The commander of the Navy's Blue Angels flying ace team resigned from that position yesterday after citing "personal training difficulties" that he feared were distracting the elite unit. Its air shows have been canceled through mid-June, and maybe for the rest of the summer.

Cmdr. Donnie Cochran's resignation comes eight months after he suspended several of the Blue Angels' performances last year because he concluded his flying performance was not adequate and could have threatened other pilots and even members of the public.

Cochran, 41, was the first African American to join the aerial daredevil team as a pilot and the first to become its leader, in November 1994. Navy officials have said in the past that some white pilots had grumbled about his skills as an aviator and had said he got the job because he's black -- an assertion Navy officials denied.

"As commanding officer, Cochran understood that safety is paramount, and was concerned that his difficulties were beginning to impair the viability of the demonstration," said a statement yesterday by the Blue Angels unit. "Even the slightest decline in flying proficiency is detrimental to safety, especially given the precision with which the team performs.

"Commander Cochran believes his voluntary departure from the team is in the best interest of the U.S. Navy and the Blue Angels," added the unit's statement. The Blue Angels, formally known as the Navy's Flight Demonstration Unit, are based at the Naval Air Station in Pensacola, Fla.

The unit said it almost certainly will cancel its next three air shows -- in Tennessee, Massachusetts and Oklahoma -- and possibly more after that during its peak summertime performance season. In the Washington area the Blue Angels performed last week at Naval Academy graduation ceremonies at Annapolis, and one week before that at Armed Forces Day at Andrews Air Force Base.

The team's six pilots, drawn from the most proficient Navy and Marine fliers, perform precise, heart-stopping turns in tight formation at high speed. Their approximately 20 shows a year routinely draw crowds of 100,000 or more.

The command is one of the most prestigious for Navy aviators, and is a major part of the maritime service's marketing program. The Navy has boasted about Cochran during his term, in part, Navy officials have said, because they felt he could help recruit blacks to the Navy and in particular to the mostly white ranks of Navy aviators.

Last September Cochran, who is from Pelham, Ga., suspended the team's performances, and led it back into intensive training, after he became concerned he was not flying at peak performance, Navy officials said.

The Blue Angels must fly a series of maneuvers in tight sequence, in which, for example, several jets converge on a single point from several directions. Before each show, the Angels choose local landmarks, or "marks," to orient themselves.

Preparing for a show at Oceana Naval Air Station in Virginia Beach last September, the team had agreed on two runways as their mark. But Cochran missed his mark, causing the other pilots to adjust to his error, Navy officials said at the time.

"He did make some mental mistakes in the show, mistakes which alarmed him and which caused him to terminate the rest of the performance," Lt. John Kirby, spokesman for the team, said last year. "In that particular maneuver, was safety impaired? It could have been, but it wasn't necessarily."

Kirby and other members of the Blue Angels did not respond to a message left at their office in Pensacola yesterday evening.

Other Navy officers said that given his misgivings about his performance, Cochran should be praised for stepping down voluntarily.

"He's a stand-up guy, and he concluded he had to act to ensure there was the utmost confidence in every pilot's performance," a Navy official said yesterday. "This level of flying has to be almost instinctive. You can't be thinking through moves. It's a level of flying attainable by few people." CAPTION: The Blue Angels perform precise maneuvers, like above, at high speed.