Pilot Debrief

GRUMMAN G164 - B near Princeton, CA — 2015-08-04

Final reportWPR15LA230
Sign in to save
Date
2015-08-04
Location
Princeton, CA, USA
Aircraft
GRUMMAN G164 - B
Registration
N48452
Category
Airplane
Highest injury
None
Fatalities
0
Phase of flight
Maneuvering

Probable cause

The loss of engine power during an agricultural application flight due to a cylinder failure.

NTSB narrative

The pilot reported that, during the agricultural spray run, the engine lost power. The airplane was unable to maintain altitude, so the pilot made a forced landing to a rice field. After touchdown, the airplane nosed over, which resulted in substantial damage to the rudder. A postaccident examination of the engine revealed that the No. 2 cylinder head had cracked and lifted under the cooling fins on the cylinder's left side. The crack continued across the top and inside of the head to the intake valve seat, which would have allowed hot gases to enter the induction system and resulted in the subsequent loss of power. A review of the airplane's maintenance records revealed that a mandatory 100-hour repetitive visual inspection of the cylinder had been performed 66.7 flight hours before the accident flight.

Analysis

Primary failure mode
Engine power loss
First missed decision gate
Performing more frequent inspections could have prevented the cylinder head failure.

NTSB coding

Evidence available

  • 6 docket documents
View NTSB final reportView NTSB docket

Docket documents6

Related mishaps