TIM FURNISS / LONDON
Plans made to eliminate foam in the bipod area and install heaters to counter ice build-up
Five potential redesigns of the bi-pod area of the Space Shuttle external tank - where struts are attached to the nose of the orbiter - have been identified. The most likely solution will be to eliminate insulation foam in the bipod area and install heaters to prevent ice build-up.
The Columbia Accident Investigation Board (CAIB) is expected to demand a redesign of this area before the Shuttle returns to flight. NASA hopes to resume operations in the first quarter of 2004.
It is believed that foam insulation shed from the bi-pod area at T+81s during the launch of STS 107 Columbia on 16 January damaged the orbiter's left wing, starting the chain of events which led to the loss of the vehicle and all seven crew during re-entry on 1 February.
The Florida Today newspaper has reported that NASA has been flying Shuttles with twice as many accepted flaws than at the time of the 1986 Challenger disaster. The paper says NASA launched STS 107 Columbia with over 1,600 known problems that "could have destroyed the spaceship and killed its crew".
The CAIB is expected to cite "excessive waivers" among factors that contributed to the loss of Columbia and its crew. However, "in virtually every situation a waiver is a carefully thought-out process by which you decide that something is an acceptable risk", says Richard Bloomberg, former chairman of NASA's Aerospace Advisory Panel.
At least 5,800 waivers were recorded when Columbia was launched on 16 January, including 1,672 potential problems that could have resulted in the loss of the orbiter.
The Space Shuttle could return to flight in six to nine months and the "next couple of dozen missions will be the safest in years", says CAIB chairman Harold Gehman.
But he adds: "To fly the Shuttle long-term for 20 years more, there needs to be work on basic management changes." NASA has been guilty of "bureaucratic fumbling and administrative missed signals", says Gehman, who is calling for "urgency" on the development of a new-generation replacement for the Shuttle.
It is expected the CAIB will conclude that the loss of Columbia and its crew was the result of damage to the reinforced carbon-carbon heatshield panel No 8 on the left wing, which allowed hot gases to invade the internal structure of the wing. The board is likely to find that although NASA cannot eliminate the problem of insulation shedding, it must eliminate the loss of large chunks. The orbiter's wings must be strengthened and crews trained and equipped to repair the heatshield in orbit.
Source: Flight International
