LAST HOUR

As the mission entered its final hour, one chore for the astronaut in the right couch was to install a 16-millimetre movie camera in a bracket next to his rendezvous window. This would record the view from the window looking backwards along their glowing wake. The camera did not have a direct line of sight, but rather was mounted off to one side and used a small 45-degree mirror to see out.

In the meantime, a final few items were stowed away for the re-entry. These included the ORDbAL box, the COAS optical sight, the chlorine injector and gas separator of the water squirt gun. An important aspect of stowage for re-entry was to ensure that objects were not only well secured but that their weight, soon to rise more than six times their earthly weight, and their edges and points, did not strike a crew member or cause damage, especially to the aft hull. Additionally, items above the crew had to withstand the sudden shock of the spacecraft’s impact with the ocean’s surface.

With 50 minutes to go, tasks leading up to their meeting with entry interface were coming thick and fast. The heaters that were preheating the CM thrusters were switched off, and a check was made of the two batteries that would fire the pyrotechnic devices. These were separate from the spacecraft’s three main batteries.

If either battery indicated less than 35 volts, extra energy was taken from the main supply to ensure operation. The third of the CM’s other three batteries was connected across both of the main power busses. The batteries would become the spacecraft’s primary electricity supply after the fuel cells were cut adrift with the service module.

Л check was made to see that their backup attitude reference, the GDC. was not drifting excessively. If it was, then two instruments that were relying on its output had to be treated as suspect: the right-hand FDAI and the RSI, the latter being the instrument that showed the direction of their lift vector and therefore a key item on a manual re-entry.