Room For Improvement

Columbia's exact landing time was 4:04:46 pm on Runway 17, setting a new Shuttle duration record of just over eight days. As the gypsum-coated Shuttle sped down the runway, with her forward landing gear in the process of coming down, the nose unexpectedly pitched back up into the air, again providing a moment of shocked surprise among the assembled spectators at White Sands. The effect, as Fullerton would later remark, was ''a kind of wheelie''. The astronauts, it seemed, were trying to prevent what they thought was a premature nosewheel touchdown.

''It pointed out another flaw, or room for improvement, in the flight software,'' Fullerton would say later. ''The gains between the stick and the elevons, that were good for flying up in the air, were not good when the wheels were on the ground. He [Lousma] kind of planted it down but then came back on the stick, and the nose came up. A lot of people thought this is a terrible thing [but] we improved the software and so people don't do that anymore; but we discovered a susceptibility.''

Despite the concerns expressed by NASA management at the time, STS-3 was still a test flight - and such problems are commonplace on test flights - as well as only the third mission of the world's most advanced and complex spacecraft. The achievement was that the astronauts identified the problem before the Shuttle went operational and additional simulator runs by the STS-4 crew would use the 60-m altitude mark, rather than 500-km/h airspeed, as their cue to deploy the landing gear. The key points of STS-3's landing were that it was safe and it was successful.

Charlie Bolden watched the landing attentively. ''Everything seemed to be going well until just seconds before touchdown, when all of a sudden we saw the vehicle kinda pitch up and then kinda hard nose touchdown. We found out that just as Jack Lousma had trained to do, you need to move [the control stick] an appreciable amount [to disengage the autopilot]. We didn't realise that. The way he had trained was just to do a manual download with a stick. When he did that, he disengaged the roll axis on the Shuttle, but he didn't disengage the pitch axis. So the computer was still flying the pitch, although he was flying the roll. Gordon Fullerton just happened to look at the eyebrow lights and he noticed that he was still in auto in pitch. He told Jack and so Jack just kinda really pulled back on the stick, and it caused the vehicle to pitch up. Then he kinda caught it and put it back down and he saved the vehicle.''

As servicing vehicles encircled Columbia, the spacecraft sat on the runway, in Fullerton's words, ''surrounded by white gypsum''. So severe was the damage that the flow rate from the purge units attached to the Shuttle's forward fuselage was increased and the aft compartment's vent doors were closed to prevent further contamination. On hand at White Sands to greet the astronauts, in addition to their families, were New Mexico Governor Bruce King and former Apollo astronaut Senator Harrison 'Jack' Schmitt, as well as the missile range's commanding officer, Major-General Alan Nord.

Within hours of landing, Columbia's time-critical experiments, including the plants from the PGU and samples from the Electrophoresis Equipment Verification Test (EEVT), were removed from the middeck and returned to their research teams. The EEVT unit was a forerunner of later Shuttle experiments, which would employ 'electrophoresis' - whereby electric currents separate biological materials in fluids without damaging the cells themselves - to allow scientists to conduct studies of cell biology, immunology or for medical research. Electrophoresis on Earth is difficult because heat produced by the electric current introduces buoyancy and remixing of the cells and fluids, thus defeating the objective.

During STS-3, the unit held red blood cells and live kidney cells which the astronauts inserted into a series of glass columns for the separation process to take place. After an hour, the samples were removed and stored in a cryogenic freezer for the journey home. Unfortunately, at some point over the weekend of 3-4 April, as they underwent preparations to be flown back to NASA's Johnson Space Center in Texas for analysis, the freezer suffered a failure and thawed the samples, thus ruining them. It was an intense disappointment for the EEVT scientists.

Columbia, meanwhile, was towed to a huge crane known as the Stiffleg Derrick, which - with the assistance of a conventional crane - hoisted her on top of the 747 carrier aircraft for the return flight to Florida. At 2:00 pm on 6 April, the Shuttle left White Sands and, following a refuelling stop at Barksdale Air Force Base in Louisiana, touched down at KSC just six hours later. Had she returned to Edwards as originally intended on 29 March, her return to Florida was not anticipated before 9 April.

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