Capt. Christopher Stover, of Vancouver, Washington, was piloting the Pave Hawk helicopter when it came down on Jan. 7 in a marshland nature reserve during a low-level training mission, The Columbian reported. He and the other three men aboard all died.
In a report issued last week, investigators said at least one goose hit the front of the helicopter, disabling its flight path stabilization systems.
Also killed in the crash were Capt. Sean M. Ruane, Tech. Sgt. Dale E. Mathews and Staff Sgt. Afton M. Ponce.
The lead helicopter crew didn't report seeing any birds as it passed over Cley Marshes in the Norfolk Wildlife Trust but the waterfowl were likely startled by the aircraft.
Stover was piloting the second helicopter in a low-level training exercise that involved a simulated rescue of an F-16 pilot who had ejected from his jet. Both air crews were wearing night-vision goggles.
Flying at 126 mph over a moonlit English coast, Stover's craft was about 110 feet above the ground when it was struck by the geese.
"The types of geese that hit the (aircraft) weigh between 6 and 12 pounds. A bird weighing 7.5 pounds would impact with 53 times the kinetic energy of a baseball moving at 100 mph," said the report, which was signed by Brig. Gen. Jon Norman, president of the investigation board,
While the report is primarily an account of a disaster, it also contained a tribute to the four aviators. Stover flew 100 rescue missions during a 3 1/2-month deployment to Afghanistan in 2012.