered by the accident
investigations, improved icing analysis, and forecasting techniques (Petty & Floyd, 2004).
Ice buildup is not something that normally remains on an aircraft long after the incident.
It could be removed by the force of the impact, the temperature of the surrounding air, or in
extreme cases, a post-impact fire. Knowing how ice affects flight characteristics on any aircraft
is of a valuable nature. The more that is known on how ice buildup affects the aerodynamics of
an aircraft in any phase of flight allows the FAA to impose more effective regulations, for the
pilots to be more aware of the possibility of icing, and to ultimately conduct a flight in potential
icing conditions as safely as possible.
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The FAA has already implemented several regulations regarding flight in icing
conditions. These regulations can be found under CFR 91.527, and they relate only to flight in
icing conditions (CFR, n.d.). This CFR, in very abbreviated terms, says that a pilot can not fly
into known icing conditions unless the aircraft is rated for operating in icing conditions, and has
approved anti-icing or ice protection equipment installed and operable on the aircraft (CFR,
n.d.).
Recommendations
Icing can form in almost any geographical location, regardless of the temperature on the
ground. Pilots should always be alert for signs of ice accumulation because geographical location
is not an acceptable reason for ignorance. All pilots are required to obtain a weather briefing
prior to a flight, therefore more attention must be paid to the section of the brief that includes any
icing conditions, AIRMETS Zulu or Convective SIGMETS. Being aware of the temperatures at
the planned level of flight will also assist in avoiding any encounters with icing conditions.
(FAA, 2019). The FAA has released an advisory circular 00-45H which has a large amount of
valuable information that is directly related to in-flight icing. All pilots need to take the time to
familiarize themselves with the information contained within that circular because it will be
invaluable when that information is truly needed. Pilots cannot just “go through the motions”
when it comes to a weather briefing. Just because icing is not something that normally appears in
the weather brief, does not mean one should not look for it. Knowing everything that is humanly
possible about the weather before a flight will ensure that every step has been taken to promise
the safest possible flight in the current weather conditions. Pilots must know the limitations of
their aircraft. If the aircraft is not rated to fly in known icing conditions, then it should not be
N60381 Accident Case Study 11
flown in those conditions. If the aircraft is equipped for flight in known icing conditions, the
pilot must know how to properly operate the anti-ice and/or de-icing systems. Delaying the use
of de-icing equipment can have the same outcome as not having any ice protection at all (NTSB,
2020).
Conclusion
The cause of this incident may only have one physical contributor, but there were more
issues that went unnoticed. The apparent lack of an appropriate preflight briefing, the disregard
for a proper weather brief, and the flight into known, and noticed icing conditions with an
aircraft that was not approved for flight in those conditions. Ice is an indiscriminate threat and
does not pick and choose what it adheres to, therefore pilots must be aware of the dangers that
icing conditions present to their flight and their safety. Pilots need to be aware of the threat that
ice can have on a flight, and they must also know how to mitigate the risks safely and properly if
icing is encountered. More research needs to be done involving in-flight icing in order to
continue improving the safety and survivability of air travel.
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References
Advisory Circular 00-45H. Federal Aviation Administration. (2019, March 6). Retrieved August
5, 2022, from https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_00-
45H_CHG_2.pdf
Eick, D. (2020, March 30). NTSB Weather Study for CEN20FA075. NTSB. Retrieved July 20,
2022, from https://www.ntsb.gov/_layouts/NTSB/OpenDocument.aspx?
Document_DataId=9352066&FileName=CEN20FA075+-+Chatham%2C+LA-Rel.pdf
The Federal Register. Code of Federal Regulations. (n.d.). Retrieved August 2, 2022, from
https://www.ecfr.gov/current/title-14/chapter-I/subchapter-F/part-91/subpart-F/section-
91.527
Ice contaminated tailplane stall. SKYbrary Aviation Safety. (2022, June 23). Retrieved August
1, 2022, from https://skybrary.aero/articles/ice-contaminated-tailplane-
stall#:~:text=Typically%2C%20tailplane%20stall%20induced%20by,change%20or
%20flight%20through%20turbulence.
N60381 Flight Tracking and history. FlightAware. (n.d.). Retrieved August 5, 2022, from
https://flightaware.com/live/flight/N60381
NTSB. (2022, April 21). NTSB - Report CEN20FA075. Retrieved July 20, 2022, from
https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/
100910/pdf
NTSB. (2020, January 2). NTSB – Report GAA20CA075. Retrieved July 20, 2022, from
https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/
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Petty, K. R., & Floyd, C. D. (2004, September 17). A STATISTICAL REVIEW OF AVIATION
AIRFRAME ICING ACCIDENTS IN THE U.S. American Meteorological Society.
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Pilot’s handbook of aeronautical knowledge9(2016th ed.). (2016). Aviation Supplies &
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