ASN logo
ASN Wikibase Occurrence # 45301
Last updated: 19 November 2019
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.

Type:Silhouette image of generic BE35 model; specific model in this crash may look slightly different
Beechcraft V35B Bonanza
Registration: N6432X
C/n / msn: D-10398
Fatalities:Fatalities: 2 / Occupants: 2
Other fatalities:0
Aircraft damage: Substantial
Location:Delaware City, DE -   United States of America
Phase: En route
Departure airport:Philadelphia, PA (LOM)
Destination airport:Columbia, SC (CAE)
Investigating agency: NTSB
The airplane was in cruise flight at 4000 feet msl, at night, when the pilot reported a partial loss of engine power. Air traffic control provided a vector to the nearest airport, about 8 miles north of the airplane's position. About 7 miles from the airport, at an altitude of approximately 1,000 feet, the pilot reported that he was not going to reach the airport. The airplane subsequently impacted terrain about 6 miles from the airport. Examination of the wreckage revealed an approximate 4-inch diameter hole on the top section of the crankcase, near the number two cylinder. Further examination of the engine at the manufacturer's facility revealed that a silicone sealant consistent with RTV was observed along mating surfaces where the cylinders attached to the case. The substance was also found on the through-bolts. The number two cylinder was found backed-off from the case. The engine case exhibited marks consistent with rubbing between the number two cylinder and the case. The number two piston ring had shattered. The number two piston skirt exhibited impact marks consistent with the skirt striking the case. The number two connecting rod exhibited elongated holes, consistent with an overstress failure, and the rod cap was not recovered. The top of the case exhibited two holes in the vicinity of the magnetos. A mechanic stated that he completed a top overhaul of the airplane engine about 3 months prior to the accident. The overhaul included the installation of six new cylinders. The mechanic reported that he added Permatex RTV (part number 27B) to the cylinder bases during engine assembly. The mechanic further stated that he had referred the manufacturer's service information letter regarding sealants, but it did not list RTV either pro or con. The mechanic stated that he did not refer to the manufacturer's service bulletin SB96-7B. That bulletin stated that the use of sealants or lubricants other than those specified by the manufacturer on mating threads and between mating surfaces can cause incorrect torque application and subsequent engine damage or failure.
Probable Cause: The mechanic's improper engine overhaul. A factor was the night condition.



Revision history:

28-Oct-2008 00:45 ASN archive Added
21-Dec-2016 19:24 ASN Update Bot Updated [Time, Damage, Category, Investigating agency]
08-Dec-2017 18:00 ASN Update Bot Updated [Source, Narrative]

Corrections or additions? ... Edit this accident description