The Air Force, after an unexpected fight on Capitol Hill, has won the right to begin issuing leather flight jackets to air crews.

The service plans to award a contract momentarily for brown leather flight jackets, joining the Navy in providing aviators a special uniform article "to enhance esprit de corps," said Capt. Chris Canfield, a spokesman.

The first jackets probably will not arrive in the field for four to five months, Canfield said, but ultimately about 43,000 pilots, navigators and enlisted air crew members will receive the jackets.

Gen. Larry D. Welch, the chief of staff, authorized the return of the brown leather flight jacket after an almost 40-year absence last June.

But when the House and Senate appropriations committees began reviewing the fiscal 1988 budget, the panels balked at the expense and questioned whether issuing leather jackets would do much to shore up sagging pilot reenlistment rates.

The jackets are not cheap -- more than $100 -- and the Air Force expects to spend roughly $7.4 million buying an initial stock of 53,000.

Despite the committee rulings, Air Force brass did not want to give up the idea. And by the time the fiscal 1988 spending bill emerged from Congress last week, the prohibition on spending money for jackets had been removed by House and Senate conferees.

In persuading key legislators the jackets were needed, the Air Force stressed it was merely trying to recognize the job that front-line air crew members perform.

"It really is a recognition item," Canfield said. "The message is that we care about our front-line crew members and want to recognize them for the job they do. If by enhancing esprit de corps that has any effect on reenlistment, then that's just icing on the cake."

Both the Navy and Air Force have suffered from falling reenlistment rates among pilots for several years, thanks largely to efforts by commercial airlines to expand operations. The problem is a costly one for both services, since it takes $1 million just to provide basic training and much more to produce a seasoned pilot.

The Navy authorized a return of the leather flight jacket for its aviators in 1983 after a six-year hiatus, but they have been missing from the Air Force since shortly after World War II.