Cirrus SR22 N8135B

Summary

On 28 January 2011 at about 00:19 local time, a Cirrus SR22 registered N8135B, operated by Deep South Express LLC, was involved in an accident near Cross City, Florida, United States. One person was on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

28 January 2011 at 00:19

Classification

Accident

Location

Cross City, Florida, United States

Coordinates

29.7908, -82.9869

Aircraft

Cirrus SR22

Registration

N8135B

Category

Airplane

Engines

1

Operator

Deep South Express LLC

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Eufaula → Leesburg

Aircraft damage

Substantial

Weather

VMC

Light

Night

NTSB number

ERA11LA130

Nobody was injured.

A total loss of engine power resulting from the failure of the camshaft due to fatigue cracks. Contributing to the accident was the inadequate quality inspection of the camshaft after initial manufacture.

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

Read the full NTSB narrative

The airplane’s engine lost power during cruise flight at 9,000 feet, and the pilot declared an emergency. Air traffic control (ATC) personnel initially provided the pilot with headings to a nearby airport. However, when the pilot realized that he would not reach the intended airport, he deployed the airplane’s parachute, and the airplane came to rest upright in a field. Postaccident examination of the engine revealed that the camshaft was completely fractured due to fatigue cracks near the flange at the oiling holes. Further examination showed that the fatigue cracks initiated at the edge of the oiling holes and were caused by burrs left when the camshaft was originally manufactured. The burrs folded over during subsequent shot-peening operations, which formed laps at the corners of the holes; the laps acted to concentrate stresses at the edges of the holes and also shielded the underlying material during shot peening. The laps prevented formation of the beneficial compressive stresses that result from shot peening. This allowed subsequent formation of fatigue cracks. The accident camshaft was determined to have been the 19th camshaft of its type manufactured. Because the camshaft was not a serialized part, specific manufacturing records could not be located. However, the quality control inspection procedures that were in place at the time the camshaft was manufactured required an inspection of the oil holes for proper de-burring. A search of FAA database revealed no similar camshaft fracture failure between 1995, and February 2012, excluding the accident event.

Quoted verbatim from the NTSB record.