Still Grounded

The contrast was stark. Soviet Cosmonaut Yuri V. Romanenko returned happily to earth last week after spending a record-setting 326 days in the space station Mir, a prototype of one from which the Soviets hope to send men to Mars before the end of the century. The same day, NASA announced that part of a newly designed booster rocket had failed during a test firing at a Morton Thiokol plant near Brigham City, Utah, causing an undetermined delay in the faltering effort to resume U.S. manned space missions. At the same plant, five workers were killed when nearly 100,000 lbs. of solid rocket propellant for an MX missile section accidentally ignited. Since a similar fueling procedure is used for the shuttle boosters, that problem must also be solved before the next U.S. manned space flight is launched.

The failure in the booster-rocket test was unrelated to the malfunction that caused the Challenger explosion on Jan. 28, 1986, when fire burned through an O-ring that sealed the joint between two rocket sections. This time the problem was in a flexible boot ring that helps anchor the swiveling rocket nozzle to the rigid booster case. Nearly half of the ring, which is 8 in. wide, 2 in. thick and 8 ft. in diameter, broke away during the horizontal ground test; some pieces were found inside the booster. The nozzle had been deliberately shifted 7 degrees, just 1 degrees short of its maximum movement.

The boot ring had been redesigned because an earlier type had eroded on several missions. Morton Thiokol officials said a different type of nozzle joint had been tested successfully in August and could be reinstalled. "We have a parallel design, and we also have some rings of a different configuration on the shelf," said John Thomas, a NASA engineer who began examining the failure. "What we have to do is understand exactly what happened so we can clear this ring or another one."

Morton Thiokol stopped its scheduled shipment of aft booster segments to Cape Canaveral, Fla., where an astronaut crew had hoped to resume flights on June 2. NASA estimated that the longest probable delay from the nozzle failure would be three months. But some of the agency's veterans speculated that the Administration will not want to risk a launch until after the November elections.

The MX fire was seen as more of an avoidable accident than a fundamental problem with the long-range nuclear missile or with standard fueling procedures, which had been performed safely thousands of times. Actually, the MX has had far more serious problems with its faulty guidance system. The propellant ignited as workers were removing a device used in the fueling process. Flames shot 50 ft. into the air, and the remote building was reduced to twisted pieces of metal. The five workers in the building had no chance to flee the inferno.

The twin failures at Morton Thiokol raised new congressional complaints about the troubled contractor. The comparative Soviet success in manned space flight worried other experts. Declared John Pike of the Federation of American Scientists: "The Soviet cosmonauts got a big boost on their way to Mars. They know where they're going. We don't."