Following the failed docking of Soyuz 15, it was decided that the Igla docking system needed significant modifications. Due to the amount of time needed to make the changes, and the limited time Salyut 3 had left in orbit due to orbital decay, the next planned mission to the station was cancelled. The spacecraft which would have been used on the third mission to Salyut 3 was later used for the mission Soyuz 20 to Salyut 4 (a civilian space station).