Launch problems spread to DOD.

Launch problems spread to DOD 

Even before the Jan. 28 explosion of the space shuttle Challenger, the Department of Defense (DOD) had been well along in planning a return to increased use of one-shot, "expendable" rockets for some of its launchings. Besides the limited size of the shuttle fleet, the craft's complexity raised concerns about its reliability among military planners, who cited a need to keep tried-and-true expendables around.

On April 18, however, DOD found itself in a launch-vehicle turmoil of its own, when one of its most reliable rockets--a Titan 34D, which is also the most powerful workhorse in the U.S. military stable -- blew up only seconds after lifting off from Vandenberg Air Force Base in California. To make matters worse, this was the second failure of an Air Force Titan 34D. The other occurred last Aug. 28.

Both payloads were classified, but various nongovernment specialists speculated that in both cases it was a KH-11 reconnaissance satellite, a half-billion-dollar spy-in-the-sky of a type used to take high-resolution photos of the Soviet Union and other areas. Only one KH-11 is now believed to be operating in orbit, with but a single replacement in reserve on the ground.

The Air Force has launched 136 rockets (plus five earlier test flights) in the various versions that make up its Titan 3 series. Of these, nine have been 34Ds, most powerful of their kind. There have been only six failures among the 136, but they include the last two 34Ds. There are just six more 34Ds in stock, and the still more powerful version yet to come, called the 34D7, is not due to go into use until 1988.

All six 34Ds have payloads tentatively assigned to them, as do the ten 34D7s being built. But now the Air Force is confronted with uncertainties not only in the space shuttle but in its own expendables as well. "Priorities," says an Air Force spokesperson at Vandenberg, "could change." NASA, for example, has been attempting to work out a possible launch schedule for when the shuttle finally begins flying again, and several of the payloads were already going to be military. But if the 34D is also going to be delayed for a significant period (an investigation of last week's explosion is under way), NASA's post-Challenger planning efforts could well be overturned again.

Meanwhile, NASA's first post-Challenger launching is tentatively set for May 1. Its payload, the NOAA-G weather satellite, will be lofted by an expendable Scout rocket.