A Soyuz craft is pictured docked to the Mir space station during the Shuttle-Mir program. Photo: NASA

Russian space managers have changed the makeup of a two-man cosmonaut crew on standby for a flight to the abandoned Mir space station in the event of any future emergency that might cause an uncontrolled re-entry.

Commander Salizhan Sharipov and flight engineer Pavel Vinogradov had been in training for a potential flight to Mir, which is scheduled to be deorbited in late February, but they have been replaced, NASA sources said today.

The ITAR-TASS news agency reported Tuesday the new crew is made up of commander Gennady Padalka, a Mir veteran, and flight engineer Nikolai Budarin, a Mir veteran who also flew aboard NASA's space shuttle.

A NASA source confirmed the crew change, but could not confirm the identities of the replacements.

But Padalka and Budarin trained extensively for a potential emergency flight to the international space station last year in case the Russian command module, Zvezda, was unable to dock with the outpost.

Zvezda and the space station made a normal linkup, however, and an emergency flight was not necessary. But given their previous training, Padalka and Budarin would appear to be well suited for any emergency flight to Mir.

No such flight to Mir is currently planned. The Russians plan to launch an unmanned Progress supply ship to Mir around Jan. 10. The Progress will be used to raise Mir's orbit slightly, setting up a controlled re-entry around Feb. 28.

But an emergency crew might be needed if major problems develop between now and then.

While the Russians have not announced an official reason for the crew swap, Sharipov told ITAR-TASS he was upset by the decision.

"We had been training for more than six months to act in emergencies," he told the news agency. "Everything was all right, but the (governmental) commission decided to change the crew."