Space tugs

Fregat () is an upper stage developed by NPO Lavochkin for universal compatibility with a wide range of medium- and heavy-lift launch vehicles. Fregat has been used primarily with Soyuz and on a few occasions with Zenit rockets, and entered operational service in February 2000.

spacecraft vehicle designed to move the payload from a reference orbit to the target orbit, or direct it to an interplanetary trajectory

The Parom (ferry in Russian) is a space tug that has been proposed by RKK Energia. The purpose of this vehicle is to replace most of the Progress' active components. Progress spacecraft have flown re-supply missions since 1978. Nikolai Bryukhanov, RKK Energia's deputy general designer, said in May 2005 that the Federal Space Agency had received a design for a new space system. According to him, the system's operation principle is completely different from that used by Progress. A launch vehicle first places a Parom reusable inter-orbit "tug" into a 200 km orbit. As this spacecraft will no