Space Truck

Preparations for the STS-5 mission took place on three separate fronts. Firstly, there was the assembly of the boosters and External Tank, which took place in the VAB. Secondly, there was the processing - and a good deal of modification, too - of Columbia herself in the OPF. Finally, on this first operational flight of the Shuttle, the astronauts would be required to deploy two commercial communications satellites: Satellite Business Systems (SBS)-3 and ANIK-C3. Both arrived by aircraft at Cape Canaveral Air Force Station in the midsummer of 1982 and were quickly transferred to the Vertical Processing Facility for pre-mission checks.

Columbia, meanwhile, was having old parts removed and new parts installed. The IECM and the Canadian-built RMS mechanical arm - which would not be required on STS-5 - were removed, the pyrotechnics for the ejection seats were dismantled and two collapsible Mission Specialist seats were fitted. The final removal of the ejection seats was planned for an extended period of modification and refurbishment of Columbia, expected to begin after the Shuttle returned home from her STS-9 mission. Furthermore, the middeck floor was strengthened and parts of the DFI pallet were removed from the payload bay.

On 9 September 1982, Columbia rolled into the VAB and was attached to her tank and boosters. Following the now-customary verification of mechanical and electrical interfaces between each component, the butterfly-and-bullet stack was transferred to Pad 39A on the 21st. The two satellites and their attached solid-rocket motors - encased in a pair of lightweight sunshades - were moved to the pad on 12 October and loaded on board Columbia a week later. This procedure, which employed a device known as the Payload Ground Handling Mechanism, was the first time a piece of cargo had been loaded vertically into its launch vehicle.

It was a sign of things to come. The Shuttle, as advertised, was capable of carrying up to three communications satellites, together with their motors and sunshades, in her cavernous payload bay and NASA hoped that this could bring in millions of dollars of revenue each year. The launch of just two satellites by the STS-5 crew would net the space agency a first royalty payment of $18 million. Ultimately, it was hoped to out-compete for commercial contracts with the recently inaugurated European-built Ariane expendable rocket by offering 'free' seats on board the Shuttle to customers' representatives.

Looking 'down' on Columbia's payload bay, it seemed that two oversized versions of Pacman were sitting there, for when the protective sunshades opened to release the satellites inside, they looked just like a pair of jaws from the children's board game. Fortunately, unlike the real Pacman, these jaws were designed to release something, rather than gobble it up. Each cradle was composed of a series of aluminium tubes, covered with Mylar insulation, and measured 2.4 m long by 4.6 m wide across the width of the payload bay.

At the base of the cradle was a turntable to impart the required spin rate, which could vary between 45 and 100 rpm, depending on the payload, and a spring ejection system to release the satellite and its attached motor. During the Shuttle's ascent into orbit, a pair of restraint arms held the precious satellite steady inside the sunshade.

The ANIK-C3 communications satellite inside its 'Pacman' cradle before STS-5.

Soon after achieving orbit, the delicate shades were closed to protect the unpowered satellites from the space environment.

It was at this point that Lenoir and Allen would respectively supervise the deployment of 'their' individual satellite. The SBS-3 deployment, which would occur eight hours after launch, would be conducted by Lenoir and that of ANIK-C3 would take place under Allen's auspices almost exactly 24 hours later. As each astronaut performed 'his' deployment, the other Mission Specialist would photo-document the procedure, while Brand and Overmyer handled Columbia's systems and prepared to manoeuvre her safely out of the way before the satellites' motors were ignited to boost them into geosynchronous transfer orbits 36,000 km above the equator.

The 600-kg SBS-3 satellite was built by the Hughes company at its El Segundo plant in California and, when operational, provided all-digital voice, data, video and email facilities, a high-quality messaging service for business customers and a spare transponder for communications firms, broadcasters and cablecasters. Sitting just behind SBS-3 in Columbia's payload bay was ANIK-C3, which was more or less identical in size, shape and mass, but was owned by the Ottawa-based Telesat

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