RocketSTEM Issue #2 - April 2013 | Page 38

a concept that came to be known as ‘the parasol’. Tests showed that a combination of coiled springs and telescoping rods could fit inside a standard airlock experiment canister and could be deployed smoothly. Jack Kinzler, chief of the Johnson Space Center’s technical services division, a close friend and neighbour of Conrad, developed the system by jury-rigging it from a parachute canopy and telescoping glass-fibre fishing rods in hubmounted springs. During a final review at the Kennedy Space Center on 19 May, Kinzler’s parasol was accepted as the primary method and on the 24th the flight readiness review endorsed it. Having an astronaut standing in the hatch on an EVA was undesirable, since it would come at the end of a long, 22-hour day for the crew. Equally, the twin-pole concept did not meet with the approval of the flight surgeons, who were aghast at the prospect of such a complex task so early in the mission, before the crew had properly acclimatised to weightlessness. However, Conrad felt that Kinzler’s design was the simplest, safest and quickest method…and most likely to succeed. Years later, Schweickart glowingly praised the efforts of the industrial and NASA workforces to save Skylab during those frantic days of May 1973. “I probably got a little bit of sleep,” he recalled, “but most of the team who worked with me at Huntsville never slept for four days! It was totally round-the-clock and it was not just the resources of the centre; it was all of the resources of the whole aerospace industry.” Kerwin felt the same. “It was a great team,” he reflected. “I look on Apollo 13 as the supreme test… for the Mission Control team. The Skylab problem was the supreme test for the engineering team. Both the contractors and the civil servants joined together, as one, and they figured out what the problem was.” Of course, the state of the arrays and the reason for the No. 2 array being unable to properly un- 36 36 Close up view of Skylab 2 Crewmember Joseph P. Kerwin performing an extravehicular Photo: NASA via Retro Space Images activity (EVA), probably to repair the covering. furl, could only be speculated until the arrival of Conrad’s crew and the presence of three sets of eyes to physically see what was amiss. If debris was the problem, a repair method was acutely needed and engineers from the Marshall Space Flight Center set to work to adapt a cable cutter (not dissimilar to a heavy-duty tree lopper) and a universal tool with prongs for prying and pulling to open the jammed array. On 19 May, the tools were successfully tested in Marshall’s neutral buoyancy tank, with the Skylab mockup specially ‘modified’ with fragments of metal wire bundles, shards of bolts and other objects representative of a failed micrometeoroid shield. Conrad, Kerwin and Weitz took their turns underwater, evaluating the tools, practicing prying the debris away from the array and completing the whole procedure safely. The tools had already left for the Kennedy Space Center when a certification review ruled that the pointed tips of the cutter were hazardous. New heads with blunt tips were quickly prepared and the change was made at the launch site. Now, however, the time for talking was over. Years later, in her book Rocketman, Nancy Conrad related that Pete’s response to the seemingly endless testing was typically to the point: “Just get me up there!” With their launch scheduled for the stroke of 9:00 a.m. EST, the morning of 25 May 1973 was particularly peaceful for the three astronauts. “This was the least well-attended Apollo launch in history,” Kerwin recalled, “because everybody had to go home and put the kids back in school. We arrived at the command module and looked inside and it was a sea of brown rope under the seats and under the brown www.RocketSTEM.org