Spain or Earth orbit

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The problems during launch on 29 July led to the first (and, to date, only) Shuttle Abort-to-Orbit (ATO) situation. The first stage performance (SRB and SSME) was reported to the crew as low, and meant that the SSME had to be throttled up to compensate for the problem. At 3 minutes 30 seconds into the flight, the first signs of a main engine problem were noted and at 5 minutes 45 seconds, the No. 1 engine failed and shut down, triggering the Abort-to-Orbit sequence using the remaining two engines. Challenger limped to orbit, which was gradually raised over the following twenty-four hours to allow the flight crew to accomplish most of the planned mission objectives. The events of the 51-F ATO were detailed in the companion volume Disasters and Accidents in Manned Spaceflight [David J. Shayler, Springer-Praxis, 2000, pp. 139-144] and are not reproduced here. However, the three former scientist-astronauts aboard the mission offered their own perspectives of these events.

On the 12 July launch attempt, Tony England was seated on the mid-deck, his main concern during the ascent being the safety of the payload specialists. The two PS were not as familiar with the systems as he was, and as the launch sequence progressed, England mentally reviewed his responsibilities and recalled his emergency training, just in case. When the abort situation arose, the crew was aware that this might not be a simple engine shutdown. Sitting out on the pad, England, like the rest of the crew, was more concerned with performing his assigned tasks than worrying about not reaching space that day. It was not until after they got out of the orbiter that the disappointment set in, but only for a short while. According to England, the crew went to Disneyworld to relax in the days after the pad abort while the engineers recycled the mission to attempt the launch again as soon as possible.

Up on the flight deck, Musgrave's concerns over the method of Shuttle ascent were affirmed by the abort. His intense training for flight deck activities on ascent and entry added to his knowledge (and concerns) about what could go wrong leaving Earth and getting home again. When the ATO call came in, Musgrave briefly thought that the simulation controllers were throwing in an abort situation on a real flight, but their training and knowledge of the systems gave the flight deck crew (Fullerton, Bridges and Musgrave) a good indication of what had happened, even before Houston gave the ATO call. Musgrave was already working on supporting Fullerton and Bridges with calls and procedures, should they need to abort the mission and fly over the Atlantic to an emergency landing in Rota, Spain.

He was so engrossed in the flight manuals on his lap that he was not immediately aware of a call from Karl Henize, who was sitting beside him in the fourth flight deck seat. He asked Musgrave where they were going, finding it hard to believe that after the pad abort he still might not make it into space. Although no one else seemed concerned, he wanted reassurance that he would finally get there. Without thinking, and deep in concentration over transatlantic abort sites, Musgrave replied ''Spain,'' causing both Fullerton and Bridges to quickly glance in amazement at the flight

The Abort-to-Orbit control is clearly displayed in this photo of the flight deck controls of Challenger after the STS 51-F launch suffered the loss of a main engine.

engineer. Musgrave had automatically answered Henize's question without really hearing him, but quickly calmed the situation - and Henize's fears - by telling him to relax. The astronomer would indeed make it to orbit - just. Years later Musgrave did state that it was "frightening" to some degree, as not all the engineering information was available to the crew. They were not fully aware of what the ground were seeing, or what was happening at the back of their vehicle. The reason for the abort (either on the pad or in-flight) was unknown to the crew; they were only aware of the shutdown or failed engine situation and had to follow procedures to overcome the problem.54

During the ATO situation, England, down on the mid-deck, was fully aware of what had happened and what was unfolding up on the flight deck. Once placed in a stable orbit, the concern for the crew was that somebody would find something that would force an early termination of the mission. The crew was aware that the controllers and engineers would analyse the data and determine the available options for either a short flight or a full-length mission. The main concern on orbit was over how much fuel would be needed to raise the orbit sufficiently to warrant staying there and what quality of scientific data would be obtained (or lost) as a result. Fortunately, the call came up from the ground that they were indeed safe in orbit and although some work needed to be done, a full mission would be flown. It had been a close call, but three former scientist-astronauts were in orbit on the same mission. Musgrave had survived a second ride of the solids and England had been the only astronaut to have left the astronaut programme without a flight and then come back and fly a mission (in 1997, John Glenn became the first flown astronaut to retire, return and fly, aged 77). Karl Henize, an avid astronomer since he was a boy, had finally made it to space aged fifty-eight, although he often said that the launch abort had added ten years to his real age!

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