Salyut 7: Building a Worksite in Orbit

Transcripció

Salyut 7’s oxidizer delivery unit, or ODU, was part of the station’s propulsion system. Repairing its leaking plumbing became a carefully staged operation, because the equipment compartment was outside the station and had no nearby handholds. Progress 20 delivered twenty-five tools and other equipment. Its crew also attached a remotely extendable work platform with foot restraints. The worksite lay fifteen metres from the airlock, requiring the cosmonauts to carry roughly forty kilograms of equipment. On April twenty-third, Kizim and Solovyov drove anchor pins into the compartment’s outer skin, attached ladder and tool containers, and unfolded the ladder to five metres. On April twenty-sixth, they installed a television camera, then positioned themselves on the ladder and foot restraints. On April twenty-ninth, they installed the first bypass line between two fill tubes, but nitrogen testing still found a leak. On May fourth, they installed a second conduit, allowing the ruptured pipe’s location to be identified, though they lacked the tools to finish. After Progress 20 departed, the next crew delivered a Portable Pneumo Press, along with an instructional videotape, manuals, and photographs. Dzhanibekov trained with it on Earth, then trained Kizim and Solovyov aboard Salyut 7. During their eleventh EVA, on August eighth, they pulled back the thermal blankets and used the press to squeeze the stainless-steel pipe. Subsequent checks showed the ODU oxidizer system was finally sealed.