GAO Says B-2 Bomber’s Radar May Have Defect

WASHINGTON — The B-2 Stealth bomber’s sophisticated radar system may have a glitch when attempting to fly through rain and follow terrain at low altitudes, a draft report by the General Accounting Office has disclosed.

The GAO report sent to Congress asserts that the bomber is troubled by several new problems in addition to the balky radar, but Air Force officials characterized all the issues as relatively minor and low-risk.

The critical report could not have landed at Capitol Hill at a more politically inopportune time. Lawmakers are considering whether to buy 20 additional bombers for about $15 billion that would keep production lines going when Northrop Grumman completes the first batch of 20 bombers in 1998.

Northrop spokesman Tony Cantafio declined to comment on the draft GAO report, but mused, “What a coincidence that a draft GAO is released just as Congress is in the middle of considering B-2 appropriations.”

The political battle over the B-2 is considered one of the most important defense issues this year, a key test of whether Congress will move strongly to support the defense industrial base and continue to equip the military with the best technology. About 10,000 jobs in Southern California are at stake.

The draft report is the GAO’s first salvo against the B-2 this year, though GAO officials have insisted privately that they are not convinced the B-2 is as trouble-free as the Air Force and the plane’s supporters in Congress claim.

Although Northrop has delivered seven B-2s so far, they fall far short of having all the capability that the plane ultimately is supposed to have. The Air Force plan is to upgrade the B-2s through three successive phases, the last of which will not be completed until after this decade.

As a result, GAO officials have long asserted that the advertised ability of the B-2 to escape detection by enemy radar and operate behind enemy lines with impunity is far from proven.

Nonetheless, B-2 supporters have said the program is among the most trouble-free aircraft developments in history and that the plane has an extraordinarily good safety record with no crashes so far.

Among the most sophisticated parts of the B-2 bomber is its radar system, built at Hughes Aircraft in El Segundo. The radar system weighs more than a small car and is supposed to be capable of creating radar images of targets more than 50 miles away.

One of the radar’s functions is to allow the B-2 to fly at extremely low altitudes, allowing it to slip under enemy radar signals--a capability known as terrain following/terrain avoidance.

But the GAO report alleges that tests at Edwards Air Force Base in the Mojave Desert have found that the radar is “obscured” by rain.

Air Force spokesman Lt. Col. Jack Ivy said Friday that the B-2 schedule does not require the terrain avoidance capability to be ready for another two years, giving the service plenty of time to address the issue.

“While this does pose a risk, there is plenty of time to address it,” Ivy said.

In addition to the radar issue, the GAO report said B-2 deliveries have been delayed because of problems in making the planes as stealthy as required under Air Force specifications.

Ivy said it is true that some aircraft deliveries have been delayed because Northrop had to fix relatively minor workmanship defects that affected the plane’s ability to evade enemy radar. But he added that all seven existing B-2s at Whiteman Air Force Base in Missouri meet Air Force specifications for stealthiness.

The final issue identified by the GAO report involves problems with special coatings applied to the leading edges of the B-2 wings. The coatings are supposed to prevent the wing edges from being damaged when flying through rain.

After one plane at Whiteman was damaged during light rain, the Air Force discovered that Northrop had applied the coating too thinly and had used sandpaper with the wrong grit.