Cessna 172N N5944J

Summary

On 27 April 2013 at about 22:00 local time, a Cessna 172N registered N5944J was involved in an accident near Dade City, Florida, United States. 3 people were on board and 3 had minor injuries. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

27 April 2013 at 22:00

Classification

Accident

Location

Dade City, Florida, United States

Coordinates

28.3604, -82.1903

Aircraft

Cessna 172N

Registration

N5944J

Category

Airplane

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Instructional

Phase of flight

Not recorded

Route

Hernando County → Fort Pierce

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

ERA13FA217

3 people had minor injuries.

The in-flight loosening of the No. 3 cylinder exhaust valve rocker arm stud, which resulted in a complete loss of engine power.

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

Read the full NTSB narrative

During the accident flight, the exhaust gas temperature on the No. 3 cylinder began as the coldest and then transitioned to the hottest. Subsequently, the cylinder head temperature on the No. 3 cylinder also transitioned to the hottest. According to the pilot, the engine then began to run roughly, and he adjusted the throttle and mixture positions to gain control of the malfunctioning engine. During emergency communications with air traffic control, the engine lost all power, and the pilot conducted an emergency landing to a field. Examination of the engine revealed that the No. 3 cylinder exhaust valve rocker arm stud had backed out of the cylinder, which prevented the exhaust valve from opening properly. Specifically, the loose rocker arm stud prevented the pushrod from depressing the exhaust valve far enough in to release exhaust from the cylinder, which damaged the intake valve pushrod and caused a complete loss of engine power. The No. 3 cylinder had been replaced about 14 months before the accident and had accumulated 480.9 hours since installation. It is likely that the rocker arm and nut assembly became loose over time; the initial torque value could not be determined.

Quoted verbatim from the NTSB record.