Bearhawk LSA N1908A

Summary

On 30 April 2022 at about 14:04 local time, a Bearhawk LSA registered N1908A was involved in an accident near Kalispell, Montana, United States. 2 people were on board and 2 died. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

30 April 2022 at 14:04

Classification

Accident

Location

Kalispell, Montana, United States

Coordinates

48.2859, -114.4033

Aircraft

Bearhawk LSA

Registration

N1908A

Category

Airplane

Year built

2018

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Kalispell → Eureka

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR22FA169

2 people died.

An excessive pitch control input for undetermined reasons while the airplane was operating above maneuvering speed, which led to a structural failure of the right wing during cruise flight. Contributing to the accident was the poor construction quality of the airplane and the inadvertent omission by the pilot/builder of a series of structural airframe components.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

The experimental amateur-built airplane was flying in trail behind a group of two other airplanes. The takeoff appeared to be uneventful and the weather unremarkable. Automatic dependent surveillance-broadcast (ADS-B) data indicated that, after climbing to about 1,850 ft above ground level (agl), the airplane leveled off and accelerated to cruise speed. About 1 minute later, the airplane appeared to aggressively pitch down, then up, then down again before the right wing separated from the airplane and the airplane descended to impact the terrain. Damage signatures indicated that the right wing initially folded downwards almost 90° before breaking away in an upwards direction, likely as the airplane rolled to the right. The pilot built the airplane from plans, and its primary fuselage structure was made of tubular steel covered in fabric. He used an unapproved welding process to construct the airframe and used thicker walled tubing to compensate. Postaccident examination of the wreckage showed the weld quality was generally poor, and a set of structural bracing components in the main wing spar carry-through section was omitted. Even with the poor build quality, the steel airframe structure appeared to be intact before impact. The omission of the braces alone would not have resulted in the failure of the wing as observed: however, the combined effect of the omission and modifications would have affected the overall structural integrity of the airplane. ADS-B data showed the airplane was traveling below the never exceed speed (Vne), but well over maneuvering speed (Va) at the time of the breakup; therefore, an aggressive control input would likely have resulted in structural damage. A negative failure of the right wing, as observed, could have been caused by a nose-down control input, and the ADS-B data indicated that the airplane had aggressively pitched down just before the breakup. The resolution of the ADS-B data did not allow for an accurate assessment of the g-forces encountered during the final oscillations. The airplane was equipped with dual controls including a center stick. The passenger, who was seated in the rear of the airplane had not flown with the pilot in the airplane before. The passenger’s seatbelt was not buckled when examined, and although it had sustained damage it still appeared to operate. The damage observed did not explain why it was unbuckled. If the passenger was unrestrained, inadvertent flight control operation could not be ruled out. Additionally, although friends stated that it was not in the pilot’s nature to take risks, his performance of an ostentatious maneuver just before the breakup could not be ruled out.

Quoted verbatim from the NTSB record.