Cessna U206 N5229U

Summary

On 25 November 2012 at about 23:05 local time, a Cessna U206 registered N5229U, operated by Clipper 29 Uniform LLC, was involved in an accident near Van Nuys, California, United States. 2 people were on board and 2 had minor injuries. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

25 November 2012 at 23:05

Classification

Accident

Location

Van Nuys, California, United States

Nearest airport

Van Nuys (VNY)

Coordinates

34.2428, -118.5236

Aircraft

Cessna U206

Registration

N5229U

Category

Airplane

Year built

1964

Engines

1

Operator

Clipper 29 Uniform LLC

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Novato → Santa Ana

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR13LA052

2 people had minor injuries.

A partial loss of engine power during cruise flight due to fatigue fractures of two crankshaft gear teeth from corrosion pitting, which resulted in an off-airport forced landing and collision with obstacles on the ground.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

The pilot reported that the airplane was in cruise flight when the engine started backfiring and he smelled burnt oil; the engine subsequently lost partial power. During the forced landing on a soccer field, the airplane sustained substantial damage when it collided with a fence and trees before coming to rest on its left side. Postaccident examination of the engine revealed that the engine crankshaft would not rotate. A borescope inspection revealed that a valve in the No. 2 cylinder was in contact with a piston face. All of the piston heads exhibited semicircular indentations near the location of the valves. Upon disassembly, six gear teeth on the crankshaft gear were found fractured, and all of the teeth on the camshaft gear were found ground off. A metallurgical examination of the separated crankshaft gear teeth revealed that two of the fracture surfaces exhibited fatigue with areas of corrosion pitting and that the other fracture surfaces exhibited evidence of overload.

Quoted verbatim from the NTSB record.