Air Force Secretary Donald B. Rice, addressing apparent shortcomings in the B-2 Stealth bomber, said he believed that after further work the aircraft would be about 80% as successful in evading enemy radar as the military originally had hoped.
"I'd put it up around an 8 (on a scale of 1 to 10) . . . in terms of how much of what we're trying to achieve" that we're going to get, Rice told reporters at the Pentagon.
Rice's admission that the Stealth bomber's ability to evade enemy radar might fall well short of Air Force projections could deal a serious blow to the embattled plane, which is to be built in Palmdale and Pico Rivera by Northrop Corp.
The Air Force secretary's comments came two days after lawmakers learned that the $860-million-per-copy plane had failed a key test of its stealthiness during a test on July 26.
Citing security, Rice and other Pentagon officials have refused to elaborate on the nature of the test or say how far short of the goal the plane fell.
On Friday, Nebraska Democrat James Exon, a key B-2 supporter in the Senate, warned that the Stealth program will die "a fast natural death" in Congress unless the problems with the radar-evading features are quickly resolved.
Exon, who appeared exasperated at conflicting accounts of the B-2's shortcomings from different Pentagon officials, said the "Air Force's credibility is now at a new, all-time low in the halls of Congress."
The White House, meanwhile, on Friday continued to back the plane despite the testing woes.
"We have confidence in the military's ability to work with the contractors to make this as good a project as we can get, and we continue to support it," White House spokesman Marlin Fitzwater said.
Rice called the test failure "a problem," but added, "I would not characterize it as a major problem."
Coming on the eve of sensitive House and Senate negotiations over the future of the plane, news of the problem is expected to damage the bomber program's political and budgetary prospects. Indeed, Exon announced Friday that he had canceled a meeting with House counterparts next week, at which he had planned to defend the bomber program.
Exon, chairman of the Senate Armed Services Committee's nuclear forces subcommittee, said he and Sen. Sam Nunn (D-Ga.), chairman of the Senate defense panel, were summoning Air Force chiefs next week for a private briefing. He warned that the future of the plane depended on their answers.
The Senate has approved limited production of the plane. But in its version of the $292-billion defense authorization bill for next year, the House voted to stop production after the 15 planes ordered so far have been built.
Negotiations to reconcile the Senate and House bills, which must be complete before Congress takes final action, begin next week.
Rice said Friday that making repairs to bring the bomber's radar-evading ability beyond the 80% level might not be worth the cost and effort, especially given expected changes in the Soviet Union's future military prowess. At the same time, Rice said the Air Force is not dropping its original objective for the bomber's stealthiness.
"We still want to work against, need to work against, the operational requirements that have been laid down," Rice said.
Officials have cautioned that, even if 100% of the Air Force's objectives for the plane were met, the Stealth bomber would not be wholly invisible to air defense radars as it attempts to penetrate an adversary's airspace.
Rather, the plane's appearance on air defense radars would be minimized, say, to the size of a bird, by a combination of the bomber's airframe design, deceptive electronic devices and special coatings.
By suggesting that the Air Force may not be able to meet its original goals for the B-2's Stealth characteristics, Rice conceded that the plane could be easier to detect if it is used in areas defended by dense and sophisticated air defense radars.
But critics of the Stealth bomber have complained that, with the end of the Cold War and the political and economic turmoil in the Soviet Union, the United States no longer needs to field a bomber that can slip past sophisticated air defense radars. Indeed, many analysts contend that the Soviet Union will never be able to mount the air defenses against which the B-2 bomber was designed.
"Even though the B-2 is not very stealthy anymore, the Pentagon is going to argue that we can still use it, because we're down to countries that can't afford radar any more," said Rep. Barney Frank (D-Ma.).
Rice added that, under the terms of the Air Force contract, the plane's prime contractor, Northrop Corp., could suffer financially if the plane's shortcomings are not corrected in future tests.
"Northrop is responsible to deliver a (radar) signature level up to the contract specifications," Rice said.
He called the test failure an "event" rather than a "problem," and explained that the shortfall was declared when an expected improvement in the plane's stealthiness failed to materialize in a second round of flight tests.
"It involves an amount of improvement that is significant or we wouldn't be trying for it," Rice said.