The crash of a Marine aircraft in Hawaii that killed two Marines from a Camp Pendleton unit and injured 20 others was caused when the pilots attempted a landing during a "severe brownout condition" with the air thick with dust and sand, according to the Marine Corps.
The MV-22 Osprey crashed May 17 during predeployment training at Bellows Air Force Base for the Camp Pendleton-based 15th Marine Expeditionary Unit.
Killed were Lance Cpl. Joshua Barron, 24, of Spokane, Wash., and Lance Cpl. Matthew Determan, 21, of Ahwatukee, Ariz. Barron was an Osprey crew chief; Determan was an infantry rifleman.
The Osprey is a tilt-rotor aircraft that can take off like a helicopter and fly like an airplane.
"The pilots did not violate any regulations or flight standards," according to a statement released Monday by the Hawaii-based Marine Corps Forces Pacific.
Still, the pilots should have realized that their visibility reduction "was much higher than anticipated" and then chosen "an alternate flight profile, path, or landing site that would have minimized or avoided the severe brownout conditions," the statement said.
Sand and dust "caused a buildup of material on the turbine blades and vanes" that led an engine to stall and put the aircraft into "an unavoidable freefall to the ground," the statement said.
After the engine stalled, the air crew "performed all emergency procedures" but the Osprey burst into flames after a hard landing.
More Marines might have been killed except for the "heroic, selfless actions of the Marines and sailor aboard the aircraft," along with military and civilian emergency personnel, the statement said.
The statement followed the completion of an investigation into the crash.
Recommendations in the investigation report "include the potential for disciplinary and administrative actions," the statement said.
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