TIM FURNISS / LONDON

Agency told of untested system's potential to cause a "Challenger-type" accident

NASA and the US Congress were warned in January last year that the bolts that connect the solid rocket boosters (SRB) to the external tank of the Space Shuttle and the "boltcatcher" system had the potential to cause a "Challenger-type" accident.

A new company - as yet unidentified - was contracted in 2000 to manufacture the bolt systems after the incumbent supplier, Hi-Shear, lost the contract.

Hi-Shear was concerned enough about the quality of the new company's work to notify NASA and Congress that the systems were "potentially faulty and guaranteed to cause disaster".

The Columbia Accident Investigation Board (CAIB) said on 12 June that the boltcatcher systems did not appear to have been properly tested nor were there adequate safety margins.

During the launch of the STS 107 Columbia mission - when external tank insulation foam was seen to hit the orbiter's wing, probably causing the damage that resulted in the craft's destruction during re-entry - a piece of debris was also seen on radar in the vicinity of the orbiter at SRB separation. This is thought to have possibly been part of the bolt system that had not been "caught" in the boltcatcher. The bolts are sheared as the booster separates.

Although the bolt system is not thought to have had a bearing on the Columbia accident, it is almost certain that the CAIB will recommend that the system be thoroughly tested before the Space Shuttle returns to flight.

Meanwhile, NASA's director of the Kennedy Space Center (KSC), the former Shuttle pilot US Air Force Gen Roy Bridges, appears to be the third high-ranking head to roll after the Columbia STS 107 accident, following Shuttle director Ron Dittemore and Marshall Space Flight Centre director, Art Stephenson.

Bridges has been moved to lead the NASA Langley Research Center and will be replaced by deputy director James Kennedy until a new KSC director is appointed.

Source: Flight International