Pilot Debrief

BEECH 35-B33 near Baker, NV — 2021-09-11

Final reportWPR21LA358
Sign in to save
Date
2021-09-11
Location
Baker, NV, USA
Aircraft
BEECH 35-B33
Registration
N8983M
Category
Airplane
Highest injury
None
Fatalities
0
Phase of flight
Initial climb

Probable cause

A total loss of engine power during the initial climb due to the failure of the No. 5 connecting rod bearing.

NTSB narrative

The accident flight occurred after a mechanic replaced the exhaust pushrod for the No. 1 cylinder. After takeoff and during the initial climb, the engine lost total power. The airplane sustained substantial damage during a forced landing in desert terrain. Postaccident examination of the engine revealed that the No. 5 connecting rod strap exhibited fracture signatures consistent with fatigue cracks in multiple areas. The connecting rod also exhibited signs of heat distress. The No. 5 connecting rod bearing was severely worn, deformed, flattened, and darkened, consistent with high heat exposure. The general heat tinting and damage on the bearing, connecting rod, and crankshaft journal indicated that the No. 5 connecting rod bearing likely experienced frictional heating from insufficient clearance between the bearing and the journal. The insufficient clearance could have been produced by excessive wear on the bearing or journal, bearing surface damage such as spalling, or insufficient lubrication.

Analysis

Primary failure mode
Mechanical failure
First missed decision gate
Pilot could have opted for a thorough preflight inspection after mechanic's work.

NTSB coding

Evidence available

  • Photos
  • 6 docket documents
View NTSB final reportView NTSB docket

Docket documents6

Related mishaps