Soar Loser

The NTSB has released its preliminary report on a 05 July 2023 accident in which an  Avia Stroitel AC-5M motor-glider, registration N40233, sustained substantial damage and its Private Pilot certificated single occupant was seriously injured after departing Skyport Airport (4S4), a public use airport some three-nautical-miles north of the central business-district of Cornelius, Oregon—a city 19.7-nautical-miles west-southwest of Portland International Airport (PDX).

Skyport Airport is privately owned and features a single, two-thousand-foot-long, 45-foot-wide, turf-and-gravel-surfaced runway. The facility averages approximately two-thousand general aviation aircraft operations annually.

The accident aircraft was operated as a personal flight under Part 91 of the Federal Aviation Regulations.

Witnesses reported the Avia Stroitel AC-5M’s pilot had purchased the motor-glider some two-months prior to the accident and had trailered the aircraft continuously since acquiring such.

The motor-glider was assembled on the morning of the accident—the assembly process having been documented via still-photographs and video by a local soaring club. The pilot’s determination of the AC-5M’s airworthiness was similarly chronicled.

The motor-glider was towed to an altitude of 3,200-feet-MSL and released without incident from the tow-aircraft. The AC-5M’s pilot set forth he subsequently extended and retracted the glider’s motor before hearing what he called a “bang.”

An uncommanded spin ensued.

The pilot, who was wearing a parachute, ejected from the glider at an altitude of approximately two-thousand-feet MSL. The aircraft impacted the ground, coming to rest on its side. Both of the AC-5M’s wings were discovered approximately two-hundred-feet from the main wreckage—which comprised the glider’s fuselage, empennage, and motor.

Examination of the wreckage by a Federal Aviation Administration inspector revealed the glider’s wing-mounting attachment pin remained in the wing-mounting box. However, the right wing attachment tab was separated at the wing-root. The wreckage, in accordance with Federal Aviation Regulation, was recovered to a secure facility for further examination.  

FMI: www.ntsb.gov