Cessna T210N N6191N

Summary

On 20 January 1994 at about 01:30 local time, a Cessna T210N registered N6191N was involved in an accident near Hayesville, North Carolina, United States. 2 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 January 1994 at 01:30

Classification

Accident

Location

Hayesville, North Carolina, United States

Coordinates

35.0395, -83.8110

Aircraft

Cessna T210N

Registration

N6191N

Category

Airplane

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Business

Phase of flight

Not recorded

Route

Asheville → Fort Payne

Aircraft damage

Substantial

Weather

VMC

Light

Night/Dark

NTSB number

ATL94LA041

Nobody was injured.

THE FATIGUE FAILURE OF NO. 2 EXHAUST VALVE WHICH RESULTED FROM EXCESSIVE HEAT AND WEAR TO THE VALVE STEM. A FACTOR WAS THE DARK NIGHT.

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

Read the full NTSB narrative

ABOUT 30 MINUTES INTO THE FLIGHT, THE PILOT REPORTED A COMPLETE LOSS OF ENGINE POWER. WHILE MANEUVERING FOR AN EMERGENCY LANDING TO A PUBLIC ROAD, THE PILOT SPOTTED AN OPEN FIELD AND COMPLETED A FORCED LANDING. EXAMINATION OF THE ENGINE ASSEMBLY DISCLOSED THAT NUMBER TWO EXHAUST VALVE FAILED IN FATIGUE AT THE RADIUS BETWEEN THE VALVE STEM AND THE VALVE HEAD. THE METALLURGICAL EXAMINATION REVEALED A DECREASE IN THE HARDNESS OF THE HEAD END OF THE VALVE, LOSS OF THE CHROMIUM PLATING OVER MUCH OF THE LENGTH OF THE VALVE STEM AND EXCESSIVE WEAR OF THE CENTER PORTION OF THE VALVE STEM. THE VALVE STEM WAS DARKLY COLORED, NORMALLY ASSOCIATED WITH HIGH TEMPERATURES, OVER ONE HALF THE LENGTH OF THE VALVE STEM. THE PART NUMBER STAMPED ON THE EXHAUST VALUE CORRESPONDED TO AN AFTER-MARKET SUPPLIER'S NUMBER.

Quoted verbatim from the NTSB record.