ASN Wikibase Occurrence # 143824
This information is added by users of ASN. Neither ASN nor the Flight Safety Foundation are responsible for the completeness or correctness of this information.
If you feel this information is incomplete or incorrect, you can submit corrected information.
| Date: | Friday 17 February 2012 |
| Time: | 16:52 |
| Type: |  Cessna 172N Skyhawk |
| Owner/operator: | Private |
| Registration: | N4737D |
| MSN: | 17272345 |
| Year of manufacture: | 1979 |
| Total airframe hrs: | 1557 hours |
| Engine model: | Lycoming 0-320 SERIES |
| Fatalities: | Fatalities: 0 / Occupants: 1 |
| Aircraft damage: | Substantial |
| Category: | Accident |
| Location: | Route 13, Powhatan, VA -
 United States of America
|
| Phase: | En route |
| Nature: | Private |
| Departure airport: | Manassas, VA (HEF) |
| Fayetteville, NC (FAY) | |
| Investigating agency: | NTSB |
| Confidence Rating: |  Accident investigation report completed and information captured |
According to the pilot, while in cruise flight, the engine began to lose power. He noticed a vibration in the throttle control and an “oily” smell. Engine power decreased to 1,500 rpm. The airplane was unable to maintain altitude, and the pilot elected to make an emergency landing in a field. During the landing roll, the airplane collided with an embankment and sustained substantial damage to the fuselage. An examination of the engine revealed that the No. 4 valve spring seat had broken. A review of the maintenance records revealed that the engine had accumulated 1865.34 hours since the last overhaul 6.5 years before the accident. According to Lycoming Service Instruction 1009AU, the recommended time between overhaul is 2,000 hours or 12 years, whichever occurs first. Further review of the maintenance records revealed compliance with Airworthiness Directive 80-04-03 R2, which covers the replacement of the upper exhaust valve spring seats and the exhaust hydraulic lifters. The exhaust valve seat failed 134.66 hours before the next recommended overhaul. The investigation was unable to determine the reason for the valve seat failure.
Probable Cause: The partial loss of engine power due to the failure of the exhaust valve spring seat for reasons that could not be determined.
Accident investigation:
 |
|
Sources:
NTSB
Location
Revision history:
| Date/time | Contributor | Updates |
|---|---|---|
| 18-Feb-2012 01:01 | Alpine Flight | Added |
| 21-Feb-2012 19:26 | Geno | Updated [Source] |
| 01-Mar-2012 10:46 | Geno | Updated [Time, Source, Damage, Narrative] |
| 21-Dec-2016 19:26 | ASN Update Bot | Updated [Time, Damage, Category, Investigating agency] |
| 27-Nov-2017 20:19 | ASN Update Bot | Updated [Operator, Other fatalities, Departure airport, Destination airport, Source, Narrative] |
Corrections or additions? ... Edit this accident description
The Aviation Safety Network is an exclusive service provided by:
Quick Links:
| ASN Home | Send Correction / Feedback |
| FSF Home | Disclaimer | Copyright |
| Contact Us | Privacy Policy |
| Press / Media |
CONNECT WITH US:
©2024 Flight Safety Foundation