Pilot Debrief

NORTHLAND AVIATION LLC IVP near Lovelock, NV — 2016-10-20

Final reportWPR17LA012
Sign in to save
Date
2016-10-20
Location
Lovelock, NV, USA
Aircraft
NORTHLAND AVIATION LLC IVP
Registration
N4YB
Category
Airplane
Highest injury
Minor
Fatalities
0
Phase of flight
Initial climb

Probable cause

A total loss of engine power due to the failure of the intake valve in the No. 3 cylinder for reasons that could not be determined based on the available information.

NTSB narrative

The airline transport pilot reported that, while climbing to cruise altitude, about 9 minutes into the cross-country flight, he felt a severe shudder and the engine experienced a total loss of power. Simultaneously, oil began to coat the windscreen. The pilot maneuvered for a nearby airport; however, as he neared the airport, he realized that the airplane would not reach the runway and elected to land in an open area of desert vegetation. Postaccident examination of the engine revealed a hole in the crankcase above the Nos. 3 and 4 connecting rod journals. The Nos. 3 and 4 pistons were fractured into several pieces, which were located within the engine. The No. 3 connecting rod had separated from the crankshaft. The No. 3 cylinder intake valve head was broken at the bottom of the valve guide; the valve head was not located within the engine. A visual examination by a metallurgist was unable to determine the initial failure mode given the postfracture mechanical damage to the fractured end of the valve stem and the absence of the separated valve head; however, due to the quantity and severity of damage found throughout the engine, the likely initial point of failure was a fracture to the intake valve in the No. 3 cylinder.

Analysis

Primary failure mode
Engine power loss
First missed decision gate
Pilot could have aborted the flight after the severe shudder.

NTSB coding

Evidence available

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

Docket documents8

Related mishaps