NASA Officials Deny Firm Was Pressured to Launch

National Aeronautics and Space Administration officials testified Wednesday that an initial recommendation by the builder of the space shuttle Challenger’s booster rockets to postpone liftoff of the craft was flawed by data that “didn’t hang together.”

In their first full account of a crucial debate the day before the ill-fated launching of the Challenger, NASA officials conceded that they argued against the position that cold weather could endanger the flight. But they contested earlier testimony that their stance pressured executives of Morton Thiokol Inc., the booster rockets’ manufacturer, to reverse the recommendation of company engineers to postpone the Jan. 28 flight.

George Hardy, deputy director of science and engineering at NASA’s Marshall Space Flight Center, told a presidential commission investigating the Challenger disaster that “since the issue was first raised, I have racked my brain to try to see if there was any conceivable motivation that may have had any contractor representative feel that he was under pressure from anything I said.”

Hardy said he could recall none. Similarly, he and other NASA witnesses testifying in the second of three days of public hearings disputed testimony taken on Tuesday from Morton Thiokol engineers that the space agency forced the company into the unprecedented position of having to prove that a launching would not be safe.

“I categorically reject any suggestion that the process was, ‘Prove to me it isn’t ready to fly,’ as opposed to the traditional approach of, ‘Prove that this craft is ready to fly,’ ” Hardy said. But he admitted he had told Morton Thiokol engineers he was “appalled” after they recommended against launching.

The NASA denials were greeted with obvious skepticism by several members of the presidential commission impaneled to investigate the nation’s worst space disaster and make recommendations about reforms.

Commission members repeatedly expressed bafflement about NASA’s refusal to accept on face value the original analysis by Morton Thiokol that sub-freezing temperatures forecast for launching threatened to undermine the performance of vital seals, or O-rings, between joints in the multisectional booster rockets.

At the end of the daylong session, the commission began to hear testimony from two members of a launching pad “ice team” who described extremely icy conditions on the morning of launching and said they had recorded temperatures as low as 9 degrees on the lower right-hand part of the rocket, the one suspected of failing. Their testimony was to be resumed today.

18-Month Delay Seen

In a related development, the acting head of NASA, William R. Graham, told a congressional subcommittee that it could be 18 months before NASA can launch any of its three remaining shuttles. He said the space agency was weighing the possibility of using unmanned rockets in the meantime as a way to meet its commitments to satellite companies.

On the day before the Challenger’s launching, Morton Thiokol engineers had been unanimously opposed to sending the spacecraft aloft. But, after hearing NASA experts challenge their admittedly imprecise data, company executives withdrew that recommendation and delivered to NASA a written consent to launch.

Failure of the O-rings envisioned by the engineers--now a leading suspect in the effort to determine the cause of the Challenger explosion--has for three years been recognized as a portent of a fireball that would consume spacecraft and crew.

Commission members bore down hard on the question of why the NASA propulsion experts did not pass along the preliminary concerns of Morton Thiokol to the space agency hierarchy responsible for the final decision to launch.

‘Going by the Book’

Commission Chairman William P. Rogers prefaced a question to Stan Reinartz, shuttle project manager at the Marshall Space Flight Center, where NASA propulsion activities are headquartered, by saying he was aware of the phrase, “going by the book.”

“But doesn’t the process require some judgment?” Rogers asked. “Don’t you have to use common sense? Wouldn’t common sense require that you tell decision-makers about this serious problem?”

Reinartz and other NASA witnesses testified that they were convinced the Morton Thiokol concerns had been dispensed with properly during the lengthy telephone conference on the eve of launching and that it was not necessary to inform top officials about the discussion.

They said also that they were unaware that Morton Thiokol engineers at the company’s Utah facilities had, in a private caucus, bitterly opposed the final company position that the launching was safe.

Air Force Maj. Gen. Donald J. Kutyna, a commission member and former manager of the Defense Department’s space shuttle program, compared the critical importance of the O-rings to the wing of an airplane. “If this was an airplane and I had just had a two-hour argument with Boeing about whether a wing was going to fall off,” he said, “I’d want to tell the pilot about it.”

Vocal Disapproval

The commissioner most vocal in expressing his disapproval of NASA’s handling of Morton Thiokol’s initial objection to the launching was Joseph F. Sutter, executive vice president of the Boeing Commercial Airplane Co. Sutter has been described as “the Father of the 747” for his close involvement with the development of that jumbo jet.

Sutter noted that booster seals, and O-rings in particular, have been the subject of intensifying study at NASA and Morton Thiokol because of evidence that on numerous occasions the seals were partly eroded or charred in flight. He questioned why NASA continued to fly before a permanent solution was found.

When NASA solid rocket projects manager Lawrence B. Mulloy testified about joint erosion suffered on the fourth shuttle flight, Sutter commented acidly, “It’s lucky it got home, I guess.”

Sutter recalled that Morton Thiokol engineers Tuesday introduced internal memorandums written last July suggesting that the O-ring problem jeopardized flight safety and was not receiving proper attention. One of the engineers called for a halt to all shuttle flights until the seal problems could be fixed.

“It just seems to me,” Sutter said at another point, “that the whole system was not aware of how serious this was . . . . It seems to me the philosophy was, ‘Let’s keep ‘em flying while we work on the changes.’ ”

He criticized Mulloy for having criticized engineers for in effect proposing new launching criteria during the prelaunching discussion. The Thiokol engineers said at that time that the flight should not be attempted with O-ring temperatures below 53 degrees.

“There were three levels of improvements that were discussed,” Sutter said. “The thing to do was to put those improvements into the program--not to infer that these engineers were throwing a ringer at you of ‘Don’t launch until next April.’ I think that putting those engineers in a little bit of a hot seat--they were just trying to do their job and say, ‘Hey we ought to do something about this.’

“There ought to have been more attention paid.”

Rationale ‘Illogical’

Mulloy testified that he found the rationale presented by Morton Thiokol engineers at the prelaunching conference “illogical.”

He said the data did not prove there was a correlation between O-ring damage and cold weather. Among other faults with the data, Mulloy said, is that it failed to take into account the known dynamics of how the primary O-ring and its back-up O-ring function during the first fractions of a second when the rockets are lit.

“It didn’t hang together,” Mulloy testified. “It didn’t hang together with all our other experience and our knowledge.”

Mulloy and other NASA officials testified that there was nothing unusual with their aggressively challenging data presented by a contractor. They conceded, however, that they had no experience with a Morton Thiokol recommendation against launching, a novel development that commissioner Sally K. Ride, an astronaut, suggested might have produced a role reversal that led to misinterpretations of NASA statements by Morton Thiokol.

Commissioners also pressed NASA officials about Morton Thiokol’s final written recommendation in support of launching, particularly its statement that back-up O-rings would work if primary O-rings failed to stop the dangerous flow of hot gases from the rocket.

NASA had upgraded the primary O-rings to a so-called Critical One item--meaning failure would bring certain destruction of spacecraft and crew--because it had been discovered that forces of liftoff could dislodge the secondary O-rings after the rocket ignited, making them useless.