Struggling to pay for a costly war in Iraq, the Pentagon (search) is considering as much as $15 billion in cuts to aircraft, shipbuilding and other weapons purchases as it begins to craft a budget for next year.

Defense analysts and congressional staff say such reductions could hamper efforts to replace equipment worn out in the Iraq and Afghanistan wars and outdated Cold War-era weapons systems. Any proposed cuts are likely to set up a fierce battle, as members of Congress — including majority Republicans — strive to protect programs that pour millions of dollars and thousands of jobs into their local economies.

Sen. John Cornyn (search), R-Texas., said cutting critical programs like the F/A-22 Raptor fighter or the Joint Strike Fighter, a next-generation aircraft, could face resistance.

"Such shortsighted cuts may yield greater budget flexibility now, but will hamper our national security potential far into the future," Cornyn said of possible cuts to funding for both warplanes, which are partly built in Texas.

Defense Secretary Donald H. Rumsfeld (search) on Tuesday said the department has to move funds around to ensure that the country gets what it needs to fight both conventional conflicts and unconventional threats, such as the insurgency in Iraq.

Compounding the pressures are the government's record budget deficits. The federal government ended fiscal 2005 on Sept. 30 with a shortfall of $319 billion, the third largest ever.

While Rumsfeld and other military officials declined to talk about specific spending decisions, defense analyst Loren Thompson said Gordon England, the acting deputy defense secretary, is looking to trim $12 billion to $15 billion from previous plans to spend $443 billion in 2007. Defense contractors have cited similar figures.

The Army, Navy and Air Force would be responsible for cutting as much as $3 billion to $5 billion each, Thompson said.

"The war in Iraq, Hurricane Katrina and domestic needs are all combining to put downward pressure on weapons spending," said Loren Thompson, an analyst with the Lexington Institute. "At the very least, this means a difficult budget year, with lots of disagreements between Congress and the administration."

Overall, the cuts would slice about 3 percent from each of the services' 2007 budgets that were envisioned last year.

Among the programs being considered for significant cuts or delays are the Joint Strike Fighter, the Pentagon's next generation, all-purpose fighter, which is built in Texas; the C-17 transport plane, which is built in California; the Navy's new and expensive DD(X) destroyer, being built by Northrop Grumman Ship Systems; and a reconnaissance aircraft called the Aerial Common Sensor, which is being developed by a team led by Lockheed Martin and has had a number of problems.

Military contractors are bracing for the cuts, or even decisions to eliminate entire programs. Lockheed Martin's chief financial officer Chris Kubasik recently conceded to analysts that the future of its reconnaissance aircraft was in question, saying, "it is premature to predict an outcome at this time."

A Pentagon spokeswoman, Marine Lt. Col. Rose-Ann Lynch, said no decisions have been made on the fiscal year 2007 budget, which will be unveiled next February. But she said all the military services and Pentagon departments have been asked to think about possible changes, and "all options are on the table."

Under the current defense budget, weapons purchases — for everything from fighter jets and destroyers to communication systems — would increase from about $78 billion in 2006 to $91.6 billion in 2007. Pentagon officials are looking to shave as much as $15 billion from the planned $91.6 billion, triggering what would be a rare reduction in procurement levels.

"This year it looks like the defense budget is cresting downward," said Richard Aboulafia, a defense analyst with the Teal Group, a defense consulting firm. "The defense budget is flattening. We haven't recapitalized a lot of equipment. Worse still, most of the military inventory is being worn out at five times the normal rate."

The result, said Sen. Jack Reed (search), D-R.I., is a classic dilemma.

"Are we going to continue to pour billions into Iraq, or are we also going to prepare for future conflicts, hopefully to deter them, by having the most sophisticated equipment?" Reed asked.

Different versions of the Joint Strike Fighter are being developed for the Air Force, the Navy and the Marines, and there have been discussions that one of the models could be eliminated. The Pentagon also could delay the development of the next generation aircraft carrier — the CVN 21 — which is scheduled to begin construction in 2007.

The ongoing spending discussions coincide with the Defense Department's quadrennial defense review, a broad-based look at what the military will need — in people, equipment and structure — to fight 21st century wars. The review is expected to recommend what types of ships, aircraft and other systems should be bought.