Beskrivning : An improved version of cargo freighters used to supply the Mir space station, the Progress M series had greater cargo capacity, a modernized approach/docking system and carried 2 solar panels to generate electrical power. Progress M can fly for 30 days independently and 108 days docked with Mir. Spare propellent in Progress M`s tanks can be transferred to Mir before it is consigned to burn up in reentry. In the past, extra fuel was abandoned with the craft.