Polstra ZODIAC CH 601 HDS N721PT

Summary

On 16 June 2003 at about 13:27 local time, a Polstra ZODIAC CH 601 HDS registered N721PT was involved in an accident near Thomson, Georgia, United States. One person was 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

16 June 2003 at 13:27

Classification

Accident

Location

Thomson, Georgia, United States

Nearest airport

Thomson McDuffie County (KHQU)

Coordinates

33.5297, -82.5167

Aircraft

Polstra ZODIAC CH 601 HDS

Registration

N721PT

Category

Airplane

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Marietta → Thomson

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

ATL03LA106

Nobody was injured.

The total loss of engine power due to the fatigue fracture of the No. 3 cylinder intake valve, which resulted in a forced landing to rough terrain and subsequent collision with small trees and a tree stump.

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

Read the full NTSB narrative

During cruise flight, the engine began to run rough and lose power, then it stopped completely. The pilot executed an emergency landing in a field, and the airplane collided with small trees and a tree stump. Examination of the engine revealed the intake valve on the No. 3 cylinder was fractured in the transition region between the stem and the head with no bending deformation. Metallurgical examination revealed the lock for the spring seat displayed fretting damage at the internal and external faces. Fretting damage was observed on the corresponding surface of the stem portion of the valve and on the corresponding bore face of the spring seat. The fretting damage was characteristic of higher than normal operating stresses or vibration and fatigue.

Quoted verbatim from the NTSB record.