Preliminary Reports
Training Accident Claims Two, Beech C99, Aug. 22, 2023, Litchfield, Maine
A newly hired pilot and the company instructor conducting his third initiation flight perished when the 1982-model aircraft abruptly crashed into a stand of 50-foot oak trees. ADS-B data showed that the twin-engine turboprop took off from Maine’s Auburn/Lewiston Municipal Airport (KLEW) at about 17:08 local time, flew the ILS approach to KLEW’s Runway 04, and initiated a missed approach. After reaching the missed approach fix, the flight began the charted left holding pattern, then entered a sudden descent.
A pilot-rated witness saw an airplane he recognized as a Beech 99 flying north and described its engines as sounding “very smooth.” When he looked up again, the airplane was in a “steep dive” with its wings level. Its engines still sounded smooth and its flight path did not change. Shortly after it disappeared behind the trees, he heard a “loud boom.”
The tree strikes at the accident site suggested that it was pitched 20 degrees nose-down and banked 10 degrees right on impact. The debris path measured 424 feet long and 100 feet wide; there was no post-crash fire. At 17:56, KLEW reported clear skies, 10 miles visibility, and 10-knot north winds.
EMS Flight Crashes into Apartments, Eurocopter EC135T1, Aug. 28, 2023, Pompano Beach, Florida
En route to pick up a patient at the scene of an automobile accident, a Broward County Sheriff’s Office helicopter crashed onto the roof of an apartment complex, killing a paramedic onboard and one resident of the building. A second paramedic suffered serious injuries, while the pilot’s injuries were classified as minor.
The pilot reported that during initial climb westward from the Pompano Beach Airpark, he heard a loud “bang” from the rear of the aircraft and saw that the number one engine’s turbine outlet temperature was spiking. The helicopter was then 300-400 feet agl. He set the number one engine to idle power, declared an emergency, and turned back towards the airport. Seeing that the number one engine’s fire warning had illuminated, he activated its fire-suppression system, but the temperature continued to rise.
After a second bang, the pilot lost control of the helicopter, which spun down into the building. A post-crash fire consumed most of the airframe. Video footage supplied by a witness showed “an in-flight fire near the area of the engine exhaust and the tailboom attach point. The tailboom partially separated in-flight and the helicopter descended in a right spin.” The tailboom came to rest about 30 feet from the main wreckage with the Fenestron tail rotor intact. The 1999-model helicopter had flown about 24 hours since its most recent inspection.
Fourteen Killed on Brazilian Charter Flight, Embraer EMB-110P1 Bandeirante, Sept. 16, 2023, Barcelos Airport, Amazonas, Brazil
Both pilots and all 12 passengers died when their charter flight crashed attempting to land at the Barcelos Airport in heavy rain. Initial reports suggested the twin-engine turboprop ran off the end of the runway and through the airport’s perimeter fence, and then struck an embankment. The passengers, all male, are believed to have been on a sport-fishing trip to the Rio Negro.
Final Reports
Design and Certification Inadequacies Cited in Leicester Disaster, Leonardo AW169, Oct. 27, 2018, Leicester, UK
The UK's Air Accidents Investigation Branch (AAIB) concluded that multiple deficiencies in the design, testing, and certification requirements for critical components contributed to the failure of the tail rotor duplex bearing, causing a catastrophic loss of yaw control.
The pilot and all four passengers were killed when the helicopter crashed seconds after taking off from the center of the pitch in King Power Stadium, igniting a fire that quickly engulfed the fuselage. The helicopter was beginning its transition to forward flight at an altitude of 250 feet when an uncontrollable right yaw sent it spinning down onto “a stepped concrete surface.”
Investigators found that the tail rotor duplex bearing had seized, allowing the pitch angle of the tail rotor blades to move to “their physical limit of travel,” amplifying the unopposed torque applied by the main rotor system.
The seizure was attributed to lubrication failure resulting from “a combination of dynamic axial and bending moment loads which generated internal contact pressures.” The AAIB’s extensive two-volume report goes on to note that the original analysis of the bearing’s theoretical load spectrum was not validated by flight test results to assess the bearing’s suitability for this application, which was not required by regulation; and that “no design or test requirements in Certification Standard 29…explicitly addressed rolling contact fatigue in bearings identified as critical parts.” It described certification testing of the bearing as “not sufficiently representative of operational demands to identify the failure mode” and asserted that “the various failure sequences and possible risk reduction and mitigation measures within the wider tail rotor system were not fully considered in the certification process.” Finally, the helicopter manufacturer did not require routine inspection of critical part bearings.
“Nascar Race” Approach Ends in Overrun, Israel Aircraft Industries/Gulfstream G150, May 5, 2021, Ridgeland, South Carolina
The pilots’ decision to “race” another inbound jet led them to fly an unstable approach, both high and fast, and make a straight-in approach with a quartering tailwind that exceeded the manufacturer’s operational limit.
The nose and right main landing gear were partially sheared and the wings and fuselage substantially damaged after the jet rolled off the end of the runway, coming to rest in marshy terrain about 400 feet past the departure threshold. There were no injuries to either pilot or any of the three passengers.
The NTSB report quotes extensively from the cockpit voice recorder (CVR). While en route from New Smyrna Beach, Florida, the pilots concluded that reports from nearby airports of winds from 240 to 250 degrees favored landing straight in on Runway 36. After a passenger inquired about their arrival time, the PIC promised, “I’ll speed up. I’ll go real fast here.” He estimated their arrival time at 10:35 and that of another jet inbound to Ridgeland as 10:33, then told the SIC, “They’ll slow to 250 [knots] below 10 [thousand feet] and we won’t. We know what we’re doing right now, we’re trying to win a race…This is Nascar.”
The overspeed warning sounded multiple times during descent, once for eight seconds. The PIC said, “Goal achieved” and the SIC replied, “Final lap.” Two minutes after the crew requested a straight-in approach to Runway 36, the controller advised the other jet that they were number two for the airport. The autopilot was disconnected with the Gulfstream 1.5 miles from the runway and descending through 900 feet at 170 knots, nearly 50 knots above their reference landing speed of 121.
Multiple sink-rate warnings sounded as it slowed to 150 and then 130 knots. It touched down about 1,000 feet down the 4,200-foot runway at an estimated 120-128 knots and immediately deployed thrust reversers, but the ground air brakes failed to deploy for undetermined reasons.
Tire marks on the runway only showed evidence of heavy braking in the last 1,000 feet of the runway. The airport has no weather reporting, but a pilot-rated witness estimated the winds as coming from 220 to 230 degrees at 11 to 13 knots; footage captured by another witness showed the 15-knot windsock fully extended. The Gulfstream’s flight manual cites a maximum allowable tailwind component of 10 knots.
Improper Loading Implicated in Approach Stall, Piper PA-46-360P JetProp DLX Conversion, Dec. 14, 2022, Goose Bay, Newfoundland and Labrador, Canada
Canada’s Transportation Safety Board (TSB) determined that the single-engine turboprop was above its rated maximum gross weight with its center of gravity well forward of limits not only on departure from Quebec’s Sept-Îles Airport, but also throughout its approach to Goose Bay. The pilot and only passenger suffered serious injuries when the airplane stalled onto the final approach course about 2.5 nm short of the airport during an RNAV approach to Runway 08. Both were evacuated by a Canadian Forces rescue helicopter based at Goose Bay, but the pilot subsequently died of his injuries.
The airplane crossed the initial approach fix at 2,800 feet and 104 knots groundspeed, then began tracking a three-degree descent path while slowing to 70 knots seven miles from the airport. It accelerated to 80 knots after the tower advised a following aircraft that they were number two for the runway, then slowed again after the pilot received his landing clearance.
The final ADS-B data point showed a groundspeed of 51 knots just before the airplane departed controlled flight on the runway’s extended centerline. The rescue helicopter reached the site three minutes after the 406 MHz ELT signal was detected.
The U.S.-registered aircraft was based in Switzerland, but had returned to the U.S. for extensive avionics upgrades. It departed Sept-Îles with a full load of 151 gallons (1,057 pounds) of jet-A, and TSB investigators determined that it was 475 pounds over its certified maximum takeoff weight, with its center of gravity 1.9 inches ahead of its forward limit. At the time of the accident, it was calculated to still be 48 pounds overweight with its center of gravity 2.1 inches forward of limits.
The TSB’s report notes that both the excess weight and the forward c.g. would have served to increase the airplane’s stall speed, which is normally 69 knots clean and 58 in the landing configuration. The JetProp flight manual calls for a final approach speed of 90 knots with flaps extended or 100 knots without, while two independent training providers contacted by investigators recommended maintaining at least 120 knots on final approach. ζ