Crash of a Cessna 414A Chancellor in Colonia: 1 killed

Date & Time: Oct 29, 2019 at 1058 LT
Type of aircraft:
Registration:
N959MJ
Flight Type:
Survivors:
No
Site:
Schedule:
Leesburg - Linden
MSN:
414A-0471
YOM:
1980
Crew on board:
1
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
1
Captain / Total flying hours:
7173
Captain / Total hours on type:
1384.00
Aircraft flight hours:
7712
Circumstances:
The pilot was conducting a GPS circling instrument approach in instrument meteorological conditions to an airport with which he was familiar. During the final minute of the flight, the airplane descended to and leveled off near the minimum descent altitude (MDA) of about 600 ft mean sea level (msl). During this time, the airplane’s groundspeed slowed from about 90 knots to a low of 65 knots. In the few seconds after reaching 65 knots groundspeed, the flight track abruptly turned left off course and the airplane rapidly descended. The final radar point was recorded at 200 ft msl less than 1/10 mile from the accident site. Two home surveillance cameras captured the final few seconds of the flight. The first showed the airplane in a shallow left bank that rapidly increased until the airplane descended in a steep left bank out of camera view below a line of trees. The second video captured the final 4 seconds of the flight; the airplane entered the camera view already in a steep left bank near treetop level, and continued to roll to the left, descending out of view. Both videos showed the airplane flying below an overcast cloud ceiling, and engine noise was audible until the sound of impact. Postaccident examination of the airplane revealed no evidence of preimpact mechanical malfunctions that would have precluded normal operation. The propeller signatures, witness impact marks, audio recordings, and witness statements were all consistent with the engines producing power at the time of impact. The pilot likely encountered restricted visibility of about 2 statute miles with mist and ceilings about 700 ft msl. When the airplane deviated from the final approach course and descended below the MDA, the destination airport remained 3.5 statute miles to the northeast. Although the airplane was observed to be flying below the overcast cloud layer, given the restricted visibility, it is likely that the pilot was unable to visually identify the airport or runway environment at any point during the approach. According to airplane flight manual supplements, the stall speed likely varied from 76 to 67 knots indicated airspeed. The exact weight and balance and configuration of the airplane could not be determined. Based upon surveillance video, witness accounts, and automatic dependent surveillance-broadcast data, it is likely that, as the pilot leveled off the airplane near the MDA, the airspeed decayed below the aerodynamic stall speed, and the airplane entered an aerodynamic stall and spin from which the pilot was unable to recover. Based on a readout of the pilot’s cardiac monitoring device and autopsy findings, while the pilot had a remote history of arrhythmia, sudden incapacitation was not a factor in this accident. Autopsy findings suggested that the pilot’s traumatic injuries were not immediately fatal; soot material in both the upper and lower airways provided evidence that the pilot inhaled smoke. This autopsy evidence supports that the pilot’s elevated carboxyhemoglobin level was from smoke inhalation during the postcrash fire. In addition, there were no distress calls received from the pilot and there was no evidence found that would indicate there was an in-flight fire. Thus, carbon monoxide exposure, as determined by the carboxyhemoglobin level, was not a contributing factor to the accident.
Probable cause:
The pilot’s failure to maintain airspeed during a circling instrument approach procedure, which resulted in an exceedance of the airplane’s critical angle of attack and an aerodynamic stall and spin.
Final Report:

Crash of a De Havilland DHC-3 Otter off Little Grand Rapids: 3 killed

Date & Time: Oct 26, 2019 at 0845 LT
Type of aircraft:
Operator:
Registration:
C-GBTU
Survivors:
No
Schedule:
Bissett - Little Grand Rapids
MSN:
209
YOM:
1957
Country:
Crew on board:
1
Crew fatalities:
Pax on board:
2
Pax fatalities:
Other fatalities:
Total fatalities:
3
Captain / Total flying hours:
9500
Captain / Total hours on type:
5800.00
Aircraft flight hours:
16474
Circumstances:
At approximately 0745 Central Daylight Time on 26 October 2019, the Blue Water Aviation float-equipped deHavillandDHC-3 Otteraircraft (registration C-GBTU, serial number 209) departed Bissett Water Aerodrome, Manitoba, with the pilot, 2 passengers, and approximately 800 pounds of freight on board. The destination was Little Grand Rapids, Manitoba, on the eastern shore of Family Lake. At approximately 0845, while on approach to Family Lake, the aircraft’s right wing separated from the fuselage. The aircraft then entered a nose-down attitudeand struck the water surface of the lake. The pilot and the 2 passengers were fatally injured. The aircraft was destroyed by impact forces. The emergency locator transmitter activated momentarily.
Probable cause:
Findings as to causes and contributing factors:
These are conditions, acts or safety deficiencies that were found to have caused or contributed to this occurrence.
1. A fatigue fracture originated in the bolt hole bore of the right-hand wing lift strut’s upper outboard lug plate, and eventually led to an overstress fracture of the right-hand wing lift strut’s upper outboard and inboard lug plates during the left turn prior to the final approach.
2. The failure of the outboard and inboard lug plates led to the separation of the righthand wing lift strut from the wing and, subsequently, the separation of the right wing from the aircraft.

Findings as to risk:
These are conditions, unsafe acts or safety deficiencies that were found not to be a factor in this occurrence but could have adverse consequences in future occurrences.
1. If operational flight plans data and load calculations are not available, there is a risk that, in the event of a missing aircraft or accident, aircraft information, including its number of occupants, route, cargo, and weight and balance information, will not be available for search and rescue operations or accident investigation.

Other findings:
These items could enhance safety, resolve an issue of controversy, or provide a data point for future safety studies.
1. The detailed visual inspection prescribed in the Viking Air Ltd. Supplementary Inspection and Corrosion Control Manual, and required by Airworthiness DirectiveCF2018-4, did not identify cracks that could form in the right-hand wing strut’s upper outboard lug plate.
Final Report:

Crash of a Saab 2000 in Unalaska: 1 killed

Date & Time: Oct 17, 2019 at 1740 LT
Type of aircraft:
Operator:
Registration:
N686PA
Survivors:
Yes
Schedule:
Anchorage - Unalaska
MSN:
017
YOM:
1995
Flight number:
AS3296
Crew on board:
3
Crew fatalities:
Pax on board:
39
Pax fatalities:
Other fatalities:
Total fatalities:
1
Captain / Total flying hours:
14761
Captain / Total hours on type:
131.00
Copilot / Total flying hours:
1447
Copilot / Total hours on type:
138
Aircraft flight hours:
12617
Aircraft flight cycles:
9455
Circumstances:
On October 17, 2019, a Saab SA-2000 airplane, operated by Peninsula Aviation Services Inc. d.b.a. PenAir flight 3296, overran the end of runway 13 at Unalaska Airport (DUT), Unalaska, Alaska. The flight crew executed a go-around during the first approach to runway 13; the airplane then entered the traffic pattern for a second landing attempt on the same runway. Shortly before landing, the flight crew learned that the wind at midfield was from 300° at 24 knots, indicating that a significant tailwind would be present during the landing. Because an airplane requires more runway length to decelerate and stop when a tailwind is present during landing, a landing in the opposite direction (on runway 31) would have favored the wind at the time. However, the flight crew continued with the plan to land on runway 13. Our postaccident calculations showed that, when the airplane touched down on the runway, the tailwind was 15 knots. The captain reported after the accident that the initial braking action after touchdown was normal but that, as the airplane traveled down the runway, the airplane had “zero braking” despite the application of maximum brakes. The airplane subsequently overran the end of the runway and the adjacent 300-ft runway safety area (RSA), which was designed to reduce airplane damage during an overrun, and came to rest beyond the airport property. The airplane was substantially damaged during the runway overrun; as a result, of the 3 crewmembers and 39 passengers aboard, 1 passenger sustained fatal injuries, and 1 passenger sustained serious injuries. Eight passengers sustained minor injuries, most of which occurred during the evacuation. The crewmembers and 29 passengers were not injured.
Probable cause:
The National Transportation Safety Board determines that the probable cause of this accident was the landing gear manufacturer’s incorrect wiring of the wheel speed transducer harnesses on the left main landing gear during overhaul. The incorrect wiring caused the antiskid system not to function as intended, resulting in the failure of the left outboard tire and a significant loss of the airplane’s braking ability, which led to the runway overrun.
Contributing to the accident were
1) Saab’s design of the wheel speed transducer wire harnesses, which did not consider and protect against human error during maintenance;
2) the Federal Aviation Administration’s lack of consideration of the runway safety area dimensions at Unalaska Airport during the authorization process that allowed the Saab 2000 to operate at the airport; and
3) the flight crewmembers’ inappropriate decision, due to their plan continuation bias, to land on a runway with a reported tailwind that exceeded the airplane manufacturer’s limit. The safety margin was further reduced because of PenAir’s failure to correctly apply its company-designated pilot-incommand airport qualification policy, which allowed the accident captain to operate at one of the most challenging airports in PenAir’s route system with limited experience at the airport and in the Saab 2000 airplane.
Final Report:

Crash of a Socata TBM-850 in Breckenridge

Date & Time: Oct 14, 2019 at 1245 LT
Type of aircraft:
Operator:
Registration:
N850NK
Flight Type:
Survivors:
Yes
Schedule:
San Angelo - Breckenridge
MSN:
432
YOM:
2007
Crew on board:
1
Crew fatalities:
Pax on board:
1
Pax fatalities:
Other fatalities:
Total fatalities:
0
Captain / Total flying hours:
8195
Captain / Total hours on type:
6.00
Aircraft flight hours:
2878
Circumstances:
The pilot reported that, during the approach and while the airplane was about 500 ft above ground level and 81 knots, he "felt the descent rate increase significantly." The pilot increased engine power, but "the high rate of descent continued," and he then increased the engine power further. A slow left roll developed, and he applied full right aileron and full right rudder to arrest the left roll. He also reduced the engine power, and the left roll stopped. The pilot regained control of the airplane, but the airplane's heading was 45° left of the runway heading, and the airplane impacted trees and then terrain. The airplane caught fire, and the pilot and passenger exited through the emergency exit. The airplane sustained substantial damage to the windscreens and fuselage. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.
Probable cause:
The pilot's failure to maintain bank control and adequate altitude during the approach, which resulted in his failure to maintain the runway heading and a subsequent collision with trees and terrain.
Final Report:

Crash of a Piper PA-60-602P in Kokomo: 1 killed

Date & Time: Oct 5, 2019 at 1637 LT
Operator:
Registration:
N326CW
Flight Phase:
Flight Type:
Survivors:
No
Schedule:
Kokomo - Kokomo
MSN:
60-0869-8165008
YOM:
1981
Location:
Crew on board:
1
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
1
Captain / Total flying hours:
7500
Aircraft flight hours:
3002
Circumstances:
The airline transport pilot arrived at the departure airport in the reciprocating engine-powered airplane where it was fueled with Jet A jet fuel by an airport employee/line service technician. A witness stated that she saw a "low flying" airplane flying from north to south. The airplane made a "sharp left turn" to the east. The left wing "dipped low" and she then lost sight of the airplane, but when she approached the intersection near the accident site, she saw the airplane on the ground. The airplane impacted a field that had dry, level, and hard features conducive for an off-airport landing, and the airplane was destroyed. The wreckage path length and impact damage to the airplane were consistent with an accelerated stall. Postaccident examination of the airplane found Jet A jet fuel in the airplane fuel system and evidence of detonation in both engines from the use of Jet A and not the required 100 low lead fuel. Use of Jet A rather than 100 low lead fuel in an engine would result in detonation in the cylinders and lead to damage and a catastrophic engine failure. According to the Airplane Flying Handbook, the pilot should witness refueling to ensure that the correct fuel and quantity is dispensed into the airplane and that any caps and cowls are properly secured after refueling.
Probable cause:
The pilot's exceedance of the airplane’s critical angle of attack following a dual engine power loss caused by the line service technician fueling the airplane with the wrong fuel, which resulted in an aerodynamic stall and subsequent loss of control. Contributing was the pilot's inadequate supervision of the fuel servicing.
Final Report:

Crash of a Socata TBM-700 in Lansing: 5 killed

Date & Time: Oct 3, 2019 at 0858 LT
Type of aircraft:
Operator:
Registration:
N700AQ
Flight Type:
Survivors:
Yes
Schedule:
Indianapolis - Lansing
MSN:
252
YOM:
2003
Crew on board:
1
Crew fatalities:
Pax on board:
5
Pax fatalities:
Other fatalities:
Total fatalities:
5
Captain / Total flying hours:
1404
Captain / Total hours on type:
76.00
Aircraft flight hours:
3550
Circumstances:
The pilot was conducting an instrument approach at the conclusion of a cross-country flight when the airplane entered a shallow climb and left turn away from the runway heading about 0.5-mile from the intended runway. According to airspeeds calculated from automatic dependent surveillance-broadcast position data, the airplane’s calibrated airspeed was 166 knots when it crossed over the final approach fix inbound toward the runway and was about 84 knots when it was on a 0.5-mile final approach. The airplane continued to decelerate to 74 knots while it was in a shallow climb and left turn away from the runway heading. At no point during the approach did the pilot maintain the airframe manufacturer’s specified approach speed of 85 knots. The airplane impacted the ground in an open grass field located to the left of the extended runway centerline. The airplane was substantially damaged when it impacted terrain in a wings level attitude. The postaccident examination did not reveal any anomalies that would have precluded normal operation of the airplane. The altitude and airspeed trends during the final moments of the flight were consistent with the airplane entering an aerodynamic stall at a low altitude. Based on the configuration of the airplane at the accident site, the pilot likely was retracting the landing gear and flaps for a go around when the airplane entered the aerodynamic stall. The airplane was operating above the maximum landing weight, and past the aft center-of-gravity limit at the time of the accident which can render the airplane unstable and difficult to recover from an aerodynamic stall. Additionally, without a timely corrective rudder input, the airplane tends to roll left after a rapid application of thrust at airspeeds less than 70 knots, including during aerodynamic stalls. Although an increase in thrust is required for a go around, the investigation was unable to determine how rapidly the pilot increased thrust, or if a torque-roll occurred during the aerodynamic stall.
Probable cause:
The pilot’s failure to maintain airspeed during final approach, which resulted in a loss of control and an aerodynamic stall at a low altitude, and his decision to operate the airplane outside of the approved weight and balance envelope.
Final Report:

Crash of a Boeing B-17G-30-BO Flying Fortress in Windsor Locks: 7 killed

Date & Time: Oct 2, 2019 at 0953 LT
Operator:
Registration:
N93012
Flight Type:
Survivors:
Yes
Schedule:
Windsor Locks - Windsor Locks
MSN:
7023
YOM:
1942
Crew on board:
3
Crew fatalities:
Pax on board:
10
Pax fatalities:
Other fatalities:
Total fatalities:
7
Captain / Total flying hours:
14500
Captain / Total hours on type:
7300.00
Copilot / Total flying hours:
22000
Copilot / Total hours on type:
23
Aircraft flight hours:
11388
Circumstances:
The vintage, former US military bomber airplane was on a tour that allowed members of the public to purchase an excursion aboard the airplane for an LHFE flight. The accident flight was the airplane’s first flight of the day. During the initial climb, one of the pilots retracted the landing gear, and the crew chief/flight engineer (referred to as the loadmaster) left the cockpit to inform the passengers that they could leave their seats and walk around the airplane. One of the pilots reported to air traffic control that the airplane needed to return to the airport because of a rough magneto. At that time, the airplane was at an altitude of about 600 ft above ground level (agl) on the right crosswind leg of the airport traffic pattern for runway 6. The approach controller asked the pilot if he needed any assistance, to which the pilot replied, “negative.” When the loadmaster returned to the cockpit, he realized that the airplane was no longer climbing, and the pilot, realizing the same, instructed the copilot to extend the landing gear, which he did. The loadmaster left the cockpit to instruct the passengers to return to their seats and fasten their seat belts. When the loadmaster returned again to the cockpit, the pilot stated that the No. 4 engine was losing power; the pilot then shut down that engine and feathered the propeller without any further coordination or discussion. When the airplane was at an altitude of about 400 ft agl, it was on a midfield right downwind leg for runway 6. Witness video showed that the landing gear had already been extended by that time, even though the airplane still had about 2.7 nautical miles to fly in the traffic pattern before reaching the runway 6 threshold. During final approach, the airplane struck the runway 6 approach lights in a right-wing-down attitude about 1,000 ft before the runway and then contacted the ground about 500 ft before the runway. After landing short of the runway, the airplane traveled onto the right edge of the runway threshold and continued to veer to the right. The airplane collided with vehicles and a deicing fluid tank before coming to rest upright about 940 ft to the right of the runway. A postcrash fire ensued. Both pilots and five passengers were killed and all six other occupants as well as one people on the ground were injured, five seriously.
Probable cause:
The pilot’s failure to properly manage the airplane’s configuration and airspeed after he shut down the No. 4 engine following its partial loss of power during the initial climb. Contributing to the accident was the pilot/maintenance director’s inadequate maintenance while the airplane was on tour, which resulted in the partial loss of power to the Nos. 3 and 4 engines; the Collings Foundation’s ineffective safety management system (SMS), which failed to identify and mitigate safety risks; and the Federal Aviation Administration’s inadequate oversight of the Collings Foundation’s SMS.
Final Report:

Crash of a Cessna 421A Golden Eagle I in DeLand: 3 killed

Date & Time: Sep 29, 2019 at 1600 LT
Type of aircraft:
Operator:
Registration:
N731PF
Flight Phase:
Flight Type:
Survivors:
No
Schedule:
DeLand - DeLand
MSN:
421A-0164
YOM:
1968
Location:
Crew on board:
1
Crew fatalities:
Pax on board:
2
Pax fatalities:
Other fatalities:
Total fatalities:
3
Captain / Total flying hours:
500
Captain / Total hours on type:
0.00
Aircraft flight hours:
858
Circumstances:
The owner of the airplane had purchased the airplane with the intent to resell it after repairs had been made. As part of that process, a mechanic hired by the owner had assessed the airplane’s condition, proposed the necessary repairs to the airplane’s owner, and had identified a pilot who would, once the repairs and required inspection annual inspection had been completed, fly the airplane from where it was located to where the owner resided. While the mechanic had identified a potential pilot for the relocation flight, he had not yet completed the repairs to the airplane, nor had he completed the necessary logbook entries that would have returned the airplane to service. The pilot-rated passenger onboard the airplane for the accident flight, was the pilot who had been identified by the mechanic for the relocation flight. Review of the pilot-rated passenger’s flight experience revealed that he did not possess the necessary pilot certificate rating, nor did he have the flight experience necessary to act as pilot-in-command of the complex, highperformance, pressurized, multi-engine airplane. Additionally, the owner of the airplane had not given the pilot-rated-passenger, or anyone else, permission to fly the airplane. The reason for, and the circumstances under which the pilot-rated passenger and the commercial pilot (who did hold a multi-engine rating) were flying the airplane on the accident flight could not be definitively determined, although because another passenger was onboard the airplane, it is most likely that the accident flight was personal in nature. Given the commercial pilot’s previous flight experience, it is also likely that he was acting as pilot-in-command for the flight. One witness said that he heard the airplane’s engines backfiring as it flew overhead, while another witness located about 1 mile from the accident site heard the accident airplane flying overhead. The second witness said that both engines were running, but they seemed to be running at idle and that the flaps and landing gear were retracted. The witness saw the airplane roll to the left three times before descending below the tree line. As the airplane descended toward the ground, the witness heard the engines make “two pop” sounds. The airplane impacted a wooded area about 4 miles from the departure airport, and the wreckage path through the trees was only about 75-feet long. While the witnesses described the airplane’s engines backfiring or popping before the accident, the postaccident examination of the wreckage revealed no evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation. Additionally, examination of both propeller blades showed evidence of low rotational energy at impact, and that neither propeller had been feathered in flight. Given the witness statement describing the airplane “rolling three times” before it descended from view toward the ground, it is most likely that the pilot lost control of the airplane and while maneuvering. It is also likely that the pilot’s lack of any documented previous training or flight experience in the accident airplane make and model contributed to his inability to maintain control of the airplane. Toxicology testing was performed on the pilot’s chest cavity blood. The results identified 6.7 ng/ml of delta-9-tetrahydracannabinol (THC, the active compound in marijuana) as well as 2.6 ng/ml of its active metabolite, 11-hydroxy-THC and 41.3 ng/ml of its inactive metabolite delta9-carboxy-THC. Because the measured THC levels were from cavity blood, it was not possible to determine when the pilot last used marijuana or whether he was impaired by it at the time of the flight. As a result, it could not be determined whether effects from the pilot’s use of marijuana contributed to the accident circumstances.
Probable cause:
The pilot’s failure to maintain control of the airplane, which resulted in a collision with terrain. Contributing was the pilot’s lack of training and experience in the accident airplane make and model.
Final Report:

Crash of a Piper PA-46-350P Malibu Mirage off Boothville

Date & Time: Sep 15, 2019 at 1146 LT
Operator:
Registration:
N218MW
Flight Phase:
Flight Type:
Survivors:
Yes
Schedule:
Titusville – Ozona – Santee
MSN:
46-36470
YOM:
2010
Crew on board:
1
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
0
Captain / Total flying hours:
3500
Captain / Total hours on type:
2000.00
Aircraft flight hours:
1116
Circumstances:
On September 15, 2019, at 1146 central daylight time, a Piper PA-46-350P, N218MW, lost engine power while maneuvering over the Gulf of Mexico, and the pilot was forced to ditch. The private pilot was not injured. The airplane was registered to and operated by Mailworks, Inc., Spring Valley, California, under Title 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions existed near the accident site at the time of the accident, and the flight was operated on a visual flight rules flight plan. The flight originated at 0830 eastern daylight time from Space Coast Regional Airport (TIX), Titusville, Florida, and was en route to Ozona Municipal Airport (OZA), Ozona, Texas. His final destination was Gillespie Field Airport (SEE), El Cajon, California. According to the pilot's accident report, he departed TIX with 140 gallons of fuel. After crossing Gulfport (GPT), Mississippi's Terminal Radar Service Area (TRSA) at 10,500 ft, he initiated a slow descent over Boothville, Louisiana, and proceeded southbound towards the mouth of the Mississippi River, descending to 1,500 ft. He then configured the airplane for climb. The engine did not respond to the application of power and the airplane began losing altitude. After going through the emergency checklist, he was unable to restore engine power, and declared an emergency to Houston air route traffic control center (ARTCC) and on frequency 121.5 mHz. He also activated the emergency locator transmitter (ELT) prior to ditching. After ditching, the pilot put on his life jacket, exited the airplane, and remained on its wing until it sank. About an hour later, a U.S. Coast Guard helicopter rescued the pilot and transported him to a hospital in New Orleans, Louisiana. He was discharged a few hours later. The airplane has not been recovered.
Probable cause:
A loss of engine power for undetermined reasons.
Final Report:

Crash of a Convair CV-440F in Toledo: 2 killed

Date & Time: Sep 11, 2019 at 0239 LT
Registration:
N24DR
Flight Type:
Survivors:
No
Schedule:
Millington-Memphis - Toledo
MSN:
393
YOM:
1957
Crew on board:
2
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
2
Captain / Total flying hours:
8000
Copilot / Total flying hours:
11287
Aircraft flight hours:
47742
Circumstances:
The accident occurred during the second of a two-leg nonscheduled cargo flight. The initial leg of the flight departed the preceding evening. The pilots landed about 3.5 hours later for fuel and departed on the accident flight an hour after refueling. The flight entered a cruise descent about 39 miles from the destination airport in preparation for approach and landing. The pilots reported to air traffic control that they were executing a wide base and were subsequently cleared for a visual approach and landing. The landing clearance was acknowledged, and no further communications were received. No problems or anomalies were reported during the flight. The airplane was briefly established on final approach before radar contact was lost. The airplane impacted trees and terrain about 0.5 mile short of the runway and came to rest in a trucking company parking lot. A postimpact fire ensued. Damage to the landing gear indicated that it was extended at the time of impact. The position of the wing flaps could not be determined. Disparities in the propeller blade angles at impact were likely due to the airplane’s encounter with the wooded area and the impact sequence. No evidence of mechanical anomalies related to the airframe, engines, or propellers was observed. A review of air traffic control radar data revealed that the airplane airspeed decayed to about 70 to 75 kts on final approach which was at or below the documented aerodynamic stall speed of the airplane in the landing configuration. Although there was limited information about the flight crew’s schedules, their performance was likely impaired by fatigue resulting from both the total duration of the overnight flights and the approach being conducted in the window of the circadian low. This likely resulted in the flight crew’s failure to maintain airspeed and recognize the impending aerodynamic stall conditions.
Probable cause:
The flight crew’s failure to maintain the proper airspeed on final approach, which resulted in an inadvertent aerodynamic stall and impact with trees, and terrain. Contributing to the accident was the flight crew’s fatigue due to the overnight flight schedule.
Final Report: