Skylab 4, the last expedition to America’s first space station, lifted off on November 16, 1973, with Gerald P. Carr, Edward G. Gibson and William K. Pogue on board. It was the first flight for all three crewmen. Their launch had previously been delayed for five days due to problems with the six-year old booster. First, engineers found hairline cracks in the fins on the first stage, which had been manufactured in 1967. They replaced all eight fins. Next, technicians discovered similar cracks in the structure that connected the rocket’s two stages. They added aluminum plates to the structural beams to reinforce them. The final booster problem came after a practice fueling, when two of the fuel tanks buckled slightly as fuel was being drained. Refueling the tanks under pressure forced the dome-shaped tops of the tanks back into shape and the Saturn IB was pronounced ready for flight.
Officially, the flight was planned to last 56 days, but mission managers left the option open for a much longer flight – up to 84 days. When Carr, Gibson, and Pogue blasted off, they carried supplies and equipment in the Apollo Command Module (CM) for an extended space flight. Included was 160 pounds of additional food. Mission planners found the quantity of additional food required due to the flight extension exceeded the storage capability of the CM. The solution was to supply the astronauts with high-density food bars that they ate every third day. The bars provided enough calories, but did not satisfy the astronaut’s appetites, so they felt hungry every few days. The Skylab 4 crew also found they became hungry sooner following a meal than they usually did on earth.
Seven hours after launch, Skylab 4 reached the orbiting station. “She looks pretty as a picture,” reported Carr. When the astronauts gently nudged the CM docking probe into the port on the MDA, they could not get a hard dock, or “capture.” Another attempt failed. Finally, on the third try, Skylab 4 docked with the station.
The previous crew reported some problems adjusting to weightlessness — what is now called “space adaptation syndrome.” Symptoms include nausea, vomiting, disorientation, and general malaise. The entire Skylab 3 crew of Alan Bean, Owen Garriott, and Jack Lousma were affected, with Lousma being the worst. By the end of the second day, they were a full day behind schedule because of their incapacitation. It took three days for them to get over their problems.
Individual astronauts on Apollo flights had similar problems with motion sickness, but never an entire crew. Mission managers and physicians were very concerned, and prescribed some preventive measures for Skylab 4. All three astronauts were supposed to take anti-nausea pills as soon as they reached space. NASA doctors also told them to avoid unnecessary head movements. The astronauts were further directed to spend their first night in space in the CM, because the doctors thought moving into a large open area too soon would exacerbate any symptoms. Carr, Gibson, and Pogue thought the doctors were overly cautious, and were guessing, at best.
Carr and Gibson took their anti-nausea pills as directed, but Pogue, who had been a member of the U. S. Air Force Thunderbirds before becoming an astronaut, had not. He had a reputation of having an “iron stomach” because of his resistance to motion sickness, but space was another matter. Pogue took his medication a few hours into the flight, but it was too late. Shortly after docking with the orbiting laboratory, he vomited. The astronauts feared the ground based doctors might overreact to Carr’s distress.
Carr and Gibson discussed the situation and decided to not report that Pogue vomited; a clear violation of mission rules. Instead, they’d state only that he’d been nauseated. Unknown to them, there was a tape recorder running, on communications “Channel B.” Every night the Channel B tape was automatically downloaded to Mission Control and transcribed. Everything they said concerning the episode was recorded and later broadcast to Houston.
The next day, Pogue felt somewhat better, and the crew began the process of activating Skylab. By mid-afternoon, the previous day’s Channel B transcript had made its way through NASA, where it created an uproar within senior management. Alan Shepard, chief of the Astronaut Office, came on the air and told the crew: “I just wanted to tell you, that on the matter of your status reports, we think you made a fairly serious error in judgment here in the report of your condition.” Carr accepted the reprimand and said “…it was a dumb decision.”
By the end of their first day aboard Skylab, they began to encounter other problems as well. Many tasks required to activate the station took longer than expected, and the astronauts soon fell behind in their mission timeline. Compounding the situation, the previous crew had exceeded their objectives, so expectations for Carr, Gibson, and Pogue were very high. Mission Control expected the Skylab 4 crew to pick right up, at the same pace, where the last crew left off.
On a mission such as Skylab, scientists on the ground who devised the experiments to be performed in space — so called “Principal Investigators” — were eager to get as much data as possible. To maximize the return, every minute of the astronauts’ days were planned. This became particularly important with the decision to extend the last flight to 84 days. NASA’s budget was under severe scrutiny after Apollo, and each day the astronauts remained in orbit cost the space agency an estimated half million dollars. The scientific return from the extra days had to be sufficient to justify the extra expense. Carr, Gibson, and Pogue soon discovered that Mission Control had not even allowed adequate time for them to move from one work location to another, much less provide time to set up or put away equipment in the weightless environment.
As their fourth day in the workshop ended, Carr told Mission Control some tasks had to be removed from the next day’s flight plan “If we’re ever going to get caught up.” The crew hadn’t had time to properly stow all their equipment and Skylab was “…really getting to be a mess.”
Pogue and Gibson performed a 6 1/2-hour extravehicular activity (EVA) on November 22 to try to repair an inoperative Earth resources sensor antenna and reload the ATM cameras. Working together, they restored half the antenna’s function. It was a microwave antenna that was supposed to scan both fore and aft and side to side. The astronauts determined the pitch (fore and aft) circuit was at fault, and could only restore the antenna’s side to side motion. Still, this delighted the Principal Investigators, because they could obtain almost all the desired data with this partial repair.
Houston gave the astronauts a day off on November 24, and allowed that flight planners had underestimated the length of time it took to perform many tasks. This welcome respite gave the crew a chance to catch up on their schedule. In his review of the astronauts’ first week in space, Carr described the pace as “frantic,” and told Mission Control (via the Channel B recorder) of their frustration over not being able to keep up with the timeline.
Early in their third week in space, one of the control moment gyros (CMGs) used to orient the station overheated and slowed down. Ground controllers turned off the CMG, which left Skylab with two functioning units. What made the situation acute was that the station was low on maneuvering gas for the attitude control thrusters. All the maneuvers needed to control temperatures inside the OWS after it first reached orbit had seriously depleted the initial supply. With one CMG gone, greater reliance was going to be placed on the maneuvering thrusters to orient the station. At first, it looked as though there might not be enough propellant for the entire mission. Some experiments, such as observations of the earth and the comet Kohoutek, required complex and precise orientation maneuvers. Houston had to work out the most efficient maneuvers possible and radio revised instructions to the crew to keep the mission going.
Czechoslovakian astronomer Lubos Kohoutek spotted a particularly bright comet that was named in his honor on March 7, 1973. As the year drew to a close, excitement mounted about “the comet of the century.” Comet Kohoutek, it was predicted, would be even more spectacular than Halley’s Comet had been in 1910. And, for the first time, there would be a team of astronauts equipped with a powerful array of telescopes in orbit to view the comet. As it turned out, Comet Kohoutek was not nearly as bright as predicted and people on the ground were disappointed by its lack of visibility. In sharp contrast to those on Earth, Carr, Gibson, and Pogue had a good view of the comet and made detailed observations of it using the ATM. On Christmas day, Carr and Pogue performed an EVA to change film cassettes in the ATM and photograph Comet Kohoutek.
To celebrate Christmas, the astronauts fashioned a “tree” out of the metal “spines” used to hold food cans in their storage canisters. Unknown to them, a fabric tree had been stowed onboard the station along with small gifts from their families. On Christmas morning, they were told where to find their surprise packages.
By Christmas, they had been in space for over a month. When they passed the 30-day mark, NASA officials gave them the go ahead for a 60-day mission that was “open-ended to 84.” In theory, the mission would be extended week by week, but few people doubted it would go on for 84 days.
Problems persisted with scheduling, however, and reporters began asking how the Skylab 4 crew compared to earlier ones. A perception emerged that the astronauts were slower, more prone to mistakes, and weren’t as productive as their predecessors. Senior NASA managers quickly defended the crew, and reporters seemed to let the matter drop. But, complaints from space continued; Carr pointed out that they wouldn’t “be expected to work a 16-hour day for 85 days on the ground, so I really don’t see why we should even try to do it up here.”
Gibson described the time they’d been in space as a “33-day fire drill” and told Mission Control that he was going to take whatever time was necessary to properly conduct individual experiments. He and his fellow crewmembers felt that flight planners had over scheduled them, being more concerned by the quantity of data produced rather than its quality. Things came to a head on December 28, when all work was set aside while Carr, Gibson, and Pogue held a frank discussion with Mission Control. The discussion took 55 minutes and gave both parties a chance to air their concerns and grievances. One of the results of the discussion (which took place over an open channel) was that the astronauts would have greater flexibility in scheduling and performing tasks. With that change, flight controllers noted an almost immediate improvement in the astronauts’ morale.
Most of the perceived lack of performance by the Skylab 4 turned out to be erroneous, anyway. When mission managers compared the performance of the second and third Skylab crews between the 15th and 30th mission days, they found no significant difference in work output. In fact, by the end of the flight, Carr, Gibson, and Pogue had completed 39 Earth survey passes versus a planned 30 and used two complete sets of solar instrument film when only one set had been planned.
One of the high points in the flight came on January 21, 1974, when Gibson caught a medium-size solar flare with the ATM instruments. This was the first time a flare had been recorded from beginning to end with spaceborne instruments. It was a tribute to Gibson’s patience and perseverance. Gibson spent many hours at the ATM console hoping to observe such an unpredictable event.
The Skylab 4 crew returned to Earth on February 8, 1974, after a marathon 84 days in space. They splashed down in the Pacific Ocean, about 180 miles southwest of San Diego and were quickly taken aboard the helicopter carrier USS New Orleans. Doctors were surprised to find the trio in better physical condition than previous crews. The astronauts also readjusted more quickly to the Earth’s gravity than earlier Skylab crewmembers. This was attributed to their having spent more time exercising than the Skylab 2 or 3 crews.