Poor crew coordination blamed in Apache crash
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The Army says 80 percent of its aviation accidents are caused by human error — and that most of those are sparked by poor crew coordination. That apparently was the case when a Boeing Co.-manufactured AH-64D Apache helicopter crashed in South Korea earlier this year, killing two experienced pilots. Capt. Dion Burmaz, 28, of Placentia, Calif., and Chief Warrant Officer Aaron Cowan, 37, a native of Silver City, N.M., died Feb. 26 during a routine training flight after their aircraft crashed into a mountainside. Both pilots were assigned to the 1st Battalion (Attack), 2nd Aviation Regiment, based in South Korea. The Army’s investigation found that poor crew coordination led to a crucial eight seconds during their daytime flight when neither pilot was in control of the aircraft, the advanced Longbow version of the Apache. Based on cockpit voice recordings and other data, investigators believe that each of the two pilots thought the other man was in control of the aircraft during that period. Both were looking at equipment inside the aircraft, with neither watching the mountainous terrain outside. “A well-trained, well-led, qualified and experienced aircrew failed to perform basic crew coordination duties within the cockpit,” the investigation found. “The lack of positive transfer of the flight controls resulted in an eight-second period with neither pilot on the controls or maintaining obstacle avoidance. This caused the aircraft to impact the ground.” The Apache carries two pilots, seated one behind the other, who routinely transfer control of the aircraft back and forth during a mission. Under Army guidelines, the pilots must go through a verbal handoff to ensure that control of the aircraft is properly transferred. Before handing off responsibility for flying the helicopter, the pilot who is flying is supposed to announce, “You have the controls,” to which the other responds, “I have the controls.” The pilot who initiated the transfer still is not supposed to transfer control until he announces once again, “You have the controls.” Those handoff procedures were not followed in the South Korea crash. Just before the crash, another Apache pilot called Burmaz, who was in the front seat, and Cowan, in the rear seat, and asked them whether they wanted the coordinates of a vehicle being used for target practice. Burmaz replied: “Yeah, go ahead. You have the controls.” Cowan responded: “I got it.” Investigators believe that Cowan was responding to the other Apache aircraft’s offer for coordinates but that Burmaz assumed Cowan had taken the flight controls. Cowan, meanwhile, believed that Burmaz was still flying the aircraft. Both pilots then diverted their eyes to look inside the helicopter. Burmaz began writing down the coordinates on his clipboard while Cowan input them into the helicopter’s computer. The last sound captured by the cockpit voice recorder is Cowan making “a surprised wooooahh sound” and attempting to increase the aircraft’s altitude, the investigation said. After being briefed by Army officials on the accident findings, Darko Burmaz, Dion’s father, said he finds it hard to believe that aircrew coordination — and not mechanical or design failure — was the cause of the crash. “These were two very capable pilots,” Burmaz said. “It just doesn’t make any sense.” In an effort to prevent similar aircrew coordination accidents, Tip and Mary Cowan, Aaron’s parents, are pressing Boeing and the Army to install a simple sensor on the Apache control stick that would sound an alarm if neither pilot has a hand on it. “Shouldn’t there be a positive, mechanical/electronic method of alerting the pilots when no one has the controls?” Tip Cowan wrote to Boeing board members. The company had not replied to him. Asked about the Cowans’ proposal, Carole Thompson, a spokeswoman for Boeing in Mesa, Ariz., said, “It is the Army, not Boeing, that determines the cockpit controls configuration for all its aircraft.” But Maj. Steven Van Riper, of the Army’s Combat Readiness Center, Fort Rucker, Ala., who led the accident investigation, sounded a positive note about the Cowans’ idea. “That is definitely a very interesting recommendation,” he said. Source : seattlepi.nwsource.com |