This is something I had been wondering about so I was glad to see this follow up story.
Davis died after failing to tense abs to counter G-forces
By Chris Amos - Staff writer
Posted : Tuesday Jan 15, 2008 8:07:13 EST
A crash that killed a Blue Angels pilot during an air show April 21 was caused by a Navy pilot making a sharper-than-normal turn to catch up with his five squadron mates and then failing to take steps to prevent blood from rushing from his brain during the maneuver, according to a report released Monday.
Lt. Cmdr. Kevin Davis, flying in his seventh Blue Angels show, was attempting to rejoin a formation at the end of a Blue Angels performance when he crashed his F/A-18 into a wooded residential area about three miles west of Marine Corps Air Station Beaufort, S.C.
Those forces caused by the maneuver — 6.7 Gs — were within the range expected for that maneuver, but their quick onset left Davis temporarily disoriented.
Navy officials say the squadron’s culture of perfection contributed to the crash.
“The culture of the Naval Flight Demonstration Squadron is that they constantly strive to perform a perfect show, every show,” the investigating officer, Lt. Col. Javier Ball, wrote in his report. “I believe that Lieutenant Commander Davis was simply trying to meet this standard, just as he would have at any other show.”
Investigators say Davis compounded his error by failing to flex his abdominal and leg muscles to keep blood from rushing away from his brain, as all tactical aviators are trained to do, investigators said. Failing to do so can lead to loss of consciousness, also known as blacking out, or loss of space and time perception, which they believe Davis experienced, known as a “grayout.”
Investigators say they believe Davis never lost consciousness because he maintained control of the Hornet’s control stick until impact, attempting to right the aircraft until it struck the ground at nearly 350 miles per hour.
Davis was found at the end of a debris field that extended several hundred feet. Rescue workers arrived within four minutes and attempted to revive him, but he was pronounced dead at the scene minutes later.
Witnesses said metal and plastic wreckage — some of it on fire — hit homes in a residential area about 35 miles northwest of Hilton Head. Eight people on the ground suffered non-life-threatening injuries.
Davis, 32, of Pittsfield, Mass., had been an F/A-18 pilot since 1999 and had logged more than 1,900 hours in the Hornet, including deployments aboard the carriers Dwight D. Eisenhower and John F. Kennedy and extended operations in the Persian Gulf in support of Operation Enduring Freedom. He worked as a Navy adversary pilot before joining the Blue Angels in September 2005.
Capt. Jack Hanzlik, spokesman for the chief of navy personnel, said he had performed more than 100 training flights with the Blue Angels — including the exact maneuver that led to the crash.
The Blue Angels were grounded for nearly a month while investigators studied the crash.
Before Davis’ death, the most recent Blue Angels fatal crash was in 1999, when a pilot and crew member died while practicing for air shows at a base in Georgia. An investigation determined that the pilot likely developed tunnel vision because a recent rib injury kept him from flexing his abdominal muscles.
After the 1999 crash, the Navy’s air training chief ordered the Blue Angels to consider wearing G-suits, which automatically inflate around a pilot’s legs and lower torso to prevent blackouts during tight maneuvering. Most tactical pilots wear them, but the Blue Angels do not because their sudden inflation could cause a pilot to accidentally bump the control stick — a potentially deadly move when flying inches from other planes during training and performances.
Since the 1999 crash, the Blue Angels pilots have received a series of waivers that allow them to fly without G-suits. Those waivers, investigators recommend, should continue.
Hanzlik said investigators recommended a number of steps be taken to prevent a similar accident in the future.
Those recommendations included ordering Blue Angels pilots to complete mandatory weight training — after studies found that 10 to 12 weeks of training focused on muscles used during “anti-G straining maneuvers” can lead to a 50 percent decrease in blackouts — and yearly centrifuge training geared to the unique stresses Blue Angels pilots endure. They also proposed developing a G-suit that could inflate without risk of bumping the control stick and looked at relaxing time standards for certain parts of the show to take some pressure off pilots.
But the best way to prevent these accidents, Hanzlik said, is to properly use the straining maneuvers.
“If you don’t properly perform this procedure, it can lead to a fatal impact,” he said.