PENSACOLA, Fla. --- A Navy Blue Angels pilot became disoriented and crashed after failing to properly tense his abdominal muscles to counter the gravitational forces of a high-speed turn last year, military investigators said Monday.

The report obtained by The Associated Press blamed the April 21 crash on an error by Lt. Cmdr. Kevin Davis, who died when his F/A 18 Hornet went down in a residential area near a Marine Corps station in Beaufort, S.C. Lt. Cmdr. Davis was in his first season flying in formation with the Navy's elite aerial demonstration team.

"In his final turn to attempt to rendezvous with the other Blues, he put a very fast, high-G turn on the aircraft. A real aggressive turn," said Capt. Jack Hanzlik, a Navy spokesman and former aviator.

An investigator reviewing flight data found that Lt. Cmdr. Davis never lost total control of the flight stick in the turn at six times the force of gravity. A temporary drop in blood flow to his brain caused by the gravitational pull likely caused him to experience tunnel vision and become disoriented, the report found.

"Kevin had performed these maneuvers in training and in the fleet. He had done them in similar situations and he had a history of performing them well without any problems," Capt. Hanzlik said.

The AP obtained the report as the result of Freedom of Information Act request.

The Pensacola-based Blue Angels fly without the traditional G-suits that most fighter pilots wear to avoid blacking out during maneuvers that exert strong gravitational forces. The suits inflate and deflate air bladders around the lower body to keep blood in the brain and heart.

The air bladders can cause a pilot to bump the control stick, so the Blue Angels instead learn to manage the forces by tensing their abdominal and leg muscles.

The report by Marine Lt. Col. Javier J. Ball recommended that the team consider wearing G-suits but states that wearing a suit would not have prevented Lt. Cmdr. Davis' crash. The suits only guard up to 1.5 times the force of gravity, the report stated.

Lt. Cmdr. Davis worked to regain control of the jet as it crashed.

"We can tell from the attempt to roll left and pitch up ... just prior to impact that he did not let go of the flight controls and, in the last few seconds he may have been aware of his low altitude and was attempting to save the aircraft," Lt. Col. Ball wrote.

The crash at Marine Corps Air Station Beaufort was the Blue Angels' first since 1999 and the 26th fatality in the team's 60-year history.

Because of the crash, the Navy has increased its exercise requirements for Blue Angels pilots with an additional focus on the abdominal and leg-muscle groups. The team has also stepped up its requirements for centrifuge training tailored for Blue Angels pilots.

The report said the demonstration team violated naval policy because it had allowed a waiver permitting its pilots to fly without G-suits to expire in 2005. Lt. Col. Ball called the expiration "a lack of careful attention to operating requirements." Navy officials extended the waiver after the Beaufort crash.

The Air Force Thunderbirds demonstration team members use G-suits in their F-16s, but the report noted that side-mounted controls in their cockpits allow the pilots to wear G-suits.

Lt. Cmdr. Davis' crash happened as the team was performing its final maneuver during the air show, with his parents watching. The team's six pilots were joining from behind the crowd of thousands to form a triangle shape known as a delta, but Lt. Cmdr. Davis did not join the formation.

Moments later, his jet crashed just outside the air station, hitting homes in a neighborhood about 35 miles northwest of Hilton Head Island, S.C. Debris -- some of it on fire -- rained on homes. Eight people on the ground were injured.

Through the Navy, members of the Davis family said they did not want to comment on the report.

In a statement, Cmdr. Kevin Mannix, the Blue Angels' commanding officer, called Lt. Cmdr. Davis a "superb naval officer and a great friend."

A decorated pilot who joined the Blue Angels in 2005, Lt. Cmdr. Davis had previously served as a narrator for the air shows. He also handled celebrity flights.

He graduated with honors in 1996 from Embry Riddle Aeronautical University in Daytona Beach, according to the Blue Angels' Web site. That September, he entered officer candidate school at the Naval Air Station in Pensacola.

He earned "Top Stick" status in his class at Fighter Squadron 101 at Naval Air Station Oceana, Va., while training in F-14 Tomcat jets. He flew missions supporting the U.S.-led war in Afghanistan and graduated from Navy Flight Weapons School in 2004.