Pilot Debrief

CESSNA 172K near Neenah, WI — 2016-08-02

Final reportCEN16LA309
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Date
2016-08-02
Location
Neenah, WI, USA
Aircraft
CESSNA 172K
Registration
N46459
Category
Airplane
Highest injury
None
Fatalities
0
Phase of flight
Cruise

Probable cause

A loss of engine power due to oil starvation, which resulted from the pilot, who was not a certified airframe and powerplant mechanic, removing the vacuum pump from the engine, and his misconception that he could operate the airplane without the pump.

NTSB narrative

The private pilot was conducting the first flight in the airplane after having removed a failed vacuum pump from the engine; the pilot was not a certified airframe and powerplant mechanic. During the flight, the engine lost power, and the pilot subsequently landed the airplane on a highway, and the left wing contacted a road sign, which resulted in substantial damage. The pilot reported that he had recently had a mechanic remove a failed vacuum pump on a different airplane that he owned and that he was able to fly that airplane without the pump. As a result, he thought he could also fly the accident airplane without a vacuum pump. However, the vacuum pumps were mounted on each airplane differently, and the pilot's removal of the vacuum pump on the accident airplane allowed oil to exit the engine through the drive gear opening on the accessory case, which resulted in oil starvation.

Analysis

Primary failure mode
Engine power loss
First missed decision gate
Pilot should have installed a cover plate over the vacuum pump mounting pad.

NTSB coding

Evidence available

  • 1 docket document
View NTSB final reportView NTSB docket

Docket documents1

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