Piper PA-28-140 N9898W

Summary

On 2 July 2014 at about 13:42 local time, a Piper PA-28-140 registered N9898W, operated by Iron Compass Aviation, was involved in an accident near Granbury, Texas, 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

2 July 2014 at 13:42

Classification

Accident

Location

Granbury, Texas, United States

Nearest airport

Granbury Regional Airport (GDJ)

Coordinates

32.4361, -97.8133

Aircraft

Piper PA-28-140

Registration

N9898W

Category

Airplane

Year built

1967

Engines

1

Operator

Iron Compass Aviation

Operating rule

Part 91: General Aviation

Purpose of flight

Instructional

Phase of flight

Not recorded

Route

Granbury → Waco

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

CEN14LA334

Nobody was injured.

The partial loss of engine power due to the failure of the exhaust valve.

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

Read the full NTSB narrative

The flight instructor reported that, after takeoff, when the airplane was about 500 ft above ground level, the engine started to run roughly and lose power. The engine rpm decreased to about 1,100 rpm as the flight instructor attempted to turn the airplane 180 degrees back toward the airport. However, he was unable to land at the airport, so he made a forced landing to a field short of the runway. During a postaccident engine test run, the engine initially ran roughly, and black smoke was observed coming from the exhaust. After a brief warmup, the engine could only produce about 1,600 rpm at full throttle, and the engine test run was stopped. The examination of the No. 3 cylinder revealed that the exhaust valve was broken in several pieces and that some fragments remained in the cylinder, which produced gouging and scraping to the piston and cylinder head. The broken exhaust valve, spring, exhaust valve keepers, and rotating cap exhibited carbon buildup. Examination revealed a wear pattern on the top of the No. 3 cylinder exhaust valve rotator cap consistent with rocker arm wear. No rotational signatures were observed along the edge of the cap near the heavy carbon buildup, indicating that the rotator cap had stopped rotating, which subsequently led to a hot spot on the exhaust valve and caused the valve to fail.

Quoted verbatim from the NTSB record.