The second generation of the Soyuz spacecraft, the Soyuz Ferry or Soyuz 7K-T, comprised Soyuz 12 through Soyuz 40 (1973-1981). In the wake of the Soyuz 11 tragedy, the spacecraft was redesigned to accommodate two cosmonauts who would wear pressure suits at all times during launch, docking, undocking, and reentry. The place of the third cosmonaut was taken by extra life-support systems. Finally, the 7K-T, being intended purely as a space station ferry, had no solar panels, instead sporting two large whip antennas in their place. As a result, it relied on batteries which only provided enough power for two days of standalone flight. The idea was that the Soyuz would recharge while docked with a Salyut space station, but in the event of a docking or other mission failure (which ended up happen