Soyuz spacecraft, which serve as the station's emergency lifeboats, must be replaced every six months.

The coming mission is also one of the twice-yearly taxi flights that take up a fresh Soyuz craft to serve as the emergency lifeboat for the station.

Until now, the small craft had been held in reserve for use as an emergency lifeboat.

The portside emergency lifeboat had already been swung outboard and was lowered just before Olympic came to a halt.

The Soyuz, which serves as an emergency lifeboat, is replaced twice a year.

Paris suddenly realized he didn't know where the nearest emergency lifeboat was located"Got it!"

And one of these is that of emergency lifeboat.

The mission is one of the twice-yearly taxi flights, which bring up a fresh Soyuz to be the station's emergency lifeboat while returning another rescue craft.

The upper tier acts as an emergency lifeboat, sort of like the sub's evacuation system.

Probably a beam, though; this is one of their emergency lifeboats and they wouldn't want to destroy it unless they have to.