Amateur-built LB-1 N555LB accident near Haines, Alaska

Probable cause

A partial loss of engine power for reasons that could not be determined based on available information, which resulted in a precautionary landing and impact with snow.

NTSB analysis

After performing a preflight inspection and a successful run-up of the engine, the pilot initiated a takeoff. After becoming airborne, the engine “faltered.” The pilot lowered the nose, decreased the flaps, and confirmed that the throttle was set at the full power position, but the airplane continued to descend. During a precautionary landing, the airplane bounced; on the second touchdown the tires sunk into the snow and the airplane nosed over, coming to rest inverted.

The pilot reported that he did not believe there was any type of internal engine failure. A postaccident engine run revealed no evidence of any preaccident mechanical malfunctions or failures that would have precluded normal operation. A review of the weather conditions found that they were not conducive to carburetor ice. A reason for the partial loss of engine power could not be determined based on the available information.

Text from the NTSB. Open the NTSB docket for ANC22LA011 for the full record.