Defense Secretary Robert M. Gates on Tuesday laid out details of his plans to save $100 billion in five years as he tries to run the Pentagon more efficiently.

Pentagon spending has doubled, when measured in current dollars, in the past decade but its budget is expected to grow only slightly each year over the next decade.

Gates announced new guidelines, which signal a shift in how the Pentagon buys goods and services with the goal of continuing to save costs. The guidelines push for more "fixed price incentive fee" contracts, which typically require a supplier to take the hit for cost overruns but also reward the contractor for meeting a project's cost targets. Under the new guidelines, stricter rules won't allow expensive weapons projects to go forward if they don't stay within projected costs.

Money saved by cutting overhead and inefficient costs on weapons programs will go toward modernizing and recapitalizing military equipment and sustaining troops, officials said.

Gates on Tuesday said the Pentagon must get "more bang for the buck by shifting resources from overhead to the military capabilities needed today and in the future."

"Consumers are accustomed to getting more for their money - a more powerful computer, wider functionality in mobile phones - every year," Gates said. "When it comes to the defense sector, however, the taxpayers had to spend significantly more in order to get more. We need to reverse this trend."

The push to rein in the Pentagon's roughly $700 billion-a-year in spending began last year when Gates trimmed several big-ticket military hardware programs. Last month, he ordered the closing of the Joint Forces Command in Norfolk. And he took aim at reducing spending on "support contractors" by 10 percent each of the next three years, which could hurt local defense companies that provide professional, administrative and computer services. Also, for several months now about 40 top acquisition officials have looked for ways to eliminate inefficiencies and unnecessary overhead, according to Carter.

The savings plan Gates detailed Tuesday includes a five-step road map on how the Pentagon can be more efficient when it buys roughly $400 billion worth of goods and services including advanced aircraft, ammunition and submarines and contracts for feeding U.S. troops overseas, mowing lawns at military bases and running complex computer networks.

As part of the plan, the Pentagon will decide what it can afford to pay for a weapons system within its budget. Analysts say that often contractors bid on weapons and then return with ideas that can lead to runaway cost increases. The plan also includes incentives for contractors to keep costs low, better manage contracts, and reduce unnecessary, bureaucratic reports.

"In too many instances, cost estimates that are based on past programs - I might say past mismanagement - have deprived us of incentives to bring down costs," Gates said.

Defense industry analysts say it is unclear whether the savings plans will stick once Gates leaves. He has said will retire next year. Also, his goals could face congressional opposition. But others say it is possible that Gates's initiatives will remain intact.

"Gates has shown that he knows how to be forceful and even force Congress to do what he wants," said Winslow Wheeler, a defense industry expert. "It is clear to me that if he wants to make it happen, he can make it happen."