Pilot Debrief

BEECH H35 near Green Lake, WI — 2010-07-25

Final reportCEN10LA433
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Date
2010-07-25
Location
Green Lake, WI, USA
Aircraft
BEECH H35
Registration
N5443D
Category
Airplane
Highest injury
None
Fatalities
0
Phase of flight
Descent

Probable cause

A total loss of engine power during descent due to the overhaul facility’s inadequate maintenance.

NTSB narrative

The pilot reported that, while on approach to the destination airport, the engine experienced a total loss of power. He selected an uphill-sloped soybean field to make a forced landing and retracted the landing gear. The airplane slid 260 feet before coming to a stop. The airplane sustained firewall damage during the landing sequence. The postaccident investigation revealed several anomalies with the engine that were not in accordance with engine manufacturer's recommended maintenance practices. The No. 2 bearing was dislodged/separated and remnants of it were most likely the metallic debris found in the oil sump and oil filter. The cylinder thru-bolts were found to be tight; however, 19 of the 36 cylinder deck stud nuts were loose. A crack was observed between the No. 4 main bearing saddle on the left half of the crankcase, which extended through the No. 5 main bearing saddle. The pilot reported that the airplane had undergone a top overhaul about 18 flight hours prior to the accident. At the conclusion of the examination, the exact cause of the engine failure could not be definitively identified.

Analysis

Primary failure mode
Engine power loss
First missed decision gate
Pilot could have conducted a go-around or diverted earlier to avoid engine failure.

NTSB coding

Evidence available

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

Docket documents9

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