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'It's Gonna Be Great': 30 Years Since Shuttle Mission 51D (Part 1)
By Ben Evans, on April 4th, 2015


Spacewalkers Jeff Hoffman and Dave Griggs work to outfit a makeshift fly swatter onto the Remote Manipulator System (RMS) mechanical arm, in a fruitless attempt to activate Syncom 4-3’s deploy switch. Photo Credit: NASA

None of the 135 missions flown by NASA’s five-strong fleet of shuttle orbiters between April 1981 and July 2011 could ever be classified as “routine” and all contributed greatly to our exploration of space. However, if there was one flight which actually proved a little more colorful than originally intended, it would be Mission 51D, the fourth voyage of Discovery, which launched 30 years ago, next week. As detailed in an earlier AmericaSpace history series, the flight originated as Mission 41F, targeted for launch in August 1984, but was canceled in the aftermath of the shuttle program’s first on-pad launch abort. The crew—Commander Karol “Bo” Bobko, Pilot Don Williams, Mission Specialists Rhea Seddon, Dave Griggs, and Jeff Hoffman, and Payload Specialists Jake Garn and France’s Patrick Baudry—were reassigned to Mission 51E, scheduled for early March 1985, which was itself canceled only days before launch, due to payload problems. At length, they found themselves earmarked for Mission 51D in mid-April. At face value, their payload looked relatively “vanilla,” but the dramatic Mission 51D would prove far from ordinary.

In fact, Mission 51D should have been a totally different flight with a totally different crew. Scheduled for launch later in March, it would have deployed the U.S. Navy’s Syncom 4-3 military communications satellite and retrieved NASA’s Long Duration Exposure Facility (LDEF) after almost a year in orbit. With the cancelation of 51E, the LDEF commitment was dropped from 51D, a second communications satellite—Canada’s Anik-C1—was added and there existed great media speculation that Bobko’s crew might receive assignment to the “new” 51D flight. They had trained for both Syncom and Anik deployment procedures, but the perspective of the crew was that they simply wanted to fly. “It was a stressful time,” Rhea Seddon remembered. “For most of us, it was our first flight and we didn’t care what they did to us, as long as they launched us!” The identities of the two Payload Specialists were also subject to change. By early April, Baudry had been bumped to a later mission and replaced by McDonnell Douglas engineer Charlie Walker—a member of the “original” 51D crew—whose company’s electrophoresis machine had already been installed onto the middeck of Shuttle Discovery.

On 12 April 1985, four years to the day since the first shuttle launch, the seven astronauts trooped out to Pad 39A, under very murky skies and a light drizzle, to board Discovery. Launch was scheduled for 8:04 a.m. EDT, on the opening of a 14-minute “window,” although a second opportunity ran from 8:45 until 9:00 a.m. “The weather was a little shaky,” Don Williams remembered, “because there was an overcast at about 12,000 feet (3,600 meters) or so. We didn’t think we were going to go and we were kind of just chatting around … because we figured we were going to do a scrub turnaround for 24 hours and come out the next day.” In fact, Dave Griggs, the flight engineer, had unstrapped and was sitting on the backrest of his seat, talking to Hoffman, Walker, and Garn on the middeck.



Flying Mission 51D, the crew finally launched on 12 April 1985, carrying the first serving politician into orbit … and embarked on a mission which proved unexpectedly dramatic. Photo Credit: NASA, via Joachim Becker/SpaceFacts.de

A freighter, the Ocean Mama, strayed into the drop zone for the boosters and had to be shooed away by the U.S. Coast Guard, causing a delay of almost an hour. As the second window opened with the clock in a planned hold at T-9 minutes, the crew were convinced that the attempt would be scrubbed. All at once, at 8:50 a.m. EDT, the call from the NASA Test Director in the Launch Control Center (LCC) crackled over the radio: an extension to the window had been granted and the clock was being manually restarted. Quickly, Hoffman strapped Griggs back into his seat and clambered downstairs to his own seat, next to the side hatch. “It was probably T-2 [minutes] before I really knew that I was finally going to go,” Hoffman recalled, “and then I was all psychologically set to go. That’s a very exciting time. Lots of things are happening. The shuttle is really alive and it’s moving!”

Jake Garn turned to Charlie Walker to ask what to expect.

“It’s gonna be great, Jake,” came the reply. “Just stay calm and enjoy it.”

Upstairs, from the pilot’s seat, Williams could see thick grey clouds; intellectually, he knew that they would not normally launch in such conditions, for fear of moisture damage to the orbiter’s thermal protection tiles. The launch itself, which came at 8:59 a.m. EDT, was “sort of like a two-minute-long catapult launch.” As they burst through the top of the cloud deck, he asked Bobko, half-jokingly, if he should give Mission Control a “tops report.” The commander responded with a curt “Shut up and watch your instruments!”

From Hoffman’s perch, the vibrations were one of the strongest sensations—reaching such intensity at one stage that he was convinced that Discovery’s wings were about to fall off, but the steady change from blue sky to black and the magical onset of weightlessness were profound. Numerous flights in the KC-135 parabolic aircraft had attuned his senses to the unusual environment, but now he was in a permanent state of free-fall. “That’s when it really hit me,” he said. “I floated over and I looked out the window and there was the Earth going by. You could see Africa off in the distance. Then I looked in the mirror and there was me in space. I just got this big ear-to-ear grin and I just couldn’t stop smiling for several hours! It was just such an elation.”



Mission 51D launched into space on 12 April 1985, the 24th anniversary of Yuri Gagarin’s pioneering flight. Photo Credit: NASA

For now, on 51D, five rookies were able to acclimatize themselves to their surroundings, but it soon became evident that Walker and Garn had been affected by space sickness. “I could tell that Jake’s feeling it about as rough as I am,” Walker recalled in a NASA Oral History, “and … this is my second experience and I had anticipated that, yes, I’ll probably have the same kind of symptoms and that was the case. Jake didn’t know what to expect.” Both Payload Specialists kept their movements to a minimum, avoiding so-called “zinging of the gyros” by moving their heads around too much in the first few minutes of orbital flight, but Garn’s reaction to the space environment was one of the most profound ever seen. One flight surgeon later joked that the “Garn Unit” had been created as a measure of nausea in astronauts. Clearly, Garn experienced severe space sickness and some rumors suggested that he was even incapacitated for a few days. “He has made a mark in the astronaut corps,” remembered oceanographer Bob Stevenson, “because he represents the maximum level of space sickness that anyone can ever attain … and so the mark of being totally sick and totally incompetent is ‘One Garn’. Most guys will get maybe a tenth [of a] Garn.”

Meanwhile, the first payload, Canada’s Anik-C1, was deployed at 6:38 p.m. EDT, almost 10 hours into the mission, and the camera on the shuttle’s Remote Manipulator System (RMS) mechanical arm captured the successful firing of its Payload Assist Module (PAM)-D motor shortly thereafter. Bobko and Williams performed a separation burn, which also served to slightly raise Discovery’s altitude in readiness for the release of the Navy’s Syncom 4-3 early the following morning. This did not go well. At 9:58 a.m. on the 13th, the giant satellite rolled out of the payload bay, but as it drifted away its omni-directional antenna failed to unfurl. Its anticipated “spin-up” maneuver to 33 rpm also failed to occur, and, 45 minutes after deployment, its solid-fuel perigee kick motor did not fire.

“We sort of looked,” Hoffman recalled. “Once we launch it—once it’s left the shuttle—our responsibility is finished. We moved away, just in case the engines fired, but of course they didn’t. Then, already on the ground, they were starting to think about contingencies. They told us to do another burn, because otherwise we would have kept moving further and further away from it.”



The Syncom 4-3 satellite drifts away from Discovery. The failure of its omni-directional antenna to deploy and of its solid-fueled perigee kick motor to ignite led to an impromptu rendezvous and repair attempt. Photo Credit: NASA

By the third day of the mission, consensus had been reached that an attempt would be made to revive Syncom 4-3. The flight was extended by 48 hours from five to seven days to accommodate this effort. The crew had followed their procedures correctly and the only possible cause of the failure was something called a “deploy switch,” which should have popped open as the satellite rolled out of the payload bay and triggered a timed sequence of events, leading up to the ignition of the perigee kick motor. On the ground, the switch was held in position by a piece of foam rubber and it appeared likely that this had not been removed before flight.

Fortunately, it was an external switch and Mission Control felt that a contingency EVA by Hoffman and Griggs might be able to trip it. The astronauts barely remembered the switch. They had visited the factory, many months earlier, when their original Mission 41F included a Syncom as part of its payload, but did not recall ever having been shown the deploy switch. However, that was only part of the problem now facing Bobko’s crew. They were being asked to re-rendezvous with Syncom in order to enable Hoffman and Griggs to conduct their spacewalk and Seddon to use the RMS to trip the switch.

Almost a year had passed since the cancellation of Mission 41F, which originally included a rendezvous with a free-flying Spartan satellite. Their mission had long since changed and their rendezvous skills were now rusty. “We had not done a rendezvous simulation … in seven months or so,” Bobko told the NASA oral historian, “and we didn’t have the books to do the rendezvous, so they sent us up this long teleprinted message.” The message was then cut up and pasted into their unneeded post-insertion checklist to create a makeshift rendezvous book. Moreover, although Hoffman and Griggs had done contingency EVA work in support of Spartan—in the region of 50 hours or more—none of it was recent and none of it was in direct support of Mission 51D’s payloads. Since an EVA was not planned, no mobile foot restraints were aboard the shuttle, and efforts by astronauts in the Weightless Environment Training Facility (WETF) at the Johnson Space Center (JSC) in Houston, Texas, to identify workarounds proved unsatisfactory.

It would be a tricky—and highly risky—task.


Source: https://www.americaspace.com/2015/04/04/its-gonna-be-great-30-years-since-shuttle-mission-51d-part-1/

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Odp: [AS] 'It's Gonna Be Great': 30 Years Since Shuttle Mission 51D
« Odpowiedź #1 dnia: Czerwiec 20, 2019, 14:12 »
'Vide Mater, Sine Manibus': 30 Years Since Shuttle Mission 51D (Part 2)
By Ben Evans, on April 5th, 2015


Displaying their impromptu flyswatters, “Bo’s Swat Team” gathers for an in-flight portrait. From left to right are Jake Garn, Jeff Hoffman, Don Williams, Rhea Seddon, Karol “Bo” Bobko, Dave Griggs, and Charlie Walker. Photo Credit: NASA

Thirty years ago, next week, the crew of Mission 51D watched open-mouthed as a powerful communications satellite which they had just deployed seemed to fail, right before their eyes. The U.S. Navy’s Syncom 4-3 had rolled, in a frisbee-like fashion, out of Shuttle Discovery’s payload bay, without incident. Then, as described in yesterday’s AmericaSpace history article, things started to go wrong. Its omni-directional antenna failed to unfurl. Then its “spin-up” maneuver to 33 rpm failed to occur. Finally, 45 minutes after deployment, its solid-fueled Perigee Kick Motor (PKM) failed to ignite. NASA elected to re-rendezvous with the satellite and attempt to activate its deploy switch, and rendezvous procedures were transmitted to the shuttle’s teleprinter. The next step was a hazardous EVA—the first “contingency” EVA of the shuttle era—which required the crew to use a makeshift fly swatter to activate the switch.

“Rendezvous in space is a fairly complicated process,” explained 51D Pilot Don Williams. “It’s not like formation flight, where you just join up with another airplane, because you have to take orbital mechanics into effect and there are several maneuvers and burns … that have to be done at very precise times in order to keep from either overshooting it or crashing into or missing the thing entirely.” As Williams and 51D Commander Karol “Bo” Bobko handled the intricate rendezvous, the other NASA members of the crew—Mission Specialists Rhea Seddon, Dave Griggs, and Jeff Hoffman—worked to assemble a makeshift “flyswatter,” which would be attached to the end of the shuttle’s Remote Manipulator System (RMS) mechanical arm to hopefully trip the deploy switch.

Mission Control uplinked typed directions to the shuttle’s teleprinter, and the astronauts used the plastic covers of procedures books, sections of aluminum swizzle sticks, metal pieces from the interdeck access panel, and a roll of gray duct tape to put together the impromptu device. Seddon cut the sticks with a bonesaw—a procedure which she later described as “arts and crafts time”—whilst Payload Specialist Charlie Walker vacuumed up the chippings. On 16 April 1985, four days into the mission, Hoffman and Griggs were suited up and departed Discovery’s airlock. “I was the first one out,” said Hoffman. “It was just when the Sun was setting, so the whole shuttle was lit up red and it was just so spectacular.” The experience felt quite similar to the underwater simulations … and that brought back another memory. Before launch, he and Griggs had told the neutral buoyancy staff that if they were called upon to do an EVA, the astronauts would pay for the beer.

It was a joke, of course, but Hoffman knew that they would have to pay up. After all, it would be worth it.

The two men were outside for a total of three hours and six minutes, fitting the flyswatter onto the end of the RMS, which Seddon then extended toward Syncom 4-3’s deploy switch. Charlie Walker watched the proceedings with amazement. He had been forced to temporarily shut down his electrophoresis experiment on the middeck when the cabin pressure was reduced in preparation for the EVA. “Remembering that none of this had been practiced on the ground,” he later told the NASA oral historian, “that this was all done just with the skills that the crew had been trained with generically … and yet the crew pulled it off expertly.” The deploy switch was successfully tripped—in fact, Seddon managed to acquire three good contacts with the flyswatter as the satellite slowly rotated—but, alas, it did nothing to bring the satellite to life.

The fix had not worked; obviously, the fault lay not just with the switch, but possibly also with an electronics failure in the satellite itself. The crew had little option but to leave Syncom 4-3 in a “dormant” state in low-Earth orbit, although very soon the possibility of executing a repair on a later mission came to the fore. For Hoffman, who would go on to service the Hubble Space Telescope (HST) in December 1993, his first EVA was “an extraordinary opportunity.” At one point, he had little to do except gaze out at the Universe and the Home Planet and watch as the Sun peeked above the horizon to yield a new orbital morning. It was also a different experience for Dave Griggs. “He was a pilot,” said Hoffman, “but he had been assigned to fly as a Mission Specialist, so I think he was a little bit bummed-out.” Returning to the cabin, Griggs was forced to admit that, life as a Mission Specialist, on this occasion, was not all that bad.

By the time Mission 51D ended, its crew had earned for themselves the nickname “Swat Team.” Although the flyswatter had not succeeded in reviving Syncom 4-3, it had been an outstanding example of the NASA can-do spirit. “The flyswatter became the symbol of our flight,” said Rhea Seddon, “and when we got off the flight, we were handed flyswatters!” To this day, for his part, Walker still has in his possession a baseball cap, emblazoned with the legend: Bo’s Swat Team.

With the EVA behind them, their return home loomed on the horizon. During one of their final nights in orbit, Bobko called the crew onto the flight deck after dinner to simply float and watch the Home Planet drift by. Jeff Hoffman read a poem which had been written by his brother, a composer, whose verses reminisced on human tendencies for lofty thoughts and the possibilities of love, life, and freedom. His brother had given him the poem during his mountain-climbing days, and Hoffman now saw many analogies between flying in space and summiting the world’s highest peaks.

Re-entry on the 19th brought its own surprises for Hoffman, since he had exchanged seats with Seddon and was now sitting on the flight deck. “You’re surrounded by this red, then orange, then yellow, then white-hot plasma around the front windows,” he recalled, as Discovery knifed through the atmosphere, heading for the Kennedy Space Center (KSC) in Florida. “Behind you, there’s this flickering wave, just like the wake behind a motorboat, but it’s fiery and it’s just awe-inspiring.” After 10 minutes, the spectacle dimmed and Hoffman felt his weight returning. He could let go of a pencil and watch it gradually tumble, with the grace of a snowflake, toward the floor, faster and faster as he repeated the game in the lower atmosphere. As the shuttle headed across Florida, the four men on the flight deck could see the sprawling expanse of KSC. Touchdown on Runway 33 came at 8:54 a.m. EDT, five minutes shy of seven full days since leaving Pad 39A. However, a shock was in store.

Several months earlier, the crew had been assigned to Mission 41F, which was scheduled to perform the first “automated” shuttle landing, part of procedures for use in a contingency situation. They even created a mocking Latin motto for themselves: Vide, mater, sine manibus (“Look, Ma, no hands!”). To Bobko, autoland posed the added difficulty of having to define a “box” of performance during the final approach to the runway, whereby he could recover from the system in the event of a malfunction and still execute a safe manual touchdown. “The problem,” he recalled, “was to try and define how to recognize when the auto system was diverging and not let it get so far that I couldn’t take over and make a safe landing.” As a result, 41F had been scheduled to land on the vast dry lakebed at Edwards Air Force Base, Calif. A year later, with the preference loaded in favor of landing in Florida in order to avoid cross-country transport expenses, no one in NASA wanted to demonstrate autoland on the swamp-fringed Shuttle Landing Facility (SLF).



The flyswatter, attached to the end of Discovery’s Remote Manipulator System (RMS) mechanical arm. Photo Credit: NASA

As a result, it was decided that Bobko would land manually. Unfortunately, an eight-knot crosswind, gusting to 12 knots, required him to apply the right-hand brake and rudder more than the left to keep the vehicle on the centerline during the long rollout, and this “differential” braking caused the inboard right brake to “lock-up,” followed shortly thereafter by the outboard one. The result was a burst tire. In the words of fellow astronaut Mike Mullane, writing in his 2006 memoir, Riding Rockets, “it was a minor miracle that Discovery didn’t experience directional control problems … and careen off the runway.”

Don Williams remembered the incident vividly. “We’re down to maybe just about walking speed,” he said, “and there’s this big bang, thump, thump, thump, thump. I knew right away what it was; it was a blown tire. We’re almost stopped anyway, so it turned out not to be a big deal and not an issue. Of course, the only thing to worry about is, since this tire is blown, there could be some debris problems, which might cause a puncture or might cause some reason to have to evacuate, a fire or something like that.” On the middeck, Jeff Hoffman’s first thought was that one of the shuttle’s Reaction Control System (RCS) tanks had exploded. Charlie Walker wondered if they had run over an alligator!

The Capcom quickly radioed confirmation that someone from the runway landing crew had verified a tire blowout. “We didn’t think anything more about it,” Walker said, “until we got off the vehicle.” A member of the ground team told them about the blowout, that a trail of debris stretched some distance along the runway and that the astronauts would not be allowed to do their traditional walk-around of the vehicle, lest another of the fully-pressurized tires might blow and cause injury.

Despite the fruitless attempt to revive Syncom 4-3, the 51D crew could be justly proud of their accomplishments. Far from being disappointed, Rhea Seddon said years later, “we were really excited. We did everything we possibly could have done and we had pulled off all that stuff. If the motor had turned on, maybe we would have been five percent happier. But we were still pretty happy.” It did not detract from criticism, leveled at NASA from certain sections of the media, that another satellite had been lost.

None of the losses so far—TDRS-1 in April 1983, followed by Palapa-B2 and Westar-6 in February 1984 and now Syncom 4-3—were directly the fault of the reusable orbiter or her crews, but Flight International noted on 4 May that these incidents “focused attention on the shuttle deployment method.” Satellites carried by Europe’s Ariane expendable boosters, it was explained, were injected directly into Geostationary Transfer Orbit (GTO as part of the launch phase, whereas the shuttle required them to use two separate motors for GTO insertion, one at perigee and the other at apogee. Certainly, within days of the loss, and still riding the crest of a tremendous wave following the triumphant Palapa and Westar recoveries, NASA had already begun to focus its attention on a possible salvage mission, in the late summer of 1985.


Source: https://www.americaspace.com/2015/04/05/vide-mater-sine-manibus-30-years-since-shuttle-mission-51d-part-2/