A Soyuz-TMA capsule is always attached to the ISS in "standby" mode, in case of emergencies. Operated in this configuration, the TMA has a lifespan of about 200 days before it has to be rotated out, due to the degradation of the hydrogen peroxide used for its reaction control system. Because of this limitation, the vehicle is planned for a typical six-month changeout cycle. The first flight of the TMA to the ISS occurred on October 29, 2002 with the flight of the Soyuz TMA-1.