Joe Allen (right, with red stripes on the legs of his suit) and Dale Gardner celebrate their success with a 'For Sale' sign, displayed high above Westar and Earth. The triumphant Mission 51A would cement the Shuttle's credentials as infallible…but it was an infallibility which would usher in a mistaken sense of complacency. The Shuttle, though capable of performing to near-perfection, was an imperfect machine. Photo Credit: NASA
Early in February 1984, astronaut Joe Allen was at the Kennedy Space Center, watching his former crewmate Vance Brand rocket into orbit aboard Challenger on Mission 41B. The pair had flown together on STS-5 and Allen later wrote in his bookEntering Space that he remembered thinking "as I wistfully watched the spaceship Challenger climb into the clear morning sky, that Vance had left without me". Allenhad been assigned to another Shuttle mission, but his own launch date and cargo remained in question. In September 1983, he was named to Mission 41G, along with fellow astronauts Rick Hauck, Dave Walker, Anna Fisher and Dale Gardner. Their initial task was to launch two communications satellites – SBS-4 for Satellite Business Systems and Telstar-3C for AT&T – and fly a unique astronomy platform called 'Spartan'. Two months later, in November, NASA reassigned the crew to 'Mission 41H' and instead assigned them either a classified Department of Defense payload or deployment of the second Tracking and Data Relay Satellite. The January 1984 manifest looked much the same, but by May Mission 41H (and with it Allen and his crew) had vanished entirely. Little could they have guessed that the mission they ended up flying would tie in with Brand's flight…and turn into one of NASA's most spectacular successes of the 1980s: the salvage of Westar and Palapa.
Westar-6 and Palapa-B2 were two large communications satellites, the first owned by Western Union and the second by the Indonesian government. When fully deployed in their operational 22,000-mile geostationary orbits, they each measured 22 feet tall by seven feet wide and took the form of enormous cylinders, coated with hundreds of solar cells. Westar ended up on the Shuttle as a result of a contract between Western Union and both NASA and the European Arianespace organisation. When an Ariane rocket was lost in a launch accident in 1982, one Westar had to be rescheduled and Western Union reconsidered its relationship with the Europeans and opted for the Shuttle instead. By March 1983, they had contracted with McDonnell Douglas to use one of its Payload Assist Module (PAM)-D boosters…and agreed to hold the aerospace giant "harmless" for any damage inflicted upon their satellite. Instead, Western Union received insurance from Lloyds of London to deal with any loss of assets. It was a significant decision.
Less than a year later, as Vance Brand and his 41B men settled into orbit, Westar-6 was spun-up and released from Challenger's payload bay. Fifteen minutes later, Brand and his pilot, Robert 'Hoot' Gibson, pulsed the orbiter's thrusters to move to a safe separation distance and at first it seemed that everything was going smoothly. The PAM-D engine appeared to ignite, beginning the boost of Westar to its correct orbit…but, all at once, extinguished itself. "It was in only a slightly higher orbit," wrote Joe Allen. "It was a long way from geostationary orbit; a terrible disappointment." Westar had been left in a lopsided orbit, with an apogee of about 650 miles and a perigee of just 160 miles. Sitting behind Westar in Challenger's payload bay – and now awaiting its own deployment – was Palapa-B2. Might it fall victim to the same fault?
Indonesia's Palapa-B2 departs the payload bay of Challenger in February 1984, attached to its PAM-D booster. Within minutes, calamity would strike in the same manner as it had struck Westar-6, and both satellites were left stranded in "unworkable" orbits. Photo Credit: NASA
A decision was taken to accept the risk. The Indonesian government concurred and Palapa was duly sent spinning into space. Unfortunately, the lightning of bad luck didstrike twice as Palapa's PAM-D fired, spluttered and died. The loss was a major disappointment, not just for Indonesia, but also for the member states of the Association of South-East Asian Nations, including the Philippines, Malaysia, Singapore, Thailand and Papua New Guinea, who would have used its services as a critical communications tool.
In the months and years which followed, the owners of both Westar and Palapa filed insurance claims – worth $180 million overall – although the former was dismissed because Western Union had already signed a disclaimer with McDonnell Douglas to cover PAM-D problems. The Indonesians, however, proceeded before a jury and the court agreed that a case of negligence could go ahead. Throughout the proceedings, evidence of possible poor design in the PAM-D was heard and Thiokol – the manufacturer of the rocket engine – was held ultimately liable.
Court proceedings were far into the future in February 1984, as NASA mulled over its Shuttle manifest, several of whose payloads were booked to ride PAM-Ds into orbit. "Preliminary investigation suggests that the solid-propellant motor stopped burning prematurely," Flight International explained on 18 February, "and that this may have been caused by the separation of the nozzle." It was suggested that sub-standard materials or components might have been to blame. Thankfully, the satellites themselves were healthy, although a plan to use Westar's own attitude thrusters to raise its orbit was described as "unworkable". NASA, however, had something up its sleeve. On Mission 41B, a unique jet-propelled backpack – the Manned Manoeuvring Unit (MMU) – had been test-flown and on Mission 41C had demonstrated its usefulness in recovering the Solar Max satellite. "The seed of an idea had been planted," wrote Joe Allen. "Could the dramatic debut of the MMU lead to the recovery of Palapa and Westar?"
As time went on, it seemed that the very crew to which Allen was assigned might receive the plum task. Rick Hauck had earlier described his mission as "a plain vanilla flight", but by March 1984 George Abbey – then-head of Flight Crew Operations – was looking specifically at them to attempt the salvage. "I think there were a number of things that worked in our favour," said Hauck in his NASA oral history. "One was just the timing of our mission. I had flown proximity operations on STS-7. Clearly, prox ops would be necessary to do this mission." The successful retrieval of Solar Max was another. Finally, the MMU, equipped with a Trunnion Pind Attachment Device (TPAD), offered yet more stimulus.
Dale Gardner participates in EVA training for the Palapa/Westar salvage operation. In addition to his space suit, Gardner wears a training version of the Manned Manoeuvring Unit (MMU). He and Joe Allen would be the last astronauts ever to fly the MMU in space. Photo Credit: NASA
However, there remained a problem. Some sort of mechanism was needed to actually snareWestar and Palapa and anchor them into the Shuttle's payload bay for the return to Earth. One morning, Dale Gardner arrived at work in a state of excitement. Years later, Hauck could not be sure if it was Gardner alone or in conjunction with the EVA equipment team which came with the idea, but the consensus was to build a probe-like 'stinger'. Measuring six feet long, it was called the Apogee Kick Motor Capture Device (ACD) and would attached to the arms of the MMU.
"The astronaut could then fly the stinger into the satellite's rocket nozzle," wrote Allen. "Once inside, he could release a lever that would allow toggle fingers to expand, much like opening an umbrella inside a chimney. A hand-driven crank would shorten the length of the stinger and pull the satellite against a padded ring at the stinger's base. The satellite would be held securely and the astronaut could then use the MMU's thrusters to stop its tumbling and hold it while the [Shuttle's Remote Manipulator System arm] grabbed a grapple fixture on the stinger." It seemed fairly straightforward, but for one thing: only the nozzle 'end' of the satellites could be clamped into the payload bay for the return to Earth; therefore, some other technique would be needed to temporarily 'hold' them in place whilst the stringer was detached and a cradle adaptor fitted.
NASA's solution was for an aluminium A-frame (properly termed the 'Antenna Bridge Structure') to be placed over the delicate antenna at the 'top' of each satellite. "Next, the arm would take hold of a grappling pin on the A-frame," concluded Allen, "keeping the satellite motionless while two astronauts manually fitted the adaptor at the nozzle end." With the adaptor in place, the RMS would lower the satellite into position in the bay and the spacewalkers would finally remove the A-frame. It was a brilliant plan and, if successful, promised to cement the Shuttle's credentials and vindicate its capabilities.
It also turned Rick Hauck's mission from 'vanilla' to chocolate…
Having already trained for EVAs on their respective first flights, it made sense for Allen and Gardner to be assigned to perform a pair of six-hour spacewalks to retrieve Palapa and Westar. Meanwhile, the other crew members of the flight – which the August 1984 manifest had by now redesignated 'Mission 51A' and scheduled for launch in early November – set to work in the simulators, refining rendezvous procedures. Hauck was joined on the flight deck by his pilot, Dave Walker, and flight engineer Anna Fisher. Their work together provided a breeding ground for some banter. During training for 'transatlantic aborts', simulating an engine failure, late in the ascent, that necessitated an emergency landing in North Africa, Walker would jokingly offer to trade Fisher for camels in exchange for the rest of them getting out. "Nowadays," Fisher told the NASA oral historian, "people would think that's probably not very politically correct. Then, Dave gave me this neat collection…of camels; all different kinds. These are guys who are trained in a different era. They were pilots in Vietnam. They saw all kinds of things. I'd gone to medical school. In histology class as they were doing their slide lectures, they would stick in Playboy centrefolds. It's just a way of breaking the ice."
Fisher's story is an interesting one, in that she became the first spacefarer to be assigned a mission within weeks of giving birth. Born Anna Lee Sims (the maiden name under which she would register for her astronaut interview in Houston in August 1977), her father was a military man and the family moved frequently, eventually settling in California, where she attended San Pedro High School. A lifelong interest in science and mathematics eventually inspired her to enter the University of California at Los Angeles to study chemistry, although by this time she had done voluntary work in Harbor General Hospital in Torrance and entered medical school. After her doctorate in 1976, she worked at Harbor General as an intern and later specialized in emergency medicine, practicing in Los Angeles. At around the same time, she became engaged to another young doctor, named Bill Fisher, and a mutual medical friend, Dr Mark Mecikalski, first saw NASA's astronaut advertisement and advised them both to apply for it. In the summer of 1977, a few days after Anna and Bill were married, she was summoned to Houston for her interview.
Rick Hauck (centre) and his crewmates on Mission 51A, knew by instinct and intellect that their task was far from simple or straightforward. Pictured here during training, Joe Allen can be seen behind Hauck's right shoulder, with fellow crew members Anna Fisher and Dave Walker at the right. Dale Gardner is obscured. Photo Credit: NASA
Both Fishers ultimately entered NASA; Anna in January 1978 and Bill in May 1980. Several years later, in the summer of 1983, she was pregnant with her first child and was surprised when they were both invited into George Abbey's office. "He said he wanted to assign me to a flight," she told the oral historian. "Did we have any reservations? I'm probably the only person who's been assigned to their flight about two weeks before they deliver!" Within six months of her daughter Kristen's arrival, Fisher was working feverishly, around-the-clock, to prepare for her first mission into orbit.
"Rick, Anna and Dave immediately began to log long hours in the Shuttle simulators in Houston," wrote Joe Allen, "practicing rendezvous procedures that would allow our ship, Discovery, to come within a few feet of each satellite without 'pluming' it out of reach with bursts…from the orbiter's [thrusters] or, even worse, causing it to tumble like a wildly gyrating top." There were other contingencies for which to prepare themselves. If Allen or Gardner experienced an MMU malfunction – a stuck-on nitrogen thruster, perhaps – it might be necessary to manoeuvre the Shuttle in order to perform a rescue. "Timing was critical," Hauck explained, "because orbital mechanics propagates differential velocities very quickly and I think we figured that ifthat were to happen and if he were to go off…if I didn't manoeuvre the Shuttle within 15 seconds and go after him, he was gone."
Two weeks after Discovery returned from Mission 41D, in early September 1984, NASA announced its plans for the salvage flight: Allen and Gardner had been certified as proficient with the MMU, recovery contracts had been signed with Palapa and Westar's insurance underwriters, equipment had passed vacuum-chamber tests and the crew and flight control team were comfortable with the intricacies of the rendezvous. Rick Hauck was livid. To him, the announcement that his crew would 'just' deploy two satellites and salvage two others did nothing but trivialise the mission; it made it sound easy. "If we get one of these satellites back," he told the NASA press affairs office, "it'll be amazing, and if we get both of them back, it'll be amiracle!"
In Hauck's mind, the space agency had shot itself in the foot by creating the illusion that Mission 51A would be a piece of cake, a walk in the park. "There's no sense in trying to tell the American people and the taxpayers that what you're doing is easy," he said, "because it isn't easy. Any implication that it's easy is a disservice to everybody." To Allen, it was another indication that it considered itself bulletproof. "NASA was still in its halcyon days," he told the oral historian, "still riding on the coat-tails of the successful Apollo missions, successful Skylab, successful Apollo-Soyuz, successful first tests of the orbiter." Hauck was right in his assertion that Mission 51A was far from simple. Yet the success that he and his crew achieved in November 1984 would further cement the flawed assumption that NASA was infallible…a sense of infallibility which would soon be torn apart.
The second part of this article will appear tomorrow.
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