Twenty-five years have now passed since the International Space Year (ISY) in 1992, during which 29 national space agencies and 10 international organizations participated in various activities to promote the exploration of both the cosmos and our home planet, Earth. And although a pair of Russian cosmonauts—Aleksandr Volkov and Sergei Krikalev—were aboard the Mir space station on New Year’s Day, the first piloted launch of 1992 was a major venture in life and microgravity sciences, involving over 200 scientists and the respective space agencies of the United States, Germany, France, Canada, and Japan. Laden with the first International Microgravity Laboratory (IML-1), Shuttle Discovery’s STS-42 mission had gone through several changes in crew composition and had been shadowed by disappointment and tragedy in equal measure.
Originally, the IML series was to include three flights, utilizing the 23-foot-long (7-meter) Spacelab pressurized module in the shuttle’s payload bay, although IML-3 was later canceled and its payloads morphed into what became the Life and Microgravity Spacelab (LMS). The first mission, IML-1, was targeted for a May 1987 launch aboard Columbia at the time of the Challenger disaster. With the resumption of shuttle operations in the fall of 1988, efforts entered high gear for the mission to be launched in the spring of 1991. According to NASA’s March 1988 shuttle manifest, IML-1 would remain aboard Columbia, but its mission duration would be increased from seven to nine days, with the potential for a 10th day, dependent upon consumables expenditure.
The sensitive microgravity requirements of IML-1’s experiments required the shuttle to operate in a so-called “pseudo-gravity-gradient” orientation, with the tail directed Earthward, at a mean altitude of 160 miles (300 km). In the pre-Challenger era, the mission would enter a high-inclination 57-degree orbit, but this was later changed to 28.5 degrees and, ultimately, back to 57 degrees. The reason was associated with a shift in orbiters, as the shuttle manifest changed. With several flights extensively delayed by hydrogen leaks in the summer of 1990—and Columbia targeted to undergo a lengthy overhaul to install the Extended Duration Orbiter (EDO) capability—it became necessary to move STS-42 onto one of her sister ships. By February 1991, the mission had found its way onto Atlantis, with a projected launch in December of that year, but within weeks had shifted to Discovery and a revised date of February 1992.
“We moved from one orbiter to another orbiter to another orbiter,” remembered astronaut Bill Readdy, one of three STS-42 Mission Specialists, in a NASA oral history. “The silver lining for us, though, was originally, it was a due-east flight, 28.5-degree flight. As a result of going from Columbia—which was the queen of the fleet, the oldest and the heaviest—to Discovery, we were able to go to an inclined orbit of 57 degrees instead.
“If you think about what girdles the Earth, it’s pretty much water,” Readdy continued. “Right around the equator, plus or minus, there’s lots and lots and lots of water. You start to tip that a little bit, you go from 57 degrees North to 57 degrees South, every orbit, and you’re high enough that you’re seeing 1,500 miles (2,400 km) either direction. You’re seeing the upper part of Alaska, the Aleutian chain. South, you can kind of see the Antarctic. You’re going over New Zealand, Australia and well south into South Africa and Tierra del Fuego. From an Earth observation standpoint, it made the flight much, much more interesting. Of course, the down side was you’re supposed to spend most of your time in the laboratory, not looking out the window.”
To facilitate planning for a mission which was considered to be an early demonstration of research aboard Space Station Freedom, members of the IML-1 “science” crew were announced in advance of the “orbiter” crew … and a new astronaut designator was born. In June 1989, veteran astronauts Norm Thagard and Mary Cleave were named as Mission Specialists and a cadre of four international scientists—Canadians Ken Money and Roberta Bondar, Germany’s Ulf Merbold, and Roger Crouch of the United States—were selected to train for a pair of Payload Specialist positions.
Within months, however, the first changes took place. In late January 1990, NASA revealed that Cleave had resigned her position on the crew “for personal reasons” and she was replaced by another veteran astronaut, Navy flight surgeon Manley “Sonny” Carter. In her NASA oral history, many years later, Cleave recounted her reasoning. She had flown two previous shuttle missions, separated by almost four years, and with a PhD in environmental engineering she was shocked by the rate at which the Home Planet had changed. “Cities were grey smudges,” she remembered of the often depressing views of human impact. “The air looked dirtier, less trees, more roads.” She opted to relocate out of the Astronaut Office at the Johnson Space Center (JSC) in Houston, Texas, to work at NASA’s Goddard Space Flight Center in Greenbelt, Md., on robotic environmental projects.
Many of her colleagues advised her to remain in Houston, working in an engineering role for a year, in the hope that she would change her mind. “It was standard military practice,” Cleave said. “Don’t do any traumatic decisions until you think about it for a year.” She did not change her mind. In May 1991, she was named as deputy project manager for Goddard’s Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) mission, dedicated to studying the biological mass of the world’s oceans through detailed analysis of chlorophyll content and plankton production.
By the time Carter replaced Cleave on STS-42, two other major crew additions had been made. Firstly, on 2 January 1990, Commander Ron Grabe, Pilot Steve Oswald, and Mission Specialist Bill Readdy were assigned as the orbiter crew. The assignment of Oswald and Readdy was an interesting one, for both were “rookie” astronauts and both had previously been working on NASA’s proposed Long Duration Orbiter (LDO) capability. “The idea was to look at all the subsystems and the stowage on the orbiter and see if you could go 14 or 28 days with the existing Space Shuttle,” Readdy remembered. One morning, Chief Astronaut Dan Brandenstein called them over for a meeting in the Flight Crew Operations Directorate (FCOD) office. “They pushed this press release in front of us,” he continued, “and said ‘You have any problem with that?’ I had to read it three or four times, before I realized what it was. I saw Oswald’s name on there, but my name didn’t pop out.”
Readdy’s first reaction was to offer congratulations to Oswald.
Then came the real sweetener: “Well, buddy, you’re going, too!”
By the end of January 1990, with Cleave now replaced by Carter, NASA announced the creation of a new Mission Specialist position: that of “Payload Commander.” The agency retroactively named several astronauts, already in training for complex shuttle science missions, to the role, including Thagard on IML-1. It was revealed that the position would be “expected to serve as a foundation for the development of a Space Station mission commander concept” and that its purpose was “to provide long-range leadership in the development and planning of payload crew science activities.”
This responsibility encapsulated the development and co-ordination of training plans for the science crew, liaison with the Payload Operations Control Center (POCC) and principal investigators, attendance at relevant meetings and oversight of pertinent hardware and software changes. Thagard would thus be in charge of IML-1 and the organization of its science crew and would be responsible for the conduct and accomplishment of its scientific objectives. That said, the mission commander, Ron Grabe, would maintain authority for the overall safety and success of STS-42.
With the move from Columbia to Atlantis and finally Discovery, another issue of pertinence to Thagard arose. One of the reasons why Columbia had been assigned virtually all of the longer-duration Spacelab science missions was because, in the late 1980s and early 1990s, she was the only orbiter capable of housing as many as five cryogenic oxygen and hydrogen reactant tanks underneath her payload bay floor for the electricity-generating fuel cells. (At the time, Atlantis and Discovery accommodated four tanks apiece.) As shown in NASA manifests from the fall of 1990 and spring of 1991, the decision to move STS-42 onto Atlantis and, eventually, Discovery, forced a reduction in the duration of the flight to just seven days. In the words of Roberta Bondar, who was selected with Ulf Merbold for the two Payload Specialist posts, this change in duration—though not mission content—made the workload of the crew extremely fast-paced.
Yet there was tragedy to come. On the calm afternoon of 5 April 1991, Atlantic Southeast Airlines Flight 2311 was approaching Glynco Jetport—today’s Brunswick Golden Isles Airport—in Brunswick, Ga., after an hour-long flight from Atlanta. As the Embraer EMB 120 Brasilia aircraft approached the runway, in clear weather conditions, eyewitnesses noticed that it was flying at a much lower altitude than it should. At about 100-200 feet (30-60 meters), it suddenly rolled sharply to the left and crashed, nose-first, into trees. All 23 passengers and crew were killed. Among the dead were a pair of small children, former Texas Sen. John Tower … and STS-42 Mission Specialist Sonny Carter.
The accident was later determined to have arisen from a severe asymmetric thrust condition with the left-side engine’s propeller control unit, which caused a rapid loss of control. Events unfolded so rapidly that the pilots did not even have time to declare an emergency. For the Astronaut Office, Carter’s death was devastating, and not only because of STS-42. It was, in the words of fellow astronaut Mike Mullane, a “gross violation of the natural order.” Astronauts dying in aircraft accidents, Mullane wrote in his memoir, Riding Rockets, were meant to do so as pilots, not as passengers.
Two weeks later, veteran astronaut Dave Hilmers was named to replace Carter on the IML-1 mission. According to Don Puddy, then-head of Flight Crew Operations, it was a difficult decision and one he made with “regret.” When the STS-42 crew released their official patch, later in 1991, it included a single gold star, hanging serenely over Earth’s horizon, to honor the memory of “our crewmate, colleague and friend.”
Although Hilmers was not a scientist, but a Marine Corps engineer, he had long exhibited a fascination with life sciences and would go on to pursue a career in medicine after his departure from NASA in the fall of 1992. As a late addition to the STS-42 crew, Hilmers “never missed a beat,” according to Bill Readdy. “You couldn’t throw too much information at him,” he continued. “The guy’s just a sponge and able to absorb it all and then somehow figure out how to process it and spit it back at you.” Several of Hilmers’ fellow astronauts, including Rhea Seddon, remarked on his fascination with medicine and his desire to take an Advanced Cardiac Life Support Course. And in the words of Don Puddy, Hilmers was, quite simply, “a totally unselfish person.”
Operating around-the-clock on the IML-1 research experiments, the STS-42 crew was split into two shifts, designated “Red” and “Blue.” Grabe, Oswald, Thagard, and Bondar formed the Blue Team, with Readdy, Hilmers, and Merbold as their Red counterparts. “They tended to keep the Pilot and the Commander on the same shift,” said Readdy, “so that meant you had to have somebody else that was schooled in the orbiter systems and piloting tasks on the other shift.” That somebody, of course, was Readdy himself.
And on 22 January 1992—a quarter-century ago, this month—astronauts from the United States, Canada, and Germany set out for the launch pad to complete one of the shuttle program’s most complex research missions. Featuring more than 200 scientists from the United States, Germany, France, Canada, and Japan, IML-1 would truly lay the foundations for the research performed today aboard the International Space Station (ISS).
The second part of this article will appear tomorrow.