Accident American Aviation AA-1A N9394L,
ASN logo
ASN Wikibase Occurrence # 385358
 
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:Wednesday 11 October 2000
Time:06:14 LT
Type:Silhouette image of generic AA1 model; specific model in this crash may look slightly different    
American Aviation AA-1A
Owner/operator:Shaw Aviation, Inc.
Registration: N9394L
MSN: AA-1A-0094
Total airframe hrs:2937 hours
Engine model:Lycoming O-235C
Fatalities:Fatalities: 0 / Occupants: 1
Aircraft damage: Substantial
Category:Accident
Location:Philadelphia, PA -   United States of America
Phase: En route
Nature:Survey
Departure airport:Philadelphia, PA (KPNE)
Destination airport:
Investigating agency: NTSB
Confidence Rating: Accident investigation report completed and information captured
Narrative:
The airplane was on a traffic observation flight when it experienced a total loss of engine power. The pilot performed a forced landing to a schoolyard and escaped uninjured. Initial examination revealed heat damage to the #4 cylinder and no oil in the engine. Removal of the #4 cylinder revealed a hole in the #4 piston at the 12 o'clock position beneath the piston ring lands. The hole carried through to the interior of the piston. Removal of the #2 cylinder revealed that the #1 connecting rod was separated from the crankshaft. In addition to the hole through the #4 piston, examination revealed a deep groove in the side of the piston in line with the forward piston pin plug. The plug was worn and heat damaged, with significant material loss. Material transfer in line with the piston plug was observed on the wall of the #4 cylinder. The oil-scraper piston rings on the #1 and #2 pistons were installed backwards. The #3 cylinder had 3 base nuts installed upside down. Examination of the #1 and #2 cylinder assemblies revealed they were Superior cylinders. The number #3 and #4 cylinder assemblies were reworked Lycoming cylinders. The individual piston part numbers could not be determined. Examination of the maintenance records revealed the owner/operator replaced the #3 and #4 cylinder assemblies 337 aircraft hours prior to the accident. The owner/operator serviced the engine with 80 weight oil, and returned the airplane to service. The #1 and #2 cylinder assemblies were replaced by a maintenance facility 235 aircraft hours prior to the accident, and the engine was serviced with mineral oil as recommended by the engine manufacturer.

Probable Cause: A hole in the #4 piston for undetermined reasons which resulted in engine oil starvation and engine stoppage.

Accident investigation:
cover
  
Investigating agency: NTSB
Report number: IAD01LA002
Status: Investigation completed
Duration: 2 years and 10 months
Download report: Final report

Sources:

NTSB IAD01LA002

Location

Revision history:

Date/timeContributorUpdates
04-Apr-2024 17:41 ASN Update Bot Added

Corrections or additions? ... Edit this accident description

The Aviation Safety Network is an exclusive service provided by:
Quick Links:

CONNECT WITH US: FSF on social media FSF Facebook FSF Twitter FSF Youtube FSF LinkedIn FSF Instagram

©2024 Flight Safety Foundation

1920 Ballenger Av, 4th Fl.
Alexandria, Virginia 22314
www.FlightSafety.org