Space Shuttle Mission 51-L: The Search For Clues
Film Implicates Solid-Fuel Booster
Sunday, February 2, 1986
NASA yesterday released new film footage showing that one of the space shuttle Challenger's solid-fuel boosters was defective and had begun spewing "an unusual plume," which appeared to be a flame, about 14 seconds before the explosion that destroyed the shuttle.
The film, the first significant break in the investigation of Tuesday's disaster that killed seven crew members, revealed that as of 59.82 seconds after liftoff, the booster on Challenger's right side had ruptured about one-third of the way up from its base and was emitting a plume of hot gases that appeared to grow larger until the explosion.
The film -- enhanced by computer and transferred to videotape -- was made by a 70mm camera located north of the launch pad that had a different view of the shuttle from that of the cameras that supplied the previously broadcast images.
Those cameras, situated south of the pad, could not see the right-hand booster and showed nothing amiss until about one second before the blast.
The solid rocket boosters, now even more critical as evidence in the investigation of the crash, were blown up on radio command from earth about 30 seconds after the explosion because of fears they might veer into an inhabited area.
NASA spokesman Hugh Harris declined to speculate on the significance of the plume, even refraining from calling it a flame. Harris said NASA's interim investigating board had not reached any conclusion as to whether the plume was a cause or an effect of the problems that befell Challenger. Harris said the National Aeronautics and Space Administration "cautions against drawing any conclusions from the pictures."
If the plume is confirmed after further investigation to be a jet of hot gases leaking from the solid rocket, it could have caused the explosion by heating the adjacent tank of liquid hydrogen fuel, almost like a blowtorch, and melting a hole that released the highly explosive hydrogen.
The film, as well as new still photographs also released last night, were the first bits of solid information given out by NASA since the space agency's massive investigation got under way Tuesday after the accident. They were released about 8:50 p.m. at a NASA briefing at the Kennedy Space Center in Florida. NASA officials declined to interpret or comment further on the film or its meaning. They said they released the materials because they were something new that could be shared with the public.
Earlier in the day acting NASA Administrator William R. Graham briefed members of Congress, showing them what was believed to be a different film that revealed the same plume.
The announcement followed a day of confusion in which NASA officials denied a variety of news reports that new clues had been found to implicate the solid rocket boosters.
In the immediate aftermath of the disaster, many aerospace scientists said they doubted the boosters were at fault because they continued flying out of the fireball.
The boosters were flying so well that Air Force technicians blew them up out of fear they would curve back toward populated areas. That act, it is now evident, may have destroyed physical evidence of what went wrong.