Piper PA-28R-201T N40437

Summary

On 31 December 1996 at about 20:50 local time, a Piper PA-28R-201T registered N40437, operated by Sandra S. McKenna, was involved in an accident near Raton, New Mexico, United States. 4 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

31 December 1996 at 20:50

Classification

Accident

Location

Raton, New Mexico, United States

Coordinates

36.8807, -104.4391

Aircraft

Piper PA-28R-201T

Registration

N40437

Category

Airplane

Engines

1

Operator

Sandra S. McKenna

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Midland → Trinidad

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

FTW97LA077

Nobody was injured.

failure of the exhaust rocker arm retaining studs due to over torquing of the attachment bolts by maintenance personnel during installation. A factor 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

The pilot reported that while in cruise flight the airplane shuddered and began to lose power. She changed the fuel selector from the right to left tank; checked the fuel mixture, the exhaust gas temperature, and the instrument panel. The pilot reported that the engine performance continued to decay and she initiated a forced landing to a pasture. Examination of the engine revealed that the number two cylinder exhaust rocker arm retaining studs had separated. Examination of the studs by a metallurgist revealed that over torquing of the attachment nuts during installation caused plastic deformation of the studs and probable cracking in the threads which led to a fatigue crack in at least one of the studs. The fatigue crack led to the subsequent failure of the exhaust rocker arm retaining studs.

Quoted verbatim from the NTSB record.