Cessna T210L N5378V

Summary

On 20 August 1999 at about 02:05 local time, a Cessna T210L registered N5378V was involved in an accident near Byron, California, United States. 6 people were 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

20 August 1999 at 02:05

Classification

Accident

Location

Byron, California, United States

Coordinates

37.8494, -121.6208

Aircraft

Cessna T210L

Registration

N5378V

Category

Airplane

Engines

1

Operator

Not recorded

Operating rule

Part 135: Air Taxi & Commuter

Purpose of flight

Unknown

Phase of flight

Not recorded

Route

Groveland → Concord

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

LAX99LA277

Nobody was injured.

The failure of the operator's maintenance personnel to properly torque the cylinder and engine case through bolts during the replacement of five cylinders, which led to the spinning of the No. 2 main bearing and the resultant oil starvation induced catastrophic internal engine failure.

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

Read the full NTSB narrative

The pilot said the aircraft was in level cruise at 6,500 feet msl when the engine suddenly quit without warning. The pilot switched fuel tanks and turned on the electric boost pump, which restored fuel flow on the gage, but the engine did not restart. Coincident with the loss of power, the pilot heard a 'pop' sound come from the engine compartment. The pilot selected an open field and continued to attempt a restart as he prepared for the off-airport landing. The aircraft touched down in the field and rolled some distance before the nose gear collapsed. During the teardown inspection of the engine, all cylinder bases and through bolt studs exhibited evidence of oil leakage. During removal of the cylinders, all through bolt and cylinder hold down stud nuts were loose enough to break torque with one hand using a short open-end wrench. Removal of the cylinders revealed fretted cylinder bases and pads. Separation of the case halves revealed fretting on all cylinder pads and bearing saddle-parting surfaces, with more fretting observed on the No. 2 main bearing saddle surfaces. The No. 2 main bearing was fragmented and found in the oil sump, with erosion and smearing evident to the bearing saddle. The crankshaft was fractured across the No. 3 short cheek, with heavy scoring evident to the Nos. 2 and 3 main journals. Review of the maintenance records disclosed that cylinders 1, 2, 4, 5, and 6 were replaced on March 24, 1997, 232 hours prior to the accident.

Quoted verbatim from the NTSB record.