Pilot Debrief

BEECH V35 near Walters, OK — 2017-07-08

Final reportCEN17LA286
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Date
2017-07-08
Location
Walters, OK, USA
Airport
OK12
Aircraft
BEECH V35
Registration
N6257V
Category
Airplane
Highest injury
Minor
Fatalities
0
Phase of flight
Climb

Probable cause

Maintenance personnel’s installation of an improper vacuum pump gasket, which resulted in oil starvation to the engine and a subsequent total loss of engine power.

NTSB narrative

The airline transport pilot was conducting a personal, cross-country flight. He reported that, about 10 minutes after takeoff, the oil pressure decreased to 0, and the engine experienced a loss of all power. The pilot conducted a forced landing on a soft field about 1 mile short of an airport, during which the airplane sustained substantial damage to the firewall and lower fuselage. A review of the airplane's maintenance records revealed that the vacuum pump had been replaced the day before the accident. Examination of the engine revealed that three connecting rods exhibited thermal and impact damage, and three rod journals were found dry and exhibited thermal discoloration, indicative of oil starvation. Disassembly indicated that a gasket typically used for carburetors was installed on the vacuum pump. The installed gasket did not completely cover the high-pressure oil orifice on the vacuum pump mounting fixture, which resulted in oil leakage, subsequent oil starvation to the engine, and the loss of engine power.

Analysis

Primary failure mode
Mechanical failure
First missed decision gate
Proper gasket installation could have prevented engine failure.

NTSB coding

Evidence available

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

Docket documents7

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