ASN Wikibase Occurrence # 137272
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: | Tuesday 5 July 2011 |
| Time: | 17:00 |
| Type: |  Piper J3C-65 Cub |
| Owner/operator: | Private |
| Registration: | N98550 |
| MSN: | 18763 |
| Year of manufacture: | 1946 |
| Total airframe hrs: | 1776 hours |
| Engine model: | Continental A&C65 SERIES |
| Fatalities: | Fatalities: 0 / Occupants: 2 |
| Aircraft damage: | Substantial |
| Category: | Accident |
| Location: | Egremont, near Great Barrington Airport - KGBR, MA -
 United States of America
|
| Phase: | Landing |
| Nature: | Private |
| Departure airport: | Great Barringto, MA (GBR) |
| Great Barringto, MA (GBR) | |
| Investigating agency: | NTSB |
| Confidence Rating: |  Accident investigation report completed and information captured |
The pilot reported that the accident flight was the first flight in the airplane in 6 months. During the initial climb, the engine experienced a partial loss of power. The pilot checked the magnetos and carburetor heat but was unsuccessful in his attempts to regain full engine power. Subsequently, he chose to land the airplane between two houses. A postaccident engine compression test revealed that the Nos. 1 and 4 cylinders had low compression. The No. 1 rocker cover was removed, and the rocker arm was tapped with a mallet, which brought its compression to within normal range. Disassembly of the No. 4 cylinder revealed that it was leaking past the exhaust valve and through the exhaust system. In addition, disassembly revealed a scored intake valve stem and valve guide. The intake valve would not operate and had to be forcefully removed from the valve guide. According to the engine overhaul manual, scored valve stems can cause the engine to produce low power. The pilot did not report performing any of the procedures to return the engine to service from indefinite storage (that is, more than 90 days). Therefore, it is also likely that the engine was never prepared for indefinite storage and, thus, was not stored improperly for the 6 months it was not used before the accident flight. During storage, the No. 4 intake and exhaust valves most likely became lodged in the valve guides, which resulted in a partial loss of engine power and subsequent forced landing to a field. It is likely that, if the engine had been properly stored, the recommended lubrication would have prevented the valves from sticking and scoring and that, if the engine had been properly removed from storage, the scored valves may have been detected and replaced, either of which action could have prevented the accident.
Probable Cause: A partial loss of engine power due to the No. 4 intake and exhaust valves becoming lodged in the valve guides, which resulted from a lack of use, improper engine storage preparation, and improper return to service from indefinite storage.
Accident investigation:
 |
|
Sources:
NTSB
History of this aircraft
Other occurrences involving this aircraft
| 13 August 2017 | N98550 | Berkshire Aviation Enterprises Inc | 0 | Salisbury, CT | |
sub |
| Maintenance issues | ||||||
Location
Revision history:
| Date/time | Contributor | Updates |
|---|---|---|
| 06-Jul-2011 01:27 | gerard57 | Added |
| 06-Jul-2011 02:53 | RobertMB | Updated [Time, Aircraft type, Location, Phase, Departure airport, Destination airport, Source, Damage, Narrative] |
| 06-Jul-2011 08:11 | RobertMB | Updated [Time, Aircraft type, Registration, Cn, Operator] |
| 21-Dec-2016 19:26 | ASN Update Bot | Updated [Time, Damage, Category, Investigating agency] |
| 27-Nov-2017 17:01 | ASN Update Bot | Updated [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