MOSCOW, Oct 1: The Russian-American crew on the ageing space station Mir began dismantling a troublesome computer today and the team on the US Space shuttle Atlantis slept before a planned five-hour spacewalk.Russian cosmonaut Vladimir Titov and US astronaut Scott Parazynski are due to step outside Atlantis at 1844 GMT on the first US-Russian spacewalk from the shuttle, which is docked with Mir.Their mission is to retrieve two American science experiments placed on Mir's exterior in 1995. They will also store outside Mir a specially designed cap which could be used later to plug a leak in the Spektr module, damaged in a collision on June 25.A spokeswoman at mission control outside Moscow said the Atlantis crew would wake only at 1130 GMT. But the crew on Mir had already started dismantling a computer which has broken down repeatedly and is needed to keep Mir aligned to the sun.``The crew started dismantling the computer today and hope to have the new one up and running by tomorrow or Friday,'' the spokeswoman said by telephone.``Everything is going according to plan. The cosmonauts are in a very good mood.''The June collision, in which the Spektr scientific module was punctured, was the worst in Mir's 11-year history.Mishaps since then have included computer breakdowns which several times left Mir spinning out of orientation with the sun, which it must face to gather maximum solar energy.Without the computer, Mir's solar panels cannot be held in line with the sun and work less efficiently. The space station is now being kept aligned by Atlantis' engines - standard practice during six previous Mir-shuttle dockings.The June collision, and other problems this year including an onboard fire and difficulties with the oxygen and power supplies, have raised doubts about US involvement in Mir.But Russian President Boris Yeltsin expressed confidence in the orbiting space laboratory yesterday and accepted a commission's finding that human error was not primarily to blame for the collision.Yeltsin appeared to backtrack on comments several weeks ago in which he blamed the crew for the accident.US space officials shrugged off doubts about Mir's safety by giving the go-ahead last week for 41-year-old medical doctor and engineer David Wolf to replace British-born NASA physicist Michael Foale in Mir's three-man crew.Atlantis docked with Mir on Saturday. During today's five-hour spacewalk, Titov and Parazynski will not try to fix the hole in Spektr.But they will strap a 78.5 cm cone-shaped cap to the outside of Mir's docking module for future use. It is too large to fit through Mir's hatches.
