Disorientation and reduced visibility were factors in the death of a U.S. Air Force pilot who crashed his F-15C fighter jet off the coast of England earlier this year, service officials said in a statement Monday.
Air Force 1st Lt. Kenneth Allen, 27, with the RAF Lakenheath-based 48th Fighter Wing, was killed after his plane plunged into the North Sea about 140 miles northeast of the base on June 15.
An Air Force accident investigation board determined that the crash was the result of "the pilot's fixation on the intercept of the simulated adversary aircraft and failure to execute cockpit instrument visual scans" while flying through cloud cover and experiencing spatial disorientation, the report said.
The weather in the airspace at the time was reported to have multiple cloud layers up to 25,000 feet. Other pilots in the vicinity said the horizon was "difficult if not impossible to discern below" 9,000 feet, according to the report.
Allen, was considered an inexperienced pilot with about 271 total flight hours, including more than half in the F-15C simulator.
On the day of the crash, he was participating in routine training, flying as the No. 4 jet in a four-against-six air-to-air exercise.
While flying east at 20,300 feet, Allen was directed to make a hard-right turn back toward the west and look for the adversary aircraft at a lower altitude, the report said.
Allen made the turn and simulated a missile shot against the other aircraft and continued his descent to 12,000 feet. When told his simulated strike was a probable miss, Allen entered a steep diving left turn to intercept the aircraft, descending at one point to a vertical velocity of 38,800 feet per minute, the report said.
At about 1,000 feet, Allen maneuvered his aircraft to nearly wings-level and pulled 8.2 G-forces in an apparent attempt to recover his jet above the water, the report said.
In his findings, board president Maj. Gen. Dean Tremps said it appeared Allen was focused on intercepting the other aircraft either visually or with his radar "and did not monitor his aircraft altitude, airspeed and attitude cockpit instruments."
As he exited the low cloud layer at about 1,000 feet with a "visible horizon and ‘ground rush' of the rapidly approaching ocean," he sensed his position and tried to recover the aircraft, but was unable due to his speed and altitude, Tremps wrote in his opinion summary.
Allen's "fixation on his intercept" of the other aircraft and failure to use his cockpit instrument visual scans caused the mishap, Tremps said, with reduced visibility and lack of a discernible horizon resulting in spatial disorientation.
Allen hit the water at about 651 miles per hour. Tremps said there was no evidence that he attempted to eject, though he was at too low of an altitude for a successful ejection.
The aircraft, valued at an estimated $45 million, was destroyed.
A search and rescue effort, hampered by poor visibility near the crash site, was launched by U.S. Air Force and United Kingdom coast guard and navy assets.
About two hours after the crash, teams located an oil slick and the pilot's shredded life raft. Other items recovered from the debris field included the pilot's survival kit and unopened parachute. Allen's body was recovered the same day, the report said.
The report ruled out aircraft malfunction, component failure and maintenance issues as contributing factors to the crash.
"Lt. Allen was an outstanding officer and a tremendous asset to the team," Gen. Jeff Harrigian, U.S. Air Forces in Europe and Air Forces Africa commander, said in a statement. "No words can compensate for such a painful and sudden loss."
The commander of the 48th Fighter Wing, Col. Jason Camilletti, said the wing and especially Allen's 493rd Fighter Squadron were "truly touched by the tremendous outpouring of support from families, friends and partners around the globe in our time of grieving."
This story has been updated.