Flight Rules Overruled

So it was, with this 'half-full-or-half-empty?' question hanging over the mission, that Wetherbee led his crew to Pad 39B early on 22 October 1992. Launch was originally planned for a week earlier, but had slipped because of problems with Columbia's Number 3 main engine; concerns arose over possible cracks in its liquid hydrogen coolant manifold. It was decided that it would be less time-consuming to simply replace the entire engine, rather than conduct a painstaking X-ray analysis of the damaged area. The engine was pulled out on 29 September and a replacement had been installed and tested by 2 October.

The mission would mark Wetherbee's second trip into space; his previous flight, STS-32 in January 1990, set a record of almost 11 days. Yet he was still at the start of a glorious career that would see him fly six missions in total, including two flights to the Russian Mir space station and another two to the International Space Station. In doing so, he also became the first - and, so far, only - American astronaut to command five space missions.

Not until the end of 2002, only weeks before Columbia's fiery loss during re-entry, would he hang up his helmet for the last time. His Pilot on STS-52, Mike Baker, was also making his second spaceflight, having occupied the same position on a nine-day mission the previous summer, which had deployed an important communications satellite for NASA. Mission Specialists were Lacy Veach, Bill Shepherd - later to become the International Space Station's first skipper - and Tammy Jernigan. All three had flown before: Shepherd twice, Veach and Jernigan once each.

The only member of Wetherbee's crew who would be savouring his first experience of flying into space on this mission was a Canadian physicist named Steve MacLean. He had been selected as a Payload Specialist only about eight months before Columbia was due to liftoff, and the bulk of his time on the planned 10-day mission would involve operating a battery of experiments provided by his own country, including an important space-vision system which was being evaluated for use during the construction of the International Space Station.

Even though their launch had been delayed by a week, when the crew finally set off at 5:09:39 pm on 22 October, they still set a new post-Challenger record for the shortest interval between two flights by the same Shuttle. Columbia had returned to Earth from her previous mission, STS-50, only 105 days earlier. Nevertheless, launch on the 22nd was delayed by almost two hours due to unacceptable crosswinds at the SLF runway, which would have been used if problems during the early part of Columbia's ascent had forced Wetherbee and Baker to perform an emergency landing in Florida.

However, after discussions between members of the Mission Management Team, chaired by former astronaut Brewster Shaw, it was decided that although the 37-km/h SLF crosswinds exceeded flight rules (which stipulated speeds no higher than 27 km/h), they were 'safe' enough for Columbia to go. Ascent Flight Director Jeff Bantle's reservations were overruled and Shaw decided, based on simulations that showed that Wetherbee and Baker could brake the Shuttle safely to a halt if necessary in the faster-than-desired winds, to proceed with the launch attempt.

''We accepted Jeff's recommendation,'' Shaw said later at a post-launch press conference, ''based on his interpretation of the guidelines, and made a management decision that went in a different direction.'' Fortunately, an abort landing was not necessary and Columbia followed a picture-perfect ascent trajectory, inserting herself into a 302 x 296 km orbit after a single OMS burn. The veteran flagship's 13th mission, which, by chance, would also be aloft over Hallowe'en, was underway as the crew doffed their pressure suits and got ready for 10 days of intensive activity.

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