Casualties unknown

2005-06-21: Cessna 320E (N3438Q) — Map Inc. — Missoula, MT

Missoula, MT, US

On June 21, 2005, a Cessna 320E (registration N3438Q) operated by Map Inc. was involved in an aviation accident near Missoula, MT. Investigators recorded the probable cause as: The engine power loss was caused by pieces of an air filter instructional sheet becoming lodged between the turbocharger impeller and its housing. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 1781061362Data APIEditorial standards

A twin-engine aircraft experienced a right engine power loss shortly after takeoff, leading to an impact with a hill and subsequent post-crash fire.

What happened

During the preflight inspection and engine runups, the pilot reported no anomalies with the aircraft. The takeoff proceeded normally until the aircraft reached approximately 100 to 200 feet above the ground, at which point the right engine lost power.

The pilot feathered the right propeller, secured the engine, and established a left bank into the operating engine, allowing the aircraft to begin a slow climb. In an effort to avoid trees, the pilot turned approximately 25 degrees to the left toward a field. However, because of the loss of altitude experienced during the initial engine failure, the aircraft was positioned below the crest of a hill and could not clear it. The Cessna (type not specified in source) impacted the hill in a nose-high attitude with the right wing low. Following the impact, the aircraft was consumed by fire; however, both the pilot and the passenger not injured and were able to egress the aircraft safely.

The investigation

During the post-accident recovery of the right engine, investigators found that the turbocharger had separated from the engine during the impact sequence. Inside the turbocharger, pieces of paper were discovered lodged between the impeller and the housing. Upon examination, these papers were identified as an air filter instructional sheet.

Records indicated that a replacement air filter had been installed on the right engine approximately four months prior to the accident, after which the aircraft had flown about 54 hours. An inspection of a new, packaged filter showed that such instruction sheets and stickers are placed inside the filter canister before being bagged. The investigation determined that the instructional paper had remained in the assembly.

Probable cause

The engine power loss was caused by pieces of an air filter instructional sheet becoming lodged between the turbocharger impeller and its housing.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20050623X00862. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.