North America

The instrument-rated private pilot and passenger departed into instrument meteorological conditions with a 600-ft cloud ceiling in an airplane that was about 550 lbs over gross weight. Air traffic control data showed the airplane in a climbing left turn that continued beyond the assigned heading. After reaching 1,400 ft msl, the airplane continued turning left and its altitude and speed began to vary. The airplane continued in a left spiral, completing more than two full circles, then decelerated in a right turn and rapidly descended until impact with terrain. Examination of the flight control system revealed no evidence of mechanical malfunctions and downloaded engine data indicated normal engine operation. Downloaded data from the autopilot system revealed three in-flight error codes. The first error code, which likely occurred about 1 minute after takeoff, would have resulted in the autopilot, if it was engaged at the time, disengaging. The subsequent error codes likely occurred during the erratic flight profile, with the autopilot disengaged. Before the accident flight, the pilot had informed a mechanic, who is also a pilot, of intermittent issues with the autopilot system and that these issues were unresolved. The mechanic had flown with the accident pilot previously and assessed his instrument flying skills as weak. The flight instructor who provided initial flight training for the turbine engine transition stated the pilot's instrument flying proficiency was poor when he was hand flying the airplane. Toxicology testing revealed that the pilot had used marijuana, and his girlfriend stated the pilot would take a marijuana gummy before bedtime to sleep more soundly. However, given that no psychoactive compounds were found in blood specimens, it is unlikely that the pilot was impaired at the time of the accident. The instrument conditions at the time of the accident, the airplane's erratic flightpath, and the pilot's reported lack of instrument proficiency when flying by hand support the likelihood that the pilot experienced spatial disorientation sometime after takeoff. In addition, given the reports of the intermittently malfunctioning autopilot that had not been fixed, it is likely the pilot experienced an increased workload during a critical phase of flight that, in combination with spatial disorientation, led to the pilot's loss of airplane control.

On February 23, 2019, at 1239 central standard time, Atlas Air Inc. (Atlas) flight 3591, a Boeing 767-375BCF, N1217A, was destroyed after it rapidly descended from an altitude of about 6,000 ft mean sea level (msl) and crashed into a shallow, muddy marsh area of Trinity Bay, Texas, about 41 miles east-southeast of George Bush Intercontinental/Houston Airport (IAH), Houston, Texas. The captain, first officer (FO), and a nonrevenue pilot riding in the jumpseat died. Atlas operated the airplane as a Title 14 Code of Federal Regulations Part 121 domestic cargo flight for Amazon.com Services LLC, and an instrument flight rules flight plan was filed. The flight departed from Miami International Airport (MIA), Miami, Florida, about 1033 (1133 eastern standard time) and was destined for IAH. The accident flight’s departure from MIA, en route cruise, and initial descent toward IAH were uneventful. As the flight descended toward the airport, the flight crew extended the speedbrakes, lowered the slats, and began setting up the flight management computer for the approach. The FO was the pilot flying, the captain was the pilot monitoring, and the autopilot and autothrottle were engaged and remained engaged for the remainder of the flight. Analysis of the available weather information determined that, about 1238:25, the airplane was beginning to penetrate the leading edge of a cold front, within which associated windshear and instrument meteorological conditions (as the flight continued) were likely. Flight data recorder data indicated that, during the time, aircraft load factors consistent with the airplane encountering light turbulence were recorded and, at 1238:31, the airplane’s go-around mode was activated. At the time, the accident flight was about 40 miles from IAH and descending through about 6,300 ft msl toward the target altitude of 3,000 ft msl. This location and phase of flight were inconsistent with any scenario in which a pilot would intentionally select go-around mode, and neither pilot made a go-around callout to indicate intentional activation. Within seconds of go-around mode activation, manual elevator control inputs overrode the autopilot and eventually forced the airplane into a steep dive from which the crew did not recover. Only 32 seconds elapsed between the go-around mode activation and the airplane’s ground impact.

The pilot was conducting a personal cross-country flight with one passenger in his twin-engine airplane. There was no record that the pilot received a weather briefing before the accident flight. While en route to the destination, the pilot was in contact with air traffic control and received visual flight rules flightfollowing services. About 18 miles from the destination airport, the radar service was terminated, as is typical in this geographic region due to insufficient radio and radar coverage below 7,000 ft. The airplane was heading northeast at 4,900 ft mean sea level (msl) (about 2,200 ft above ground level [agl]). About 4 minutes later, radar coverage resumed, and the airplane was 6 miles west of the airport at 4,100 ft msl (1,400 ft agl) and climbing to the north. The airplane climbed through 6,000 ft msl (3,300 ft agl), then began a shallow left turn and climbed to 6,600 ft msl (3,800 ft agl), then began to descend while continuing the shallow left turn ; the last radar data point showed the airplane was about 20 nm northwest of the airport, 5,100 ft msl (2,350 ft agl) on a southwest heading. The final recorded data was about 13 miles northwest of the accident site. A witness near the destination airport heard the pilot on the radio. He reported that the pilot asked about the cloud height and the witness responded that the clouds were 800 to 1,000 ft agl. In his final radio call, the pilot told the witness, "Ok, see you in a little bit." The witness did not see the airplane in the air. The airplane impacted terrain in a slightly nose-low and wings-level attitude with no evidence of forward movement, and a postimpact fire destroyed a majority of the wreckage. The damage to the airplane was consistent with a relatively flat spin to the left at the time of impact. A postaccident examination did not reveal any preimpact mechanical malfunctions or anomalies that would have precluded normal operation. A detailed examination of the cockpit instruments and other portions of the wreckage was not possible due to the fire damage. A cold front had advanced from the northeast and instrument meteorological conditions prevailed across the region surrounding the accident site and the destination airport; the cloud ceilings were 400 ft to 900 ft above ground level. The airplane likely experienced wind shear below 3,000 ft, and there was likely icing in the clouds. While moderate icing conditions were forecast for the accident site, about the time of the accident, investigators were unable to determine the amount and severity of icing the flight may have experienced. The weather conditions had deteriorated over the previous 1 to 2 hours. The conditions at the destination airport had been clear about 2 hours before accident, and visual flight rules conditions about 1 hour before accident, when the pilot departed. Based on the available evidence it is likely that the pilot was unable to maintain control of the airplane, which resulted in an aerodynamic stall and spin into terrain.

According to the first officer, during the first cargo flight of the day, the left engine propeller control was not working properly and the captain indicated that they would shut down the airplane and contact maintenance if the left engine propeller control could not be reset before the return flight. For the return flight, the engines started normally, and both propellers were cycled. The captain and the first officer were able to reset the left propeller control, so the airplane departed with the first officer as the pilot flying. The takeoff and initial climb were normal; however, as the airplane climbed through 4,000 ft, the left engine propeller control stopped working and the power was stuck at 2,400 rpm. The captain tried to adjust the propeller control and inadvertently increased power to 2,700 rpm. The captain then took control of the airplane and tried to stabilize the power on both engines. He leveled the airplane at 4,500 ft, canceled the instrument flight rules flight plan, and flew via visual flight rules direct toward the destination airport. The first officer suggested that they return to the departure airport, but the captain elected to continue as planned (The destination airport was located about 160 nautical miles from the departure airport). The first officer's postaccident statements indicated that he did not challenge the captain's decision. When the flight began the descent to 1,500 ft, the right engine began to surge and lose power. The captain and the first officer performed the engine failure checklist, and the captain feathered the propeller and shut down the engine. Shortly afterward, the left engine began to surge and lose power. The captain told the first officer to declare an emergency. The airplane continued to descend, and the airplane impacted the water "violently," about 32 miles east of the destination airport. The captain was unresponsive after the impact and the first officer was unable to lift the captain from his seat. Because the cockpit was filling rapidly with water, the first officer grabbed the life raft and exited the airplane from where the tail section had separated from the empennage. The first officer did not know what caused both engines to lose power. The airplane was not recovered from the ocean, so examination and testing to determine the cause of the engine failures could not be performed. According to the operator, the flight crew should have landed as soon as practical after the first sign of a mechanical issue. Thus, the crew should have diverted to the closest airport when the left engine propeller control stopped working and not continued the flight toward the destination airport.

On February 6, 2019, about 1530 Pacific standard time, a Piper PA 46-350P, N997MA, was substantially damaged when it was involved in an accident near Aurora, Oregon. The private pilot and flight instructor were seriously injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 instructional flight. The pilot reported that the purpose of the flight was to practice commercial pilot maneuvers. After practicing slow flight, chandelles, lazy eights, and eights on pylons, they returned to the airport and discussed how to conduct a practice a power-off 180° landing as they entered the traffic pattern. When the airplane was abeam the 1,000-foot runway markings, the pilot reduced the power to idle and started a left turn toward the runway. He stated that he realized that the airplane was “probably not going to make the runway” and that the airplane was “not on final course.” He recalled the airplane turning sharply to the left as he was pulled up on the control yoke and added right rudder. He could not recall whether he applied power. The pilot did not report any mechanical malfunctions or anomalies with the airplane. A video of the event showed the airplane in a left turn as it descended toward the runway. The airplane’s left bank decreased to a wings-level attitude before the airplane entered a steeper left bank, followed immediately by a right bank as the airplane descended into the ground short of the runway. The airplane’s right wing and fuselage sustained substantial damage.

The commercial pilot departed for a cross-country, personal flight with no flight plan filed. No evidence was found that the pilot received a preflight weather briefing; therefore, it could not be determined if he checked or received any weather information before or during the accident flight. Visual meteorological conditions existed at the departure airport; however, during the departure climb, the weather transitioned to instrument meteorological conditions (IMC) with precipitation, microburst, and rain showers over the accident area. During the takeoff clearance, the air traffic controller cautioned the pilot about deteriorating weather conditions about 4 miles east of the airport. Radar data showed that, about 5 1/2 minutes after takeoff, the airplane had climbed to about 7,800 ft above ground level before it started a rapid descending right turn and subsequently impacted the ground about 9.6 miles east of the departure airport. Recorded data from the airplane’s Appareo Stratus 2S (portable ADS-B receiver and attitude heading and reference system) revealed that, during the last 15 seconds of the flight, the airplane’s attitude changed erratically with the pitch angle fluctuating between 45° nose-down and 75°nose-up, and the bank angle fluctuating between 170° left and 150° right while descending from 5,500 to 500 ft above ground level, indicative of a loss of airplane control shortly after the airplane entered the clouds. Several witnesses located near the accident site reported seeing the airplane exit the clouds at a high descent rate, followed by airplane parts breaking off. One witness reported that he saw the airplane exit the overcast cloud layer with a nose down pitch of about 60°and remain in that attitude for about 4 to 5 seconds “before initiating a high-speed dive recovery,” at the bottom of which, the airplane began to roll right as the left horizontal stabilizer separated from the airplane, immediately followed by the remaining empennage. He added that the left wing then appeared to shear off near the left engine, followed by the wing igniting. An outdoor home security camera, located about 0.5 mile north-northwest of the accident location, captured the airplane exiting the clouds trailing black smoke and then igniting. Examination of the debris field, airplane component damage patterns, and the fracture surfaces of separated parts revealed that both wings and the one-piece horizontal stabilizer and elevators were separated from the empennage in flight due to overstress, which resulted from excessive air loads. Although the airplane was equipped with an autopilot, the erratic variations in heading and altitude during the last 15 seconds of the flight indicated that the pilot was likely hand-flying the airplane; therefore, he likely induced the excessive air loads while attempting to regain airplane control. Conditions conducive to the development of spatial orientation existed around the time of the in-flight breakup, including restricted visibility and the flight entering IMC. The flight track data was consistent with the known effects of spatial disorientation and a resultant loss of airplane control. Therefore, the pilot likely lost airplane control after inadvertently entering IMC due to spatial disorientation, which resulted in the exceedance of the airplane’s design stress limits and subsequent in-flight breakup. Contributing to accident was the pilot’s improper decision to conduct the flight under visual flight rules despite encountering IMC and continuing the flight when the conditions deteriorated. Toxicology testing on specimens from the pilot detected the presence of delta-9-tetrahydrocanninol (THC) in heart blood, which indicated that the pilot had used marijuana at some point before the flight. Although there is no direct relationship between postmortem blood levels and antemortem effects from THC, it does undergo postmortem redistribution. Therefore, the antemortem THC level was likely lower than detected postmortem level due to postmortem redistribution from use of marijuana days previously, and it is unlikely that the pilot’s use of marijuana contributed to his poor decision-making the day of the accident. The toxicology testing also detected 67 ng/mL of the sedating antihistamine diphenhydramine. Generally, diphenhydramine is expected to cause sedating effects between 25 to 1,120 ng/mL. However, diphenhydramine undergoes postmortem redistribution, and the postmortem heart blood level may increase by about three times. Therefore, the antemortem level of diphenhydramine was likely at or below the lowest level expected to cause significant effects, and thus it is unlikely that the pilot’s use of diphenhydramine contributed to the accident.

At 0851 Mountain Standard Time on 30 January 2019, the Air Tindi Ltd. Beechcraft King Air 200 aircraft (registration C-GTUC, serial number BB-268) departed Yellowknife Airport (CYZF), Northwest Territories, as flight TIN503, on an instrument flight rules flight itinerary to Whatì Airport (CEM3), Northwest Territories, with 2 crew members on board. At 0912, as the aircraft began the approach to CEM3, it departed controlled flight during its initial descent from 12 000 feet above sea level, and impacted terrain approximately 21 nautical miles east-southeast of CEM3, at an elevation of 544 feet above sea level. The Canadian Mission Control Centre received a signal from the aircraft’s 406 MHz emergency locator transmitter and notified the Joint Rescue Coordination Centre in Trenton, Ontario. Search and rescue technicians arrived on site approximately 6 hours after the accident. The 2 flight crew members received fatal injuries on impact. The aircraft was destroyed.

The pilot of the medical transport flight had been cleared by the air traffic controller for the instrument approach and told by ATC to change to the advisory frequency, which the pilot acknowledged. After crossing the initial approach fix on the RNAV approach, the airplane began a gradual descent and continued northeast towards the intermediate fix. Before reaching the intermediate fix, the airplane entered a right turn and began a rapid descent, losing about 2,575 ft of altitude in 14 seconds; radar returns were then lost. A witness at the destination airport, who was scheduled to meet the accident airplane, observed the pilot-controlled runway lights illuminate. When the airplane failed to arrive, she contacted the company to inquire about the overdue airplane. The following day, debris was found floating on the surface of the ocean. About 48 days later, after an extensive underwater search, the heavily fragmented wreckage was located on the ocean floor at a depth of about 500 ft. A postaccident examination of the engines revealed contact signatures consistent with the engines developing power at the time of impact and no evidence of mechanical malfunctions or failures that would have precluded normal operation. A postaccident examination of the airframe revealed about a 10° asymmetric flap condition; however, significant impact damage was present to the flap actuator flex drive cables and flap actuators, indicating the flap actuator measurements were likely not a reliable source of preimpact flap settings. In addition, it is unlikely that a 10° asymmetric flap condition would result in a loss of control. The airplane was equipped with a total of 5 seats and 5 restraints. Of the three restraints recovered, none were buckled. The unbuckled restraints could suggest an emergency that required crewmembers to be up and moving about the cabin; however, the reason for the unbuckled restraints could not be confirmed. While the known circumstances of the accident are consistent with a loss of control event, the factual information available was limited because the wreckage in its entirety was not recovered, the CVR recording did not contain the accident flight, no non-volatile memory was recovered from the accident airplane, and no autopsy or toxicology of the pilot could be performed; therefore, the reason for the loss of control could not be determined. Due to the limited factual information that was available, without a working CVR there is little we know about this accident.

The two pilots departed in a turbine powered DC-3C at maximum gross weight for a repositioning flight. The airplane was part of a test program for new, higher horsepower engine installation. Soon after liftoff and about 3 seconds after decision speed (V1), the left engine lost total power. The propeller began to auto-feather but stopped feathering about 3 seconds after the power loss. The airplane yawed and banked to the left, descended, and impacted terrain. Recorded engine data indicated the power loss was due to an engine flameout; however, examination of the engine did not determine a reason for the flameout or the auto-feather system interruption. While it is plausible that an air pocket developed in the fuel system during the refueling just before the flight, this scenario was not able to be tested or confirmed. It is possible that the auto-feather system interruption would have occurred if the left power lever was manually retarded during the auto-feather sequence. The power loss and auto-feather system interruption occurred during a critical, time-sensitive phase of flight since the airplane was at low altitude and below minimum controllable airspeed (Vmc). The acutely transitional phase of flight would have challenged the pilots' ability to manually feather the propeller quickly and accurately. The time available for the crew to respond to the unexpected event was likely less than needed to recognize the problem and take this necessary action – even as an immediate action checklist/memory item.

The pilot, copilot, flight attendant, and six passengers departed on a corporate flight to a private airstrip. After leveling off at flight level 280, the flight crew checked the weather conditions at nearby airports. Based on the weather information that they had, the pilot planned for a visual approach to the runway. As the airplane neared the destination, the pilot flew over the runway and entered a left downwind visual traffic pattern to check if any animals were on the runway and what the windsock on the airstrip indicated. The pilot stated that they did not see the windsock as they passed over the runway. The pilot reported that there were turbulence and wind gusts from the hills below and to the west. When the airplane was over the runway about 50 ft above ground level (agl), the pilot reduced the engine power to idle. The pilot reported the airplane then encountered wind shear; the airspeed dropped rapidly, and the airplane was "forced down" to the runway. A representative at the airstrip reported that the airplane hit hard on landing. The pilot unlocked the thrust reversers, applied brakes, and reached to deploy the ground spoilers. As he deployed the thrust reversers, the pilot said it felt like the right landing gear collapsed. He applied full left rudder and aileron, but the airplane continued to veer to the right. The pilot tried using the tiller to steer to the left but got no response. The airplane left the side of the runway and went into the grass, which resulted in substantial damage; the right main landing gear was broken aft and collapsed under the right wing. Postaccident examinations of the airplane revealed no preimpact mechanical malfunctions or failures that would have precluded normal operation. A review of weather conditions showed surface winds out of the north to northwest at 15 kts, with some gusts up to 20 kts. There was potential for turbulence and wind shear below 5,000 ft, but there were no direct observations. The area forecast about 30 minutes after the accident called for northwesterly winds at 10 to 17 kts with a few higher gusts in the afternoon for the general area. Data from an onboard enhanced ground proximity warning system (EGPWS) revealed that the crew received a terrain alert just before the airplane crossed the runway threshold. At the time the airplane was over the runway threshold, it was 48 ft agl and in a 1,391 ft per minute rate of descent. The airplane impacted the runway 3 seconds later. Given the pilot's account, the weather information for the area, and the data from the airplane's EGPWS, it is likely that the airplane encountered wind shear while transitioning from approach to landing.