Preliminary Reports
Ten Killed in Floatplane Crash - De Havilland Canada DHC-3 Otter, Sept. 4, 2022, Freeland, Washington
The pilot and nine passengers were killed when the scheduled Part 135 charter flight abruptly plunged into Mutiny Bay off Whidbey Island, Washington. The accident occurred 19 minutes after the flight’s departure from Friday Harbor with a planned destination of Renton Municipal Airport, both in Washington. FAA flight track data showed that the flight progressed at altitudes between 650 and 975 feet and groundspeeds in the range of 115-125 knots, flying southward and then southeast. At 15:08:43 the floatplane climbed to 1,125 feet while slowing to 109 knots; six seconds later, it had descended to 875 feet at 100 knots. The last position hit was recorded two seconds after that at 700 feet and 55 knots groundspeed.
The pilot joined the operator in 2013 and was one of two qualified in the turbine Otter, which he’d flown since 2017. His make-and-model experience was not disclosed in the NTSB’s preliminary report, but three months earlier he’d logged a total of 4,686 hours of flight experience. The accident occurred on his second circuit of the day, each involving multiple legs. Weather was benign, with 10-knot northwesterly winds and 10 miles visibility beneath a few clouds at 4,000 feet and a 9,500-foot broken layer.
Witnesses reported seeing the airplane flying straight and level before climbing slightly, then entering a near-vertical descent. Several described it as “spinning,” “rotating,” or “spiralling” on its way down. One reported hearing the engine/propeller noise, which did not change before impact. Small pieces of wreckage were recovered from the surface by citizens and local authorities; a sonar search conducted by the Washington Department of Fish and Wildlife, the University of Washington, and the National Oceanic and Atmospheric Administration subsequently located the debris field at a depth of 190 feet. Recovery efforts were complicated by currents and poor visibility, but as of this writing more than two-thirds of the wreckage and the bodies of six of the 10 victims have been retrieved.
Depressurization Suspected in Citation “Ghost Flight” - Cessna 551 Citation II S/P, Sept. 4, 2022, Baltic Sea off of Latvia
The Austrian-registered jet crashed off the coast of Ventspils, Latvia, after overflying its destination on a flight from Spain’s Jerez--La Parra Airport to Cologne, Germany. Four people were reported to be on board. After entering German airspace at FL360 and apparently beginning to maneuver for descent, the pilot stopped responding to air traffic control and the airplane continued on a northeasterly track at a level altitude for another hour and 41 minutes. Press reports indicate that radio contact was lost before the airplane left Spanish airspace, and it was successively shadowed by French, German, and Danish fighter jets. The Danish pilot reported being unable to see anyone in the cockpit but witnessed the Citation spiral into the Baltic Sea after apparently exhausting its fuel supply. Its final rate of descent reached 8,000 feet per minute.
The airplane was certified for single--pilot operation. The passengers included the pilot’s wife, their daughter (also a certificated pilot), and her boyfriend. According to an uncorroborated story in the German newspaper Bild, the pilot reported a problem with the cabin pressurization system shortly after takeoff but continued the flight. The following day Latvian naval forces recovered pieces of debris including some aircraft seats and human remains. On September 8, investigation of the accident was delegated to the German Federal Bureau of Aircraft Accident Investigation (BFU).
Helicopter Pilot Succumbs During Rescue - Eurocopter EC120B, Sept. 11, 2022, Subang, Malaysia
Malaysia’s Transport Minister reported that the solo pilot survived overnight in the wreckage but lost consciousness and died during the evacuation flight the following morning. Air traffic control lost contact with the U.S.-registered helicopter at 12:16 on September 11, about 40 minutes into a planned one-hour flight; radar indicated a sudden loss of altitude. No distress call was received. Search-and-rescue operations involving five different agencies began that afternoon, but had to be suspended due to darkness and poor weather.
The search resumed the following morning, concentrating on a 5-km (3.1-mile) radius around the position of the last radar hit, and located the wreckage in the Chikus Forest Reserve at 8:18. The pilot, a native of Hong Kong, was pinned inside the cockpit but still conscious. There were no initial suggestions about the cause of the accident, now being investigated by the Civil Aviation Authority of Malaysia, but the Perak police chief did state that the initial examination of the site found no evidence of an explosion.
Final Reports
Convective Downdrafts Brought Down Caravan - Cessna 208B, Sept. 16, 2019, Manaus, Amazonas, Brazil
The scheduled passenger/cargo flight crashed just after takeoff, causing serious injuries to one pilot and six passengers and minor injuries to the remaining three passengers and second pilot. Thunderstorms were reported close to the field at the time, and the airport changed status from visual to instrument flight rules due to reduced visibility in heavy rain. The accident was attributed to wind shear or downdrafts from the passing storm front, which led an arriving Airbus A320 and ATR 42 to divert to alternate airports. The ATR 42 crew reported strong winds, turbulence, and heavy rain during their missed approach to Runway 11 prior to diverting. Airport approach and tower controllers did not advise the flight crew of those diversions or of the rapidly changing weather conditions. The pilot-in-command, in turn, reported feeling pressured to keep his flights running on schedule.
Unstable Approach Ended in Low-altitude Stall - Socata TBM700, Oct. 3, 2019, Lansing, Michigan
While the actual crash was attributed to a low-altitude stall during an attempted go-around, the NTSB’s factual report took pains to note that “At no point during the approach did the pilot maintain the airframe manufacturer’s specified approach speed of 85 knots.” Instead, it slowed from 166 knots crossing the final approach fix to 74 knots just before the accident. One passenger survived. Four passengers and the pilot were killed.
The IFR flight from Greenwood, Indiana, was cleared to fly the ILS approach to Runway 10R at Lansing and joined the localizer without difficulty. Half a mile from the threshold at about 180 feet altitude, it entered a shallow climbing left turn, then stalled into the ground. Using the estimated weights of the occupants and a fuel load of 202 gallons (1,374 pounds) computed from fuelling records, investigators also calculated that at takeoff the turboprop was loaded 232 pounds above its certified maximum gross weight, with its center of gravity 2.53 inches aft of limits. After burning about 70 gallons (476 pounds) of fuel en route, it was still 126 pounds over its maximum allowable landing weight with center of gravity 2.95 inches aft of limits at the moment of impact.
The 48-year-old, 1,400-hour commercial pilot had logged 86.2 hours in TBM 700-series airplanes, all during the preceding year. Prevailing weather included calm winds and visibility of 1.25 miles in mist under a 400-foot overcast. The wreckage was found with the landing gear retracted, the flaps halfway between their takeoff and landing positions with the selector up and locked, the spoilers retracted, and the throttle at flight idle. A 2014 safety study of TBM 700 loss-of-control accidents by France’s BEA found that a tendency to roll left when power is increased at low airspeed was aggravated at airspeeds below 70 knots, and that “without corrective rudder input after a rapid application of thrust the airplane tended to roll to the left during an aerodynamic stall.” The reduced stability caused by an aft center of gravity would make stall recovery more difficult.
Wildlife Survey Brought Down by LTE - Bell 206B, Jan. 23, 2022, 23 miles southeast of Camrose, Alberta, Canada
The crash of a wildlife survey flight contracted by the Alberta provincial government has been attributed to a loss of tail rotor effectiveness (LTE), an aerodynamic phenomenon peculiar to helicopters operating at low airspeed in certain unfavorable wind conditions. All four crew members suffered serious injuries and were transported to hospital by rescuers who arrived about one hour after the accident.
The accident occurred on the sixth day of wildlife census flights conducted at about 300 feet above ground level and about 90 knots airspeed. After the spotters identified target species, the pilot would slow the helicopter and descend to enable the observers to count the animals and classify them by size and gender. The crew flew their first survey between 8:46 and 9:22, then repositioned 2.5 nm to the east for a second northbound transect. After the observers spotted animals of interest in low scrub, the pilot made a descending 360-degree turn to facilitate their count. The helicopter had slowed to nine knots groundspeed at an altitude of about 80 feet when it experienced an uncommanded right yaw. The pilot attempted to counter with left pedal but was unable to regain control before the ship struck the ground with little or no forward airspeed, spreading the skids and pushing the rear skid cross tube into the fuel cell. Fuel from the ruptured cell sprayed onto all four occupants.
LTE is a purely aerodynamic phenomenon not associated with any mechanical malfunction. Rather, the combination of high power demand from the main rotor system and wind conditions that reduce the mechanical efficiency of the tail rotor to counteract engine torque lead to an uncontrollable spin. In this case, airspeed below that needed for effective translational lift and a wind direction conducive to both main rotor disc interference and tail rotor vortex ring state (in which tail rotor thrust is reduced by wind passing through in the same direction) were blamed for the loss of yaw control.