Highways Into Space: A first-hand account of the beginnings of the human space program (41 page)

We also had an opportunity to participate in an international event and call attention to the progress being made in ASTP. By mutual agreement in the PAO subgroup during December 1972, the two sides committed to build a full-scale mockup of the Apollo-Soyuz docked together. The purpose was to demonstrate the progress on ASTP by displaying this mockup at the May1973 Paris Air show. This turned out to be an excellent opportunity to focus attention on the project and its launch in 1975. Chuck Biggs, of the MSC PAO Office, was the point man for all of the arrangements for building the mockup and its display at the Air Show. Rockwell volunteered to build the mockup. And although we were late in identifying this possibility, the Air Show organization responded graciously and constructively, making room for the display with the mockup by co-opting some of the parking lot. It was heralded by some in the press as “the focal point for the Thirtieth Paris Air Show.” The Apollo-Soyuz was on display on May twenty-fifth to June third, 1973.

There was another key player in this venture. Larry Griffin, twin brother of Gerry Griffin, was active duty Air Force back from his tour as a forward observer pilot in Vietnam. Since the Air Force was beginning to prepare for their role in Shuttle operations, Larry Griffin was assigned to my office to help transition experience from NASA and JSC program operations. Larry had a great flying experience base to help with the 747 transport of the model from California to Paris. The trip even included a “show the flag, low altitude pass” over the city of Paris. You might wonder how I liked the Air Show. Well, I never saw it. The rest of my job, in the form of Skylab, claimed its rightful attention. The Skylab flight schedule began in May 1973 and the last of the manned visits landed in February 1974. This flight period contained some very tense weeks and it coincided with critical milestones in a busy ASTP year.

I was at KSC for the launch of the Skylab workshop, our first U.S. Space Station. This launch was to be followed on the next day by the first crew, commanded by Pete Conrad with Paul (PJ) Weitz and Dr. Joe Kerwin. The launch was beautiful and awe-inspiring as they always are.

The pre-programmed commands from the SIB Instrument Unit began the process of waking up the workshop’s systems. One radiator cover away, four sections of the payload shroud away and the rotation of the telescope from forward to the side of the docking adapter readied the Skylab to receive our CSM on the nose of the assembly. In thirty minutes or so, the ship started to give out the early signals of distress. The solar arrays and the meteoroid shield both had erratic and confusing telemetry indications. One indicated a partial deployment, and another that both solar wings were not still attached. Don Puddy’s team in MCC anticipated that there were at least two problems. The possibility that both solar panels had failed would cut the onboard power drastically. The ATM arrays also provided five kilowatts. And, the loss of the micrometeoroid shield would fairly quickly result in high heating on the sun side. (Normally, the vehicle flies in the solar inertial mode where one side of the structure is always pointed towards the sun.) An unexpected indication from an accelerometer at the time of maximum dynamic pressure was found in a post launch data review. This suggested a failure of some part of the structure. Soon enough, temperatures on the external structure started to rise. Without a fix and in the same attitude, internal temps were calculated to reach seventy-seven degrees Celsius (one hundred forty degrees Fahrenheit) and one hundred sixty-five Celsius (two hundred ninety-three degrees Fahrenheit) on the outer skin. Some of the rate gyros were not averaging as they should and caused excessive usage of the nitrogen gas. It was decided to delay the crew launch by five days.

The heating and projected internal temperatures were the dominant problem for the operations team, with the HOSC fully engaged and contributing. The MCC flight control team did a great job of improvising around the bad data from the rate gyroscopes. They used the power received by the solar panel to estimate pitch up from the solar inertial and skin temps on the opposite sides to judge the roll. Calculation of momentum let them approximate yaw. They had to get the vehicle out of full solar inertial and find an attitude that provided sufficient power but was better for reducing internal temperatures. A pitch up attitude of about forty-five degrees seemed to be the best compromise; it was enough power to charge the batteries to get through the next night pass and stabilized the internal peak temperatures forty-two degrees Celsius (one hundred eight degrees Fahrenheit). There was work for everybody. How did the heat affect the rest of the provisions onboard? What should be resupplied? How to shade the ship? How to get more power? We had other subjects to address back in Houston, like the stowage in the CM for the rescue trip in a matter of days.

I remember George Merrick, of Rockwell, and Chet Lee being on the plane ride back to Houston after launch. We were all relatively unfamiliar with Skylab, but knew that there were two airlocks for exposing experiments, on the solar side and the anti-solar side of the ship. This seemed like a gift from above for the heating problem. Why not devise an umbrella of sorts that could be stored in one of the airlock boxes and extended into space to provide shade? The more we talked about it the better it sounded. When we got back to Houston, people had already thought of it but the frontrunner candidate was a standup EVA in the CSM open hatch and a wand-type device to attach it somewhere to the external structure. There were several good candidates and at least two came right down to the wire. At MSC, Jack Kinsler, of parachute competence, and Don Arabian, of getting-it-done competence, prevailed and so did the parasol. The box was about four feet long and about eight to nine inches on a side. It was this box and the many other new tools stowed under the couches that gave the CSM team and me a fit in trying to stay within the allowable center of gravity limits for safe uprighting of the capsule in an abort. And then we had to work at expanding those limits. Rusty Schweikart did a great job of representing the crew and prepping them for the parasol deployment.

Skylab Cutaway View

SL 1 Workshop launch

Pete, PJ and Joe lifted off on May twenty-fifth, ten days late and loaded for an exciting trip. The probe and drogue docking took five attempts. We were getting a message that it was time to move to a new design. Most of my mission – following time was spent in the Mission Evaluation Room (MER). It was gratifying to see problem solving from that end of our system. The flight control team, the new Flight Directors and the HOSC team were impressive in how they handled this near-Apollo-XIII start to our new space station.

Skylab 2 Off the “Milkstool” on Pad

Parasol in Work

When the crew arrived at Skylab, they flew a planned external inspection of the whole lab. Pete reported, “Solar wing 2 is gone, it’s off the bird” and, “Solar wing 1 is partially deployed, there is a bulge of meteoroid shield under it in the middle, and holding it down,” and “the air lock is free of debris.” When the inspection fly-around was completed, Conrad was optimistic that they could clear the solar array wing from the hatch in standup EVA. Weitz stood up in the hatch, while Kerwin held on to him, and Conrad piloted the CSM. They just could not pull the solar array up, it was being held by the strap from the meteoroid shield. By mid-afternoon on the May twenty-sixth, the crew was in the workshop and it was warm enough to force them to the cooler docking adaptor module occasionally.

The parasol went out according to plan and when it was first deployed, Conrad reported that it was only covering two-thirds of the intended area. The ground was confident that as the material warmed up that it would gradually extend and cover what it was planned for. By the twenty-ninth, the cooling down was proceeding and the Huntsville engineers calculated that it would soon stabilize at twenty-six degrees Celsius, about eighty degrees Fahrenheit. The crew then went into actively performing their major experiments – medical tests, solar observations and preparations for earth resources tasks. One of the earth resources experiments involved decreasing the sunlight on the solar panels and going to batteries for the extent of the pass. Four batteries dropped off-line and the flight controllers were only able to restore three of the four. One battery is worth two hundred fifty watts.

Skylab 2 in Flight After Workshop Repair

The next major activity was to start on the plan to clear and erect the solar array panel; the crew rehearsed all this inside the workshop with Kerwin in a suit. Again, voice communications with MCC aided by TV coverage confirmed that the crew was ready to try freeing the solar array. The geometry on the outside can be thought of with the parasol being at the top of the workshop. The solar array wing was ninety degrees from the airlock that the parasol was deployed at. At first, Kerwin had a lot of trouble because he just couldn’t restrain himself to one position and he was having trouble getting the cutter on the strap that was holding the solar wing down and against the fuselage. Kerwin discovered if he shortened his space suit tether he was able to get the cutter device in place and cut the strap. Kerwin and Conrad went to pull the solar array wing up and very soon it just popped up and it was now in place, looking fine to the crew. This restored about twenty-five percent of the total original power in the workshop.