The mission of this spacecraft was to land on the Venusian surface. The entry body contained a radio communication system, scientific instruments, electrical power sources, and medallions bearing the Coat of Arms of the Soviet Union.
The probe possibly crash-landed on Venus on March 1, 1966. However, its communications systems failed before it reached the planet.
Payloads are separated by bullets ( · ), launches by pipes ( | ). Manned flights are indicated in bold text. Uncatalogued launch failures are listed in italics. Payloads deployed from other spacecraft are denoted in brackets.