Stanley GLASAIR SH-2 N309TS

Summary

On 21 March 2004 at about 20:43 local time, a Stanley GLASAIR SH-2 registered N309TS was involved in an accident near San Luis Obispo, California, United States. One person was on board and 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

21 March 2004 at 20:43

Classification

Accident

Location

San Luis Obispo, California, United States

Nearest airport

San Luis County Regional Airpo (SBP)

Coordinates

35.2333, -120.6333

Aircraft

Stanley GLASAIR SH-2

Registration

N309TS

Category

Airplane

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Corcoran → San Luis Obispo

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

LAX04LA169

1 person had minor injuries.

The loss of engine power due to the failure of the #3 cylinder piston and connecting rod for undetermined reasons.

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

Read the full NTSB narrative

The airplane experienced a loss of engine power and impacted a ditch during the pilot's forced landing in a field. While approaching the proximity of the destination airport, the pilot observed the engine gauges indicating rising oil temperature. About 5 miles from the airport, the engine emitted a loud noise and he declared an emergency due to an engine failure. Realizing that he would be unable to make it to the runway, the pilot executed a forced landing in a field; during the landing roll, the airplane impacted a ditch and tumbled. Post-accident external visual examination by a Federal Aviation Administration (FAA) inspector revealed that the engine sustained a catastrophic failure, with a hole knocked in the upper case spine above the rear cylinders. Looking through the hole, the inspector observed that the right rear piston had seized in the No. 3 cylinder and its respective connecting rod was broken just above crankshaft rod end flare. The inspector could not identify the rod end cap or the bearing shells. The No. 3 piston skirt was visibly scorched in the direction of piston travel. A visual examination of the engine, disclosed that all of the cylinders were worn and scored. After the accident, the owner took the engine to a maintenance facility that examined the engine and reported that rod bearing in the No. 3 cylinder failed. The facility declined to provide detailed observations on the internal condition of the engine, the rod fracture, and condition of the bearing. The FAA inspector said the pilot told him that prior to the accident, the engine was experiencing excessive oil consumption. In response, the pilot removed the No. 3 cylinder from the engine and employed an engine shop to change the piston in an effort to alleviate the excessive oil consumption problems. After the maintenance was preformed, the pilot reinstalled the cylinder. The inspector added that sometime prior to the accident the pilot had also modified the engine by installing larger pistons.

Quoted verbatim from the NTSB record.