Birth Pains

With less than eight weeks to go before her first orbital flight, Space Shuttle Columbia finally got the chance to flex her muscles on 20 February 1981. By now, the Shuttle was running three years behind its advertised schedule; its first launch was originally targeted for 1978 and its highest-profile mission - a delicate orbital ballet to reboost America's Skylab space station and prepare it for reoccupation -had been missed. Unexpectedly fierce solar activity in the closing months of the decade caused Earth's atmosphere to inflate, increasing air drag at orbital altitude and Skylab burned up during re-entry in July 1979.

Billions of dollars had been invested in the Shuttle, which was to be the most advanced spacecraft yet to depart Earth. The achievement had not, however, come without problems. Since the original contracts to build the Shuttle had been signed almost a decade earlier, its designers had faced setback after setback: frustrating problems with the development of a patchwork of heat-resistant tiles to shield it during its searing, high-speed re-entry and maddening failures of its throttleable, liquid-fuelled main engines. There was political fallout, too, with the Shuttle's powerful Congressional opponents questioning the need for a multi-billion-dollar reusable manned spaceplane.

For this was another of its advertised qualities: the Shuttle, said NASA, would be the world's first reusable manned spacecraft, capable of flying once every fortnight and carrying commercial satellites, scientific laboratories, space probes, astronomical instruments and - for the first time - ordinary civilians into orbit. Plans were already afoot to send teachers, journalists and foreign nationals into space, with up to seven seats available on each flight. The Shuttle, it seemed, was aptly named: it would whisk people into orbit frequently, reliably, relatively cheaply and in conditions a world away from the cramped, one-use-only capsules of the 1960s.

Before such an advanced machine could be declared 'operational', it had to be exhaustively tested. Many of these tests had taken place during and after its construction and a series of high-altitude approach and landing runs were conducted in mid-1977 using a dummy vehicle called Enterprise, taken aloft by an adapted 747 airliner. Fred Haise, one of her pilots, later called it ''a magic carpet ride''. Although she was never actually capable of flying into space and now sits gathering dust in the Smithsonian, Enterprise demonstrated the Shuttle's aerodynamic performance and ability to make precision landings on predetermined runways.

Ground tests, however, were no substitute for actually flying it in space. Original plans called for six Orbital Flight Tests (OFTs), each carrying two astronauts - a Commander and Pilot - to demonstrate the Shuttle's capabilities, test its manoeuvrability and evaluate its Canadian-built robot arm with different-sized payloads. The number of OFTs was later reduced to four, all of which would be flown by Columbia, the first space-rated Shuttle. Assuming that all four went to plan, the system would be declared 'operational' and become eligible to fly commercial missions on its fifth flight.

Columbia was physically identical to Enterprise, at least at first glance. Both vehicles were not dissimilar in shape and dimensions to the DC-9 airliner, roughly 36

m long with wings spanning 24 m from tip-to-tip, and comprising a two-tier cockpit, cavernous, 18-m-long payload bay with clamshell doors and an aft compartment to house a cluster of three main engines, bulbous Orbital Manoeuvring System (OMS) pods and vertical stabiliser fin.

Unlike Enterprise, however, Columbia would fly further than just the last few minutes from the low atmosphere to the runway. She would, for the first time, undertake the violent climb into space under the combined thrust of her main engines and two behemoth Solid Rocket Boosters (SRBs), withstand the swinging extremes of heat and cold in Earth orbit and bear the full brunt of a fiery descent back through the atmosphere. Moreover, in spite of carrying thousands of items whose failure could doom the Shuttle and kill the crew, Columbia's audacious first launch would be done with astronauts on board!

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