TOS - 1969 Credit - © Mark Wade

By 1969 the giant OS-1 space station had evolved to this configuration. Although pursued at least to the mock-up stage, all plans for orbiting the OS-1 had to be constantly deferred until the N1 booster proved itself. The termination of the N1 launch vehicle program ended any possibility of launching the station.

By 1969 the OS-1 had evolved to this configuration, as described in the official RKK history. In 1991 engineers from Energia and other design bureaus taught a course on "Russian Manned Space" at MIT. Among them was Dr. Vladimir Karrask, the first chief designer for the UR-500 (Proton), who told of a shroud he designed for the N-1. The shroud was cylindrical - 6 m diameter x 30 m long - with a very "Proton-like" blunt conical top. He indicated that it had flown on the N-1. Another engineer, S. K. Shaevich, stated that flight hardware (including a backup) was ready for the N-1 flights. There were those who believe that the last two N-1 flights had the Karrask shroud, and possibly the OS-1 station, mounted on them. It was not known if any OS-1 stations actually reached any stage of completion. All plans for the OS-1 had to be constantly deferred until the N1 booster proved itself. This did not prevent the design team from undertaking an even more grandiose study - the MKBS - in which OS-1 derived modules would form mere subunits of a huge space complex. At any rate the termination of the N-1 launch vehicle program ended any possibility of launching the station - unless it was the same as the Mir 2 jumbo space station that was planned for launch by the Energia booster in the 1990's.

Crew Size: 6. Length: 25.00 m (82.00 ft). Maximum Diameter: 6.00 m (19.60 ft). Habitable Volume: 510.00 m3. Mass: 75,000 kg (165,000 lb). Electrical System: 6 solar panels totalling 110 sq m.

• 1967 February 14 - Fairing for OS space station authorised. - Launch Vehicle: N1.
  Ministry of General Machine Building (MOM) Decree 'On construction of the N1 payload fairing by the Khrunichev Plant' was issued.