This October 2005 file photo shows a group of U.S. Air Force F-15 aircraft flying in formation near Mountain Home Air Force Base, Idaho. Air Force officials are warning that unless their annual budgets are increased dramatically between 2009 and 2013, the military's high-flying branch won't dominate the skies as it has in decades past.

Washington ? Air Force officials are warning that unless their budget is increased dramatically, and soon, the military’s high-flying branch won’t dominate the skies as it has for decades.

After more than seven years of war in Afghanistan and Iraq, the Air Force’s aging jet fighters, bombers, cargo aircraft and gunships are at the breaking point, they say, and expensive, ultramodern replacements are needed fast.

“What we’ve done is put the requirement on the table that says, ‘If we’re going to do the missions you’re going to ask us to do, it will require this kind of investment,”‘ Maj. Gen. Paul Selva, the Air Force’s director of strategic planning, said in an interview with The Associated Press.

“Failing that, we take what is already a geriatric Air Force,” Selva said, “and we drive it for another 20 years into an area of uncertainty.”

An extra $20 billion each year over the next five – beginning with an Air Force budget of about $137 billion in 2009 instead of the $117 billion proposed by the Bush administration – would solve that problem, according to Selva and other senior Air Force officers.

Yet the prospects for huge infusions of cash seem dim. Congress is expected to boost the 2009 budget, but not to the level urged by the Air Force. In the years that follow, a possible recession, a rising federal deficit and a distaste for higher taxes all portend a decline in defense spending regardless of which party wins the White House in November.

“The Air Force is going to be confronting a major procurement crisis because it can’t buy all the things that it absolutely needs,” said Dov Zakheim, a former Pentagon comptroller. “It’s going to force us to rethink, yet again, what is the strategy we want? What can we give up?”

The Air Force’s distress is partly self-inflicted, says Steve Kosiak of the Center for Strategic and Budgetary Assessments in Washington. The F-22 Raptor and F-35 Lightning, the new jet fighters that will supplant the F-15 Eagle and F-16 Falcon, have drastically higher price tags than their predecessors and require a bigger chunk of the defense budget.

“One of the reasons their equipment has aged so much is because they continue to move ahead with the development and presumed acquisition of new weapon systems that cost two to three times as much as the systems they are replacing,” Kosiak said. “It’s like replacing a Toyota with a Mercedes.”

It’s not as if the Air Force has gone without any new airplanes. The B-2 Spirit stealth bomber, the C-17 Globemaster airlifter and the CV-22 tilt-rotor, which flies like a helicopter or an airplane, have all been added since the mid-1990s.

The Air Force also is planning to spend between $30 billion and $40 billion over the next 15 years for new refueling tankers. A contract is expected to be awarded soon. Those new tankers, however, won’t be flying until 2013.

The Air Force isn’t alone in wanting more money, but its appetite is far greater than the other military branches. Shortly after President Bush submitted his defense plan for the 2009 budget year, which begins Oct. 1, each service outlined for Congress what it felt was left out. The Air Force’s “wish list” totaled $18.8 billion, almost twice as much as the other three services combined.

“There’s no justification for it. Period. End of story,” said Gordon Adams, a former Clinton administration budget official who specializes in defense issues. “Until someone constrains these budget requests, the hunger for more will charge ahead unchecked.”

Current F-15s and F-16s are on average more than 20 years old and have reached a point where spending more money on extensive repairs is a poor investment, Selva said. Originally designed to last 4,000 flying hours, both have been extended beyond 8,000.

An F-15 with a comparatively low 5,000 flying hours disintegrated during a routine training flight over Missouri in early November. For the Air Force, that crash has become a touchstone event that demonstrates the precarious state of a fleet collectively older than any in the service’s 60-year history.

Following the Missouri accident, more than 400 F-15s were grounded as Air Force mechanics scoured them for defects that might cause a similar accident. The F-15, a twin-engine jet with a top speed of 1,875 miles per hour, is the anchor of the nation’s air defense network.

As aircraft age, corrosion eats away at metal parts. Wiring and sealing begin to deteriorate. The fatigue, which can be hard to detect, is most acute in fighters that make turns while going at incredible speeds.

“An hour is not an hour” to an aircraft constantly under the strain of G-forces, Gen. John D.W. Corley, head of Air Combat Command at Langley Air Force Base, Va., said at a news conference last month. “It’s like dog years.”

The more an aircraft is flown, the more expensive and more extensive maintenance becomes, Corley and Gen. T. Michael Moseley, the Air Force chief of staff, told the House Appropriations defense subcommittee during a Feb. 6 hearing.

The bottom line, the generals said, is older aircraft are in the shop more often and cost more to fly when they are available.