Unlike Russia's Mir station, ISS gyroscopes are located outside the station on the US Unity module's external metal girder; that's why the crew must perform a space walk in order to repair them, he explained.
The ninth long-duration ISS expedition is to perform two space walks in line with mission plans.
It's hard to say whether the gyroscope will be repaired by Gennady Padalka's crew because the situation is not critical, RIA Novosti's interlocutor stressed.
For his own part, a NASA spokesman told RIA Novosti that the entire gyroscope didn't have to be replaced. The gyroscope's power-supply unit must be replaced. That unit will be taken from another gyroscope, which had stopped operating more than a year ago, he noted.
Only two out of the station's four US-made gyroscopes are currently functioning without a hitch. Meanwhile the ISS orbit will be adjusted with the help of Russian-made attitude-control engines, which are installed on the Russian module, and which fire a lot of fuel.
