Pushing The Envelope

Launch was originally planned for 18 December 1989, which - judging from its planned 10-day duration - would have made the STS-32 astronauts the first-ever Shuttle crew to spend Christmas in orbit. This evidently played so much on their minds that they privately arranged for an impromptu crew portrait to be taken, in which they dressed in Santa suits, hats and dark glasses. Fortunately, they also wore their NASA name-tags to make them identifiable. It was not to be the only prank that Brandenstein's team would play ...

Since the Shuttle's return to flight after the Challenger disaster, most missions had lasted around five days. STS-32 would push the envelope by getting close to - or even exceeding - the 10-day record set by John Young's STS-9 crew at the end of 1983; according to the pre-mission press kit, Brandenstein's mission was planned for 9 days and 21 hours. Although the deployment of Leasat and retrieval of the LDEF did not require the unusually long mission, an increasingly confident NASA wanted to demonstrate the Shuttle's capabilities as it was planning to modify Columbia for missions lasting up to a month.

The STS-32 crew with a model of the LDEF. Left to right are David Low, Marsha Ivins, Bonnie Dunbar, Jim Wetherbee and Dan Brandenstein.

The processing of STS-32 involved modifications to support the longer-than-normal mission: a fifth set of cryogenic oxygen and hydrogen tanks was installed under Columbia's payload bay floor. This enabled the fuel cells to produce electricity and, as a byproduct, drinking water for the crew. By the end of November 1989, the Shuttle stack had been rolled out to Pad 39A - becoming the first to use this pad since STS-61C - in anticipation of a launch a few days before Christmas. Unfortunately, problems getting Pad 39A ready resulted in a delay until 8 January 1990, so the Santa joke fell flat.

The next obstacle was weather. ''Our main concern'', said US Air Force meteorologist Ed Priselac on 6 January, just after the countdown started, ''is that low-level cloudiness will not clear out of here very quickly.'' This threat also included showers obscuring high-altitude cloudiness associated with a slow-moving cold front, which reduced the prospects of acceptable weather on the 8th to just 40%. The chances of successfully setting off that day were reduced still further by a comparatively short, 54-minute launch window, which had been precisely timed to allow Columbia to rendezvous with the LDEF early on the mission's fourth day.

NASA engineers also expressed concerns that pad hardware used to load propellants into the External Tank might leak, although these concerns proved unfounded. Otherwise, the attempt on 8 January proceeded relatively smoothly: the crew were on board Columbia by mid-morning, although the hold at T — 9 minutes was extended due to unsatisfactory weather at the SLF. In an effort to keep launch options open, the countdown continued to T— 5 minutes, before being held again. For a time, it looked like the weather might cooperate, but then a faulty electronics component signalled a potential problem with the water-fed sound-suppression system.

This system is activated when the main engines and SRBs are ignited and floods the launch pad surface with water from a series of giant 'rainbirds' to reduce the reflected soundwaves at the moment of liftoff. A team of engineers was sent out to the pad to check the electronics component and were satisfied that it was aligned correctly. However, ultimately, the weather closed in and led NASA managers to scrub the attempt. ''Even if they had not had that mechanical problem,'' said US Air Force meteorologists' spokesman Ron Rand, ''it was still 'no-go' for weather.''

ONE DOWN, ONE TO GO

Brandenstein's crew had more luck next day and Columbia thundered into space right on the opening of the hour-long launch window at 12:35 pm. A perfect ascent established them on an orbital racetrack to catch up with the LDEF and retrieve it on 12 January. In the meantime, the astronauts spent their first day in space concentrating on two major objectives: checking out the RMS - which Dunbar called ''a beautiful piece of hardware'' - and preparing to deploy Leasat. Affixed to a support structure called the Airborne Support Equipment (ASE) in Columbia's payload bay, the deployment was under Low's supervision.

At 1:18:39 pm on 10 January - a little under 25 hours after launch and on Columbia's 17th circuit of Earth - the satellite was released as the Shuttle flew over

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