In 1954, the design bureau headed by Pavel Tsybin started development of a ramjet-powered supersonic strategic bomber, the RS.
This design proved impracticable, and a smaller derivative, the 2RS was proposed, which would achieve intercontinental range by being air-launched from a modified Tupolev Tu-95 bomber.
[1] The RSR was primarily of aluminium construction, with a long circular-section fuselage, which housed a pressurized cabin for the pilot together with cameras and fuel, with thin, low-aspect-ratio trapezoidal wings.
[3] Based on the results of these trials, the RSR was redesigned (as the R-020) to make it more manoeuvrable at high altitude (it was proposed to carry out barrel rolls to avoid surface-to-air missiles).
Five R-020 airframes were virtually complete, only awaiting engines by April 1961, with another 10 planned, when Soviet Premier Nikita Khrushchev cancelled the program.