Unmanned long-duration test of Soyuz spacecraft.
Docked with Salyut 4.
LIFTOFF
launched from Pad 1/5 · Baikonur
aboard Soyuz U · into LEO
Soyuz 7K-T/A9 Soyuz 20
docked at Salyut 4
returned to Earth Feb 16, 1976