Cessna P210N N4839P

Summary

On 29 March 2008 at about 22:54 local time, a Cessna P210N registered N4839P, operated by Roger L. Millheim, was involved in an accident near Elizabeth, Colorado, United States. 3 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

29 March 2008 at 22:54

Classification

Accident

Location

Elizabeth, Colorado, United States

Coordinates

39.6000, -104.1000

Aircraft

Cessna P210N

Registration

N4839P

Category

Airplane

Engines

1

Operator

Roger L. Millheim

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Lamar → Denver

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

DEN08LA069

Nobody was injured.

the loss of engine power due to the fatigue failure of the camshaft gear. Contributing to the accident was the lack of suitable terrain for the forced landing.

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

Read the full NTSB narrative

During a normal descent on approach for landing at 8,500 feet mean sea level, the engine "let go/popped into a higher pitch sound, and the power dropped off. [The pilot] checked the fuel flow, tried to get power with the throttle, but no response." During a forced landing, the airplane impacted the side of a gravel road, traveled across the road, struck a ditch, and skidded on the fuselage bottom for approximately 75 feet were it came to rest upright in a residential yard. Examination of the engine exhibited fretting on all six cylinder decks and the main bearing case half sections. The number 2 main bearing support bearing tang lock-slot was found elongated. Various degrees of wear were noted on all crankshaft main bearings, and the number 2 main bearing showed additional wear. The crankshaft number 2 main journal exhibited signatures of thermal discoloration. All oil transfer galleries were free and clear of debris. The camshaft was intact, however, the camshaft gear had a semi-circular section with 7 gear teeth separated, which was found in the gearbox. Metallurgical examination showed the fracture initiated at the surface and progressed in fatigue. The initiation site was damaged; however, the approximate location was identified by crack arrest lines, which encircled the origin. The reason for the fracture initiation could not be determined.

Quoted verbatim from the NTSB record.