Beech A100 N93GT accident near West Helena, Arkansas

Probable cause

The malfunction of the propeller autofeather system after takeoff for undetermined reasons, which resulted in both propellers going into feather and a hard landing.

NTSB analysis

The pilot reported that immediately after takeoff, both propeller assemblies went into a feathered condition. The pilot was able to maneuver the airplane back to a runway. After a hard landing, the left tire blew, the airplane exited the runway, and the airplane’s left wing sustained substantial damage.

On the day before the accident flight, the airplane underwent maintenance to troubleshoot a propeller autofeather issue. A mechanic tested the autofeather system and replaced a low-pressure switch. After the maintenance, the mechanic conducted operational checks and performed ground runs; no defects were found. The airplane was returned to service, and the pilot flew the airplane the next day, before the accident flight, without any reported mechanical issues.

Postaccident examinations of the cockpit control pedestal and feathering systems did not reveal any anomalies. All propeller condition lever controls were intact and had a full range of motion. Both left and right engine throttle controls were intact and had a full range of motion. Inspections of all accessible wiring and components within the engine nacelles, as well as those contained within the cabin of the aircraft and rigging under the floor panels, revealed no anomalies. Examination of both engines’ propeller governors, fuel control units (FCUs) and beta valves did not reveal any anomalies. These detailed examinations could not determine the reason for the reported propeller feather issue on takeoff.

Text from the NTSB. Open the NTSB docket for CEN22LA085 for the full record.