Pilot Debrief

CESSNA U206G near West Sacramento, CA — 2024-09-19

Final reportWPR24LA314
Sign in to save
Date
2024-09-19
Location
West Sacramento, CA, USA
Airport
KSAC
Aircraft
CESSNA U206G
Registration
N6522Z
Category
Airplane
Highest injury
Minor
Fatalities
0

Probable cause

Failure of the No. 4 cylinder fuel injection assembly tube and subsequent total loss of engine power.

NTSB narrative

While the airplane was en route to a local airport, the engine suddenly lost power and the airplane began to shake. The pilot noted rapidly decreasing cylinder head temperature readings on most cylinders and the loss of the temperature reading for the No. 4 cylinder. He turned the airplane toward the nearest airport, and the engine then lost all power. The pilot realized that the airplane would not glide to the nearest airport and selected a field to land in. He initiated an emergency landing to the field and the airplane nosed over, coming to rest inverted. Postaccident examination of the engine revealed that the No. 4 fuel injection assembly tube was not contained in its retention clamp, and the elastomer sleeve that cushions the clamped tube was displaced from its normal position. Examination of the tube during disassembly revealed a fracture where it intersected the shank of the ferrule that had been brazed onto the inboard end of the tube. Further examination of the fracture at the NTSB laboratory revealed that the fracture surfaces were consistent with fatigue and that the elastomer sleeve displayed wear marks consistent with previous clamping. The engine’s fuel flow divider was tested with the five intact fuel injection assembly tubes from the accident engine and one surrogate tube for the No. 4 position. The flow test failed when the No. 4 tube was removed to simulate the fracture. The investigation could not determine how long the No. 4 fuel injection assembly tube had been displaced from the retention clamp before the tube’s in-flight failure and subsequent engine failure.

NTSB coding

Evidence available

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

Docket documents8

Related mishaps