'Up-and-Comer' in Missile Defense Agency Died Following Air Force C-17 Testing Mishap

A civilian employee with the Missile Defense Agency died last year after experiencing decompression sickness aboard an Air Force C-17 during a missile testing flight, an accident investigation revealed.

The Air Force released the investigation findings into the Aug. 21 incident on Friday, which disclosed the 33-year-old employee was "performing duties inherent to his role in the back of an aircraft following a test drop" at Joint Base Elmendorf-Richardson in Alaska, or JBER, "when he developed symptoms consistent with decompression sickness," Air Mobility Command said in a press release. The name of the man was withheld from the release and the report.

"Onboard physiological technicians responded to the individual and aircrew arranged for follow-on treatment upon landing at JBER," Air Mobility Command said. "Despite intervention efforts by qualified medical personnel, the individual's health continued to deteriorate upon arrival at the JBER emergency room, and the individual went into cardiac arrest prior to being transported to a higher echelon of care."

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The accident investigation board determined that "decompression sickness induced by the high-altitude, unpressurized portion of the military test mission" as well as the "pre-existing and underlying medical conditions" of the employee led to his death a day later at the hospital on Aug. 22.

"He was extremely proud of his family and frequently shared pictures of them with other crew members both leading up to and on the actual flight," the report detailed. "The [deceased employee] was recognized for his expertise in this mission set [and] had been identified as an 'up-and-comer' with the Missile Defense Agency."

News of the Missile Defense Agency employee's death last year comes as another recently released accident report showed that a civilian contractor was also killed while doing testing on an MQ-9A drone.

Stephanie R. Cosme, 32, died on Sept. 7 after "she inadvertently walked into the parked remotely piloted aircraft's rotating propeller" during testing at Gray Butte Airfield near Edwards Air Force Base in California, Air Force Materiel Command said in a press release earlier this month.

Cosme was employed by Sumaria Systems, LLC, and provided test support services for the Air Force Life Cycle Management Center, Detachment 3, the service said. She died shortly after being airlifted to a local hospital.

"At the time of the mishap, the Sumaria Systems contractor team was providing engineering and professional test support to evaluate electromagnetic interference/electromagnetic compatibility testing with a new release of MQ-9A software on payloads and other aircraft systems," the Air Force said.

The accident investigation board president said the test engineer was incorrectly taught how to take telemetry readings near the MQ-9A while the engine was running and she also "lost situational awareness" when taking readings with a handheld device, the service said.

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