An 'Operational' Machine? Thirty Years Since STS-5 (Part 2)
With the completion of STS-5, NASA was able to publicly declare the Shuttle 'operational' for commercial and scientific missions. However, behind the scenes, its flaws were many and those flaws would grow and coalesce, producing the managerial, technical and cultural ingredients for disaster in January 1986. Photo Credit: NASA
Thirty years ago, this week, the Space Shuttle completed what NASA hailed as its first 'operational' mission. Columbia's STS-5 crew – astronauts Vance Brand, Bob Overmyer, Joe Allen and Bill Lenoir, the first four-man team ever launched aboard a single spacecraft – satisfactorily deployed two telecommunications satellites into orbit: one for Satellite Business Systems, the second for Telesat Canada. With the completion of these two remarkable objectives, they labelled themselves 'The Ace Moving Company' and proudly proclaimed their 'Fast and Courteous Service'. It was the dawn of a new age in human exploration, and exploitation, of the heavens, as the Shuttle sought to commercialise low-Earth orbit as never before. One other critical task lay ahead for STS-5: a full-up demonstration of the new Shuttle space suit…and an EVA which never came to pass.
The three-and-a-half spacewalk was scheduled for 14 November 1982, three days into the five-day mission. Lenoir (designated 'EV1', with red stripes on the legs of his suit for identification) and Allen (EV2, in a pure white suit) would become the first Americans to leave their spacecraft since the Skylab era and during their excursion they would test not only the suits, but also techniques to repair NASA's 'Solar Max' satellite on a dedicated Shuttle mission in early 1984. The astronauts had also trained to perform an emergency opening and closure of Columbia's payload bay doors. Preparations for the EVA required an entire day. Assisted by crewmate Bob Overmyer, they would have risen early to begin readying their suits and would have spent four hours 'pre-breathing' pure oxygen to wash nitrogen from their blood in order to avoid attacks of the bends. The airlock's pressure would have been reduced by around two-thirds and at 73 hours after launch Lenoir and Allen would have entered Columbia's floodlit payload bay to start work.
During the EVA, their every move would have been choreographed by Overmyer, whilst Vance Brand photographed the historic event. The spacewalkers' first task would have been to tether themselves to slidewires running along the sills of the payload bay walls, thus preventing them from floating away from the orbiter. Then, with Lenoir tethered to the starboard sill and Allen on the port side, both men would have translated down the entire 60-foot length of the bay to the aft bulkhead. During this time, they would have evaluated the comfort, dexterity, ease of movement and communications and cooling performance of the suits, as well as the floodlights mounted in the bay. They would have also assessed locations at which future spacewalkers could work to repair Solar Max. Practicing 'repair' techniques would have dominated Lenoir and Allen's time: after these initial evaluations, they would have returned to the forward end of the bay to begin work on a dummy set of Solar Max equipment. For more than an hour, they were to test and make comments on a series of fixed and torsion-adjustable bolts, using a special wrench.
Bill Lenoir (left, with red stripes on the legs of his suit) and Joe Allen prepare for an underwater training exercise. Allen would go on to perform two EVAs in November 1984 – participating in the triumphant salvage of the Palapa and Westar satellites – but for Lenoir the chance to venture outside the airlock would slip forever through his fingers. Photo Credit: NASA
Lenoir would then have moved to the Solar Max equipment – including a dummy main electronics box from the satellite's coronagraph instrument – to begin a procedure which was intended to be equally as complicated as it would be on the real repair mission. Assisted by Allen, handing him parts, Lenoir would have removed thermal blankets, taken off mounting bolts and connectors, cut a grounding strap and painstakingly reattached the connectors; encased in a bulky pressure suit, it would have been no mean feat. Although the Solar Max tests would have occupied a large portion of their time, the spacewalkers would also have evaluated a manual system for closing the payload bay doors. This involved a winch system, attached to the forward bulkhead, and they would have used it both with and without the benefit of foot restraints. They would also have moved a bag of tools and evaluated a small black-and-white television camera, mounted atop Allen's helmet; its postage-stamp-sized lens was expected to yield some impressive images from the EVA.
Unfortunately, none of this happened; at least, not on STS-5. In fact, no spacewalker would successfully leave Columbia's airlock until STS-87 in November 1997. Lenoir and Allen's EVA was initially postponed by 24 hours until 15 November when both Lenoir and Overmyer suffered a particularly severe dose of space sickness. Overmyer's suffering began on the second day of the mission. "He filled a couple of [vomit] bags," Lenoir told the NASA oral historian, "but I never stopped giving Bob credit. We had a bunch of engineering tests to do. Sitting up in the pilot's seat, taking data, doing this, that and the other, he never missed a step. He'd puke his guts out and he'd get back to work…and he felt crappy for two days!" Shortly after Overmyer began to feel bad, it was Lenoir's turn.
In subsequent conversations with physician-astronaut Bill Thornton, Lenoir felt that he had psyched himself up for the two satellite deployments, then allowed himself to relax; a wrong move. It felt, said Lenoir, very much like a low-grade hangover. He could work, but did not want to exert himself physically or mentally, other than to curl up and sleep it off. As circumstances transpired, that is exactly what happened. The EVA with Allen was delayed, allowing Lenoir some time to "sack out in the middeck".
Sacking out on the middeck also created another problem, as his three crewmates were granted the opportunity to raid Columbia's pantry…which included green jalapeños. Lenoir had a particular penchant for the hot chili peppers and grew them in his Houston backyard, frequently bringing bagfuls into work at the Johnson Space Center to munch whilst training. He would offer them to other astronauts and take pleasure at their reaction. On STS-5, Lenoir hoped to be able to playfully chew on them, particularly during televised broadcasts, but his brush with space sickness meant that most of his beloved jalapeños rapidly vanished instead into the mouths of his three crewmates…
Originally, the Shuttle was intended never to require an EVA capability. In the 1970s, it was regarded as the spacegoing equivalent of a commercial airliner…but when it became clear that problems might be experiencing closing the payload bay doors and attending to other technical issues, an EVA capability evolved. Many of the techniques for attending to contingencies would have been trialled by Lenoir and Allen on STS-5. Photo Credit: NASA
More trouble was afoot, however, when they tried again to perform the EVA on 15 November. When the men finally donned their suits and ran through the standard checks, a problem was noticed with Allen's ventilation fan; it sounded "like a motorboat". In effect, it was starting up, running unexpectedly slowly, surging, struggling and finally shutting down. Nor was Allen's suit the only one giving trouble. Lenoir's primary oxygen regulator – which would have been used during his pre-breathing exercises and throughout the EVA – failed to generate enough pressure. Some of the astronauts' helmet-mounted floodlights also refused to work properly. After fruitless efforts to troubleshoot the problems, the EVA was cancelled and deferred to the next Shuttle mission, STS-6.
Lenoir was bitterly disappointed. "I guess I was the bad guy," Vance Brand told the NASA oral historian. "I recommended to the ground that we [cancel] the EVA, because we had a unit in each space suit fail in the same way. It looked like we had a generic failure there. It was the first time out of the ship. We didn't want to get two guys – or even one guy – outside and then have [another failure]. We could have taken a chance and done it, but we didn't. I'm not sure Bill Lenoir was ever very happy about that, because he and Joe wanted to go out and have that first EVA."
As the chief spacewalker, Lenoir was upset at losing the chance to put months of EVA training to the test. He wondered if it was possible for just one of them to go outside. "We tried to talk them into it," he recalled, "but it was made more difficult by Joe being inop[erable], because now I'm trying to talk them into: not only are we going to go EVA with a suit that you don't really understand, but there's only oneperson going to be out there, so you don't have a buddy system."
"We didn't have to do the EVA." Joe Allen's words are aptly exemplified in the STS-5 crew patch which shows one of the primary foci of the mission: the two commercial satellites – SBS-3 and Anik-C3 – being successfully deployed from the payload bay. An EVA was additional icing and would be achieved by STS-6. Image Credit: NASA
To be fair, as Allen noted, they did not really have to do the EVA; the satellite deployments and a safe landing were their priorities. "On the day before the spacewalk," he said, "we commented to ourselves that we really had just twoimportant things [remaining] to do: one was the spacewalk and the second was the re-entry and a safe landing." Allen made the observation to Brand and both men agreed that they would prefer the safe landing! In Allen's mind, thebad news was that the suits had failed…but the goodnews was that they had notfailed whilst the men were outside in the payload bay. Had the worst happened, and a failure whilst outside had occurred, Allen was confident that it would not have been a fatal situation, but would have required him to scramble back into the airlock and get out of his suit before more failures piled up.
Immediately after STS-5 landed, on 16 November 1982, a task force, headed by Richard Colonna, manager of NASA's Program Operations Office, was established to investigate the problem. The fault in Lenoir's suit was ultimately traced to two missing 'locking' devices – each the size of a grain of rice – in his primary oxygen regulator. These allowed a locking ring in the suit to open, thereby triggering a pressure leak. According to paperwork, provided by the suit's manufacturer, Hamilton Standard, the locking devices were fitted and signed-off by a supervisor in August 1982, but actually had not been fitted at all and were not checked. The responsible employee, and the supervisor, were "barred from further NASA work", according toTime magazine's summing-up of the debacle on 20 December.
The absence of the locking devices allowed the pressure in Lenoir's suit to creep back. The problem in Allen's case was a faulty magnetic sensor in the fan electronics. Colonna's final report pointed out that "even with no improvements, if the regulator were fabricated properly, the PLSS [the Portable Life Support System, the suit's backpack] would function properly". It also listed ways to test and inspect future regulators and motors and recommended testing inside the Shuttle's airlock on the day before launch. Additional plans were set in motion to provide sensors with better moisture resistance for future motors and new tests to allow defects to be identified earlier.
With the disappointment of the cancelled EVA behind them, the astronauts spent the last few days completing experiments and preparing for the voyage home. Five days of work at breakneck speed had exhausted them. "Joe kind of ran himself out of gas the last day," Lenoir told the NASA oral historian, "because he wasn't sleeping real well and some combination of that. He needed to get some sleep." At one stage, Allen asked Lenoir to take over a student experiment he was working on. From Lenoir's perspective, having suffered space sickness, it was all part and parcel ofadapting oneself to the new environment…and that invariably took time. On a five-day mission, the men had barely enough time to acclimatise to the new conditions around them, before it was time to come home. Brains attuned to several decades of acquiring data from the eyes and ears – which way is 'up' and reorienting oneself, for example – were thrown temporarily into disarray. "Even today," Lenoir said, years later, "I have days where I realise this is a day where my brain won't listen to my ears…and at least I've figured that out and I don't close my eyes a lot in the shower, when I'm standing on one foot. Humans are humans."
Bill Lenoir, seen here trimming Bob Overmyer's hair, was bitterly disappointed at the loss of an EVA which he had committed so much of his time and energy throughout 1982. Yet the legacy of his work, and that of his crewmates, would endure as the Shuttle tackled ever more complex EVA tasks in the 1980s and beyond: repairing Solar Max, servicing Hubble and building today's International Space Station. By the time Lenoir died in August 2010, no fewer than 156 EVAs would have been successfully completed from the Shuttle. Photo Credit: NASA
It had been hoped, initially, to land Columbia in a crosswind at Edwards Air Force Base in order to evaluate the Shuttle's handling characteristics under duress, but instead the spacecraft would touch down in California under calm weather conditions. The re-entry was particularly dynamic from the astronauts' perspective and photographs taken by Allen from the flight engineer's seat, looking over the shoulders of Brand and Overmyer, recorded a hellish, pinkish-orange glow outside the front windows.
As Columbia slowed from an orbital velocity of Mach 25 down to around Mach 20, it was possible to see sweeping white 'beams', or shockwaves, rippling across the Shuttle's nose. At Mach 18, still travelling at more than 12,000 mph, Brand took manual control and performed a flight test manoeuvre. He pushed down from a 40-degree angle of attack to 35 degrees, then up to 45 degrees, and back to 40 degrees. This 'Push-Over-Pull-Up' exercise had been demonstrated during earlier Shuttle test flights. "When I did that," he explained later, "Joe Allen said a shockwave came from the nose and attached to the windows right in front of us! That was a little worrisome, because he knew it was hot, but then about as soon as it got there I was on my way to a higher angle of attack, so it 'walked' back to the nose."
Thanks to Allen and his camera, many of these astonishing images – "interesting things", according to Brand – were captured for posterity. Several images found their way into Allen's 1986 book about his experiences, Entering Space. "There's a wonderful one of Bob Overmyer's face being silhouetted by the orange glow," Allen recalled, "and there's another one of Vance Brand." Other images were shot through the overhead flight deck windows and reveal astonishing flickers of white-hot plasma as the orbiter knifed her way hypersonically towards a landing strip, halfway across the planet. "The engineers were very interested in that," Allen wrote. "They'd neverseen it before."
The first real indication of entrance into the atmosphere, Allen wrote, came when the needle of the G-meter on the instrument panel, which had been fixed at zero for five days, suddenly began to quiver, shook itself to life and began steadily climbing. In his book, he vividly described the descent through the steadily thickening atmosphere, as Columbia's computers rolled the vehicle to the left and to the right, gradually bleeding off velocity through a series of wide, sweeping turns. "As the orbiter banks into a left turn," he wrote, "the crew on the flight deck watches in the forward windows the distant, dim horizon turn until it is almost vertical. Then, as the autopilot commands a bank reversal from left to right, the crew watches the line of the horizon roll until it is momentarily level again, then continue to roll until the right limb of the horizon disappears out the top of the window and the left limb falls away and is hidden by the orbiter's nose." The small reaction control thrusters continued to be pulsed for corrections along the way, but were gradually phased out as Columbia descended further into the thicker air and the role of its aerodynamic surfaces – the elevons on the wings for pitch and roll, the rudder on the vertical stabiliser for yaw and speed braking – became effective. The onset of gravity, Allen wrote, pushed him against his seat; he could feel increasing pressures on his thighs and back as the deceleration continued. After almost a week in microgravity, he now felt more than double his normal Earthly weight. It was not extremely uncomfortable, but definitelynot a pleasant experience.
"When you get down to Mach 2," Brand said, as the orbiter fell, brick-like, "you're getting into thick atmosphere and it's rumbling outside…you can hear it rumble and you're decelerating such that it's pushing you into your straps." On reaching the west coast of the United States and crossing over Monterey Bay, Brand, Overmyer and Allen beheld the first glimmers of a pale desert sunrise over the eastern horizon.
Accompanied by a T-38 Talon jet, Columbia approaches the landing site at Edwards Air Force Base in California on 16 November 1982. Photo Credit: NASA
Passing over California's Tehachapi Mountains, the orbiter went subsonic with a pair of sonic booms, sounding like 12-gauge shotguns. "We went through a very thin cloud deck," Brand said. "I was on instruments flying and circled down and landed at Edwards." The touchdown, which came at 6:33:26 am PST (9:33:26 am in Florida), was immediately followed by a test of Columbia's maximum braking capabilities. However, the left-hand main inboard wheel 'locked up' during the final part of the rollout, due to a brake failure. "We completely ruined the brakes," remembered Brand. "I had to stomp on them as hard as I could, which points out that we had a lot of flight test on the mission. Even thought it was the first commercial flight, I think we had 50-50 test objectives. That braking test was just one of them. We ruined the brakes – completely ruined them – but it was a test to see how well they would hold together if you did that."
Thirty years ago, this week, NASA welcomed home the STS-5 crew, after a bittersweet five days in orbit. The Shuttle's first EVA would have to wait for a few more months to be realised, but the mantra that it had now evolved, chrysalis-like, into a commercial space 'truck' seemed vindicated. It was an astonishing accomplishment when one considers that the first flight of the vehicle – a vehicle far more complex than any other in human history – had occurred barely 18 months earlier. Yet the designation of 'operational' was a misleading one; misleading in the sense that it presented the Shuttle as the spacegoing equivalent of a commercial airliner, misleading in that it presented the Shuttle as a craft which could make human access to space 'routine'…and, most damning of all, misleading in that it reinforced the Old Lie: that reaching and exploring the Final Frontier could ever be truly safe.
This is part of a series of History articles which will be published each weekend, barring any major news stories. Next week's article will focus on STS-51A, a mission in November 1984 in which Joe Allen finally realised the opportunity to perform an EVA…and helped secure for NASA one of its grandest publicity coups.
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