Several high-ranking military retirees working as civilians with the National Aeronautics and Space Administration now draw combined pay and retirement that is more than a member of Congress earns.

They are among several hundred ex-military officers who, by special legislation, are permitted to take second careers with Uncle Sam without losing any retirement benefits.

Congressional sources estimate that there are more than 40 retired generals and admirals -- earning as much as $77,200 a year in pay and pension --now in high government civilian jobs.

All in all, NASA has 17 military retirees in top administrative, policy or training jobs who are permitted to keep full military pension plus their civilian federal salaries. Civilian pay William R. Pogue, who are attached to the Space Shuttle program, to at least eight retired generals, admirals or other high-ranking retirees whose civilian salaries at NASA are $47,500. Pension income, which varies with individuals, is in addition to these salaries.

Under the dual compensation act, retired regular officers normally must give up all their military retirement when taking jobs with the federal government as civilians. Retired reserve officers, and all enlisted retirees, can keep the first $4,219 of their retirement pay, plus one half the remainder, while working at government jobs. Next month that figure goes up to $4,320 when the retirees, like other ex-civilian and military personnel, get a 2.4 per cent cost-of-living raise.

That waiver of military retirement pay, however, is permitted to NSA and several other agencies under a special act of Congress. It was designed to allow agencies to offer top dollar -- and full retirement benefits --to outstanding military retirees.

The waiver practice has irked some civilian workers, who fell a "buddy system" operates in government with retired military people hiring former associates, subordinates and commanders. It also irritates retired regular officers, West Pointers and Annapolis graduates, who feel they are discriminated against in government employment compared to colleagues who held reserve commissions.

The 1964 Congress that authorized the dial compensation act benefiting retired enlisted personnel and reserve officers taking government jobs had an estimated 175 members who held reserve commissions.

Most of the 141,000 retired military personnel working for the government came from the enlisted ranks or held reserve commissions entitling them to dual compensation.

In addition to the high-ranking (Grade 16 through 18) retired regulars who have been allowed to draw full military pensions and civilian pay, federal officials estimate there are many other regular officers/in lower-level government jobs who have been exempted from the dual compensation act. Many are doctors or are in scientific jobs with Army, Navy, Air Force, and in either medical or/professional jobs with Veterans Administration, Energy Department, and the Department of Transportation.

In all but a few cases, retired federal workers who are rehired by the government have their pay offset by the amount of the pension they are drawing.

Only a few former federal employes, most of them individuals retiring from Secret Service or law enforcement jobs who elect to go out under a more generous D.C. government pension system (that is not available to most federal or D.C. workers), generally are allowed to draw full civilian retirement and full civilian pay.

The Carter administration has informally talked about eliminating dual compensation, or of giving retired regular officers the same pay-pension break that now goes to reserve officers and enlisted personnel. But officials have put off any legislative proposals pending a report from a blueribbon panel that has been studying the entire military compensations system.

Backers of dual compensation argue that the unique makeup and career progression of the military make it unfair to compare federal civilian or private retirement plans with the military. Military personnel, for example, must serve at least 20 years in most cases to be eligible for any sort of pension. There is no severance pay, or partial pension for them if they leave --fore logging in the magic 20 years.

In testimony before Congress last July, Navy Vice Adm. Hyman Rickover argued for an overhaul of the various federal and military pensions systems. He was especially hard on high-ranking "doubledippers."

Rickover has asked for elimination of waivers from the dual compensation act. "These loopholes," he told a congressional subcommittee, "benefit only a small group of retired senior officers, generally those who happen to be in positions of influence prior to retirement. I find it difficult to believe that their services, past or present, warrant federal pay greater than a congressman's or senator's salary."