When they entered the night side they closed the hatch and tried to dock with Skylab again, but this time the soft dock latches refused to lock. Kerwin says, “The three soft dock latches which had worked perfectly the first time simply wouldn’t capture. Pete tried and he tried and he tried and he tried again – we went through the back-up procedure and it looked like we had a spectacular failure here where we would have to come home because we couldn’t dock.
“We finally backed off a little bit and decided to try the last ditch third back-up procedure that was in the checklist, which fortunately one of our trainers had shown us a few weeks before launch. ‘We have never looked at this back-up procedure – why don’t we just go through it and show you where the wires are,’ he had said to us.
“This involved an IVA (Intravehicular Activity) so we had to get back into our suits, depressurise the spacecraft again, but this time we opened the tunnel hatch where the docking system was. We went up in there and cut a wire to bypass the soft dock system. We put the hatch back on but this time the deal was we were just going to force it in to where the main hard dock latches might work. In came Pete one more time, hosed on the fuel, pushed the switch to activate the twelve main latches and we counted one, two, three; we got to about seven and we heard this rat-a-tat sound which was all the twelve latches locking on one after the other – that was a very sweet sound – and we had a good hard dock. We had been up for about eighteen hours by then – we were kinda tired – so we had a snack and went right to bed.”
When Conrad, Weitz, and Kerwin awoke, the first task was to check the atmosphere in the laboratory for any deadly gases. Weitz says, “We had a sniffer – a glass cylinder with a rubber bulb on one end like a hygrometer they used to test batteries in the old days – with an adapter to go in the MDA hatch. We sniffed that and it didn’t show anything so we opened the hatch. In the MDA it was relatively cool, in the fifties (10°C) as I remember, but when we got in the airlock it was very hot. Pete and I said if it’s hot in there we’ll go in our skivvies, but then we soon found out why the people in central Africa wear a lot of clothes when they are in very hot conditions – we bundled up rather than took clothes off because of the heat. We made forays into the workshop for about ten or fifteen minutes until we felt we needed a break then we went back to the MDA to cool off for a while. Except for the temperature, everything looked as it should be.”
Kerwin remembers, “In the lab it was quite warm and it had a somewhat chemical smell – not bad – a sort of gasoline smell.” The temperature was 54°C, but the humidity was so low they were able keep working for up to five hours at a time.
The next item was the thermal shield. Conrad and Weitz carefully eased the $75,000 parasol developed by Kinzler and his gang through the scientific airlock and extended the struts until the sunshield was in place. Weitz says, “On day two we went to work putting up the parasol. It took most of the day. As I remember everything went according to plan but as it turned out all the four extendible booms didn’t extend, one of them did not, so the thing was not quite a rectangle, but we didn’t know that at the time.”
Conrad set the scene at the time. “The rod extension has gone easily enough. It’s pretty warm down here, so we are taking little heat breaks.” Almost immediately the temperature in the laboratory began to drop, eventually taking a week to stabilise at 21°C.
Weitz adds, “The next day things had cooled down a little so we started the activation procedures which meant moving a lot of stuff. A lot of items were bolted to the triangle floor.”
Now came the most difficult job – extending the remaining solar array. The solar panel beam was extended by a hydraulic piston. This beam was jammed by a strap from the micrometeorite shield lodged there during the launch phase. On the ground at the Marshall Space Flight Center astronauts Rusty Schweickart and Story Musgrave had developed and practiced the procedures to clear the beam on a mockup of the laboratory, complete with the strap, as seen on the television pictures sent by Conrad.
Fourteen days after the first docking, Conrad and Kerwin tackled the procedures developed by Rusty Schweickart. Working on the smooth tank-like laboratory with no gravity, toe or handholds to steady them, the two astronauts set up the long-handled cutter, like pruning shears, used in the first attempt. They had to wait and fly through an orbital night before they could try it out.