Pentagon budget: still as sacred 2nd time around?

From the lofty vantage point of a B-52, the Pentagon continues to win its major budget battles with those who would curb defense spending.

But down in the legislative trenches, where the elbows are sharp and the maneuvering can be tricky, another picture emerges.

The armed services still face determined budget cutters on Capitol Hill before they can declare themselves home free for the coming fiscal year. There are two new watchdogs over military waste and fraud who will reside outside the Pentagon. And within the Defense Department, civilian overseers in the Reagan administration are making slow but steady progress in demanding a more efficient and economical military.

Before adjourning, Congress passed a defense authorization bill giving President Reagan just about everything he asked for in ''big ticket'' weapons for 1983. Budgeting is a two-stage process, however, and the Pentagon can't actually spend its authorized sums until Congress appropriates them.

This means that House and Senate Appropriations Committees (which are generally less amenable to the Pentagon than the more friendly armed services committees that do the authorizing) still must have their say. And here, there are indications that deeper cuts will be made.

''Appropriations committees are much more penurious when it comes to putting up the bucks,'' observes a congressional source.

Under the congressional budget resolution passed earlier this year, House and Senate Appropriations Committees have directed their defense subcommittees to reduce the administration's 1983 military budget of $250 billion by nearly $12 billion.

The chairman of the House defense appropriations subcommittee is Rep. Joseph Addabbo (D) of New York, whose personal goal is to cut military budget authority by $20 billion to $25 billion. He opposes the B-1B bomber, MX missile, and two new nuclear aircraft carriers sought by the administration.

In the Senate, the chairman of the appropriations committee is Mark Hatfield (R) of Oregon, who also thinks the Pentagon can get along with less money. Other Republicans are pushing for defense cuts as well.

''Everyone in my state believes we're spending too much on defense,'' says Sen. David Durenberger (R) of Minnesota, who is running for reelection. ''Clearly the President and perhaps others just haven't gotten the basic message , which is that you can't measure the strength of your defense in dollars.''

Meanwhile, Congress already has ordered the Pentagon to be more accountable on weapons procurement so that cost overruns can be spotted sooner and perhaps headed off.

As part of the defense authorization bill, House and Senate agreed to strengthen and make permanent a requirement that the Defense Department report and explain any cost increase above 15 percent. Congress also tightened an earlier rule that made it possible for the Pentagon to get around certain reporting requirements by declaring that certain weapons weren't ''major,'' even though their cost went into the billions.

Congress also recently created a new civilian inspector general's post to detect and root out waste and fraud at the Pentagon. Until now, the Defense Department was one of the few federal departments (Treasury and Justice are the others) without an independent overseer. Defense Secretary Caspar W. Weinberger will have some say over any investigations that could jeopardize national security. But he will have to justify to Congress any control he exercises.

Recently, the Justice Department established a special unit to investigate and prosecute fraud in spending for military equipment and services. It is expected to become operational this fall, and has Mr. Weinberger's full support.

''We are very much aware that if the Defense Department is not perceived as clean as a hound's tooth, the consensus for a continued defense buildup may be endangered,'' says Pentagon spokesman Henry Catto.

Within the Pentagon itself, efforts are being made to operate more efficiently. Weinberger announced last week that in a recent six-month period, internal audit investigations yielded $2.3 billion in savings and potential cost avoidance. Those audits, in which corrective action is in progress, he reported, could bring another $3.2 billion in benefits.