SAN DIEGO (AP) – An improperly installed filter cap contributed to a Marine Corps helicopter crash at a California base that killed the Marine pilot and her co-pilot after the transmission seized, but authorities stopped short of say there was any wrongdoing, according to a report by military investigators.

The Marine Corps Times in a story Sunday detailed the report of the probe into the Jan. 23 accident near the Twentynine Palms base that killed the pilot, Maj. Elizabeth Kealey, and the co-pilot, Capt. Adam Satterfield. The newspaper obtained the report through a Freedom of Information Act request.

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At the time, Kealey was a captain and Satterfield a first lieutenant assigned to Marine Light Attack Squadron 169. Both were posthumously promoted.

Officials at Twentynine Palms on Monday said no one was available to comment on the investigation’s findings.

Investigators cited numerous missteps, including an improperly installed filter cover three days before the crash that allowed the transmission to dump its oil during the flight.

About 34 minutes into the 49-minute flight, the oil pressure gauge fluctuated and plummeted to zero but the pilots assumed the problem was due to a faulty gauge – not actual fluid loss – and decided to continue flying, according to the newspaper. Investigators say they calmly reported the fluctuating gauge to technicians and passed by two airports before the transmission would freeze, roughly 15 minutes from being warned of a problem.

The UH-1Y Venom helicopter plummeted within about 400 hundreds of yards of the intended landing site, according to the report.

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Maj. Gen. Michael Rocco, the commanding general of 3rd Marine Aircraft Wing, in endorsing the investigation’s report wrote that Kealey and Satterfield were “in the line of duty and were not due to their own misconduct.”

Investigators said in the report that they do not recommend punitive action be taken against any member of the squadron, but that preventative measures should be implemented to ensure filter caps are sealed in place correctly.

Kealey, 32, of Indiana, Pennsylvania, was commissioned in 2005 and had earned several awards and medals. She was deployed once in Afghanistan. Satterfield, 25, of Oldham, Kentucky, was commissioned in 2011 and supported training operations in Southern California.

Both pilots were based at Camp Pendleton.


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