Two weeks after being ousted, Air Force Secretary Michael Wynne said Friday he had a "difference in philosophy" with his boss, Defense Secretary Robert Gates, on numerous issues -- not just on the nuclear slip-up that Gates said was his reason for removing Wynne.

On his final day in office, a relaxed-looking Wynne told a group of reporters that he is not angry about being forced out as the top civilian official of the Air Force. He defended his record, saying he had "pushed the system pretty hard" to ensure that the Air Force is at the leading edge of warfighting.

He indicated no animosity toward Gates, with whom he said he was "not aligned" on some key issues.

"When you have a difference of philosophy with your boss, he owns the philosophy and you own the difference," he said.

Wynne, who took office Nov. 3, 2005 after serving as the Pentagon's top weapons buyer, is being replaced by Michael Donley, who will hold the job as the acting secretary pending Senate confirmation as the permanent replacement.

Beyond matters of philosophy, Wynne said he and Gates differed on future investment in the new-generation F-22 stealth fighter, on the extent of Air Force personnel cuts and other substantive issues.

"There were differences that accrued," Wynne said.

By coincidence, Wynne's exit came on the same week that the Air Force suffered yet another major setback -- a ruling by the Government Accounting Office that the service had made significant errors in awarding a $35 billion aircraft contract to Northrop Grumman and its European partner. The audit agency recommended that the Air Force reopen the bidding process.

Wynne likened that setback to the disappointment felt by a baseball player who made it to the World Series and then "struck out in the ninth inning" when the outcome of the game was at stake.

He indicated that the GAO ruling had rocked the Air Force and raised some tough questions internally. He also said it almost certainly means the Air Force will fail to put the planes into service starting in 2013, as planned.

"Of course the Air Force will try desperately to hold onto" that target date "because of the age of our (current) fleet," he said.

"I will also say there's almost no way to do that in the face of this straightforward delay in the start date," he added. He noted that Northrop has put off construction of two facilities that would build the aircraft.

Timing is an important issue because the current fleet of aerial refuelers is growing decrepit. The fleet of refuelers is a critical link in the global reach of the Air Force, enabling fighters and bombers to operate over great distances and to remain on station for long periods over Iraq, Afghanistan and elsewhere.

Wynne said he saw no possibility that the GAO could be made to alter its findings. And although its recommendation that the bidding be reopened is not binding on the Air Force, Wynne indicated that after studying the decision further, the Air Force likely would issue a new request for contract bids.

"We were very disappointed," by the decision, Wynne said in the Air Force's most extensive comments thus far on a GAO ruling that gives ammunition to Boeing supporters in Congress who have been seeking to block funding for the tanker deal or to force a new competition.

"The reason we are very disappointed I think is the intensity of effort that went into having a very open and a very transparent" competition between Boeing and Northrop, Wynne said. He spoke of "reshaping and revising" the competition, but he did not indicate that any final decisions had been made.

When he announced on June 5 that he was removing Wynne as well as Gen. Michael Moseley, the Air Force chief of staff, Gates said his decision was based mainly on the findings of a review of the Air Force's nuclear weapons mission by Navy Adm. Kirkland Donald, following two nuclear-related slip-ups.

The Donald report detailed the mistaken shipment to Taiwan of four Air Force electrical fuses for nuclear missile warheads. It also linked the underlying causes of that error to another startling incident: the flight last August of a B-52 bomber that was mistakenly armed with six nuclear-tipped cruise missiles. Donald concluded that the Air Force had let its nuclear focus deteriorate.

In the interview, Wynne did not explicitly take issue with Donald's findings but said the admiral, who is the Navy's leading expert on nuclear issues, "saw things a lot differently than the Air Force" does.

"In bringing a different eye to it, he evaluated us against criterion within the Navy and found some of the ways we do it (the nuclear mission) wanting, and I can appreciate that," Wynne said. He added that over the years the Air Force had become "a little bit less careful about the inventory control" of nuclear weapons and weapons-related components.