Cessna 172R N2478B

Summary

On 8 March 2009 at about 01:50 local time, a Cessna 172R registered N2478B, operated by Alan Jacobson, was involved in an accident near Oceanside, California, United States. 3 people were on board and 2 were seriously injured, one 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

8 March 2009 at 01:50

Classification

Accident

Location

Oceanside, California, United States

Coordinates

33.2992, -117.4675

Aircraft

Cessna 172R

Registration

N2478B

Category

Airplane

Engines

1

Operator

Alan Jacobson

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Santa Ana → San Diego

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR09LA145

2 people were seriously injured.

A total loss of engine power in flight due to the fatigue failure of the No. 4 cylinder.

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

Read the full NTSB narrative

The pilot made an off-airport forced landing following an in-flight loss of engine power. The No. 4 cylinder (left rear) fractured and separated circumferentially in the area where the head joins the barrel. Metallurgical examination identified a fatigue fracture primarily on the exhaust side of the cylinder head, perpendicular to the axis of the barrel. Its inner edge abutted the crest of the first thread on the barrel. Engine Components, Inc. (ECi), manufactured the cylinder. ECi issued Mandatory Service Bulletin (MSB) No.08-1, Revision 3, dated August 19, 2008. It stated that the purpose of the MSB was to alert their customers about possible fatigue cracking and head separations on a specified group of replacement cylinders for Lycoming parallel valve engines. Cylinders identified by specific serial number ranges were to be inspected and pressure tested or inspected and replaced at specified reduced life limits. On October 20, 2008, Federal Aviation Administration (FAA) Airworthiness Directive (AD) 2008-19-05 became effective and mirrored ECi's MSB serial number range and corrective actions. The AD stated that the intent was to prevent loss of engine power due to cracks at the head-to-barrel interface in the cylinder assemblies and possible engine failure caused by separation of a cylinder head. The cylinders from the accident airplane had serial numbers that were outside of the range listed in the MSB and AD. The FAA has issued a Notice of Proposed Rule Making (NPRM) that would revise the serial numbers covered by the AD to encompass an expanded population of affected cylinders. ECi has a design change that is pending FAA approval.

Quoted verbatim from the NTSB record.