A top NASA official told a House committee yesterday that, contrary to the earlier testimony of his deputy, he had not been informed in detail last August of engineers' serious concerns about the solid rocket boosters that caused the Jan. 28 space shuttle disaster.

The apparent conflict in testimony centered on an Aug. 19, 1985, briefing at National Aeronautics and Space Administration headquarters in which engineers from booster manufacturer Morton Thiokol and NASA's Marshall Space Flight Center in Houston briefed headquarters officials about serious problems with the booster O-ring seals. Failure of an O-ring six months later caused the disintegration of the shuttle Challenger and the deaths of its crew of seven.

Officials at the briefing concluded that it was "safe to fly," as long as the O-rings met certain specifications, and recommended an accelerated effort to fix the problems.

The Rogers Commission, in its report on the accident issued June 9, said the information presented in the briefing "was sufficiently detailed to require corrective action prior to the next flight."

Jesse Moore, who was then head of the shuttle program, missed the briefing. His technical deputy, Michael Weeks, attended.

On June 12, Weeks told the House Science and Technology Committee under oath that he had briefed Moore about the Aug. 19 meeting that same evening. "I briefed him on the results of that and told him about the briefing and showed him the briefing."

Yesterday, in response to questioning by Rep. James H. Scheuer (D-N.Y.), Moore said, "I did not get the report from Mr. Weeks. I did not read that report that was given to NASA headquarters on Aug. 19."

After Scheuer read Weeks' testimony to him, Moore, who is now director of the Johnson Space Center in Houston, said, "That certainly is not commensurate with my recollection of the situation. Mr. Weeks did say he attended the briefing, that he did review the situation with Morton Thiokol and Marshall people. He felt at that time that his judgment was that it was okay to proceed . . . . The first time I saw the briefing document was . . . after the Challenger accident."

Moore said he was aware of O-ring problems in the booster joints but did not have information that indicated the problems were serious enough to stop flying shuttles.

Scheuer called the testimony "a very serious conflict," and he told Moore, "You were the top banana. They say the buck stops here."

Moore responded, "I understand that. You have to rely on people in your organization to make judgments . . . and that's what I thought I was doing, sir."