An array of military programs, from fighter jets to retiree benefits, would be nicked to squeeze savings in the Pentagon’s $525 billion budget for 2013, according to officials and documents released Monday.

The proposed 2013 budget represents the Pentagon’s first installment in a plan to reduce its projected spending by $487 billion over 10 years. Congress must approve the changes.

“They’re buying less of a lot of some systems, and delaying a lot of other systems,” said Todd Harrison, a military budget expert at the Center for Strategic and Budgetary Assessments, a non-partisan think tank. “A little here, a little there. It adds up.”

The Joint Strike Fighter, the future mainstay of the military’s air combat power, is an example of a program targeted for cuts. The Pentagon would purchase 29 of the planes in 2013 for the Air Force, Navy and Marine Corps, 13 fewer jets than planned. That would save $1.6 billion in 2013.

The Pentagon envisions more savings by cutting more than 100,000 servicemembers over the next five years, most from the Army and Marine Corps.

Benefits for military retirees are also targeted. The Pentagon is proposing substantial increases in health care premiums for working- age military retirees. For some retirees, the premiums for TRICARE, the military health-care program, would nearly quadruple from $520 per year to $2,480 in 2017.

Veterans’ advocates denounced the proposed increases. Retired vice admiral Norb Ryan, president of the Military Officers Association of America, called it a “a significant breach of faith with those who have already completed arduous careers of 20-30 or more years in uniform.”

The increased premiums would likely compel some retirees who hold jobs to buy insurance through their employers rather than the military, resulting in savings for the Pentagon, Harrison said.

A less likely source of immediate savings for the Pentagon, Harrison said, is a proposal to close military bases. The Pentagon plans to ask Congress for two rounds of base closures in 2013 and 2015.