Kosmos 154
A color drawing of a Zond L1 spacecraft
Mission typeOrbital test flight
Lunar flyby (failed)
OperatorSoviet space program
COSPAR ID1967-032A Edit this at Wikidata
SATCAT no.2745
Mission duration2 days
Spacecraft properties
SpacecraftZond L1P No.3
Spacecraft typeSoyuz 7K-L1P
Launch mass5375 kg [1]
Start of mission
Launch date8 April 1967, 09:07:00 GMT
Launch siteBaikonur 81/23
End of mission
DisposalLaunch failure
Decay date10 April 1967
Orbital parameters
Reference systemGeocentric[1]
RegimeHighly elliptical Earth
Periapsis altitude183 km
Apoapsis altitude223 km
Period88.5 minutes
Epoch8 April 1967
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Kosmos 155 →

Kosmos 154 (Russian: Космос 154 meaning Cosmos 154), also known as Zond No.3P, was a Soviet test spacecraft launched from the Baikonur aboard a Proton-K rocket. It was a prototype Soyuz 7K-L1 launched by Proton. It was an uncrewed precursor to the Zond series.[1]


The spacecraft was designed to launch a crew from the Earth to conduct a flyby of the Moon and return to Earth. The primary focus was a Soviet circumlunar flight, which help document the Moon, and also show Soviet power. The test ran from the Zond program from 1967-1970, which produced multiple failures in the 7K-L1's re-entry systems. The remaining 7K-L1s were scrapped, ultimately replaced by the Soyuz 7K-L3.[2]


Two test flights of the UR-500K/L1 system were performed in March and April 1967 under the designations Kosmos 146 and Kosmos 154. In April 1967, under the cover name Kosmos-154, the third model of the L-1 was placed into near-Earth orbit. Because of a control system failure that resulted in the premature jettisoning of the ullage motors, the main propulsion system of the Block-D did not ignite.[3] Kosmos 154 was one of the first Zond attempts. It was supposed to flyby the Moon but achieved Earth orbit only.[4]


Kosmos 154 was launched using a Proton-K carrier rocket, which flew from Site 81/23 at Baikonur. The launch occurred at 09:07 GMT on 8 April 1967. Kosmos 154 was operated in an Earth orbit, it had a perigee of 183 kilometres (114 mi), an apogee of 223 kilometres (139 mi), an inclination of 51.6° and an orbital period of 88.5 minutes. Kosmos 154 had a mass of 5,375 kilograms (11,850 lb).[1]

Kosmos 154 reached Earth orbit but the Blok D translunar injection stage failed to fire (ullage rockets, which had to fire to settle propellants in tanks before the main engine fired, were jettisoned prematurely). Kosmos 154 burned up two days later when orbit decayed, on 10 April 1967.[1]


  1. ^ a b c d e "Cosmos 154". nssdc.gsfc.nasa.gov. NASA. 27 February 2020. Retrieved 13 April 2020. Public Domain This article incorporates text from this source, which is in the public domain.
  2. ^ Brian Harvey (2007). Soviet and Russian Lunar Exploration. Springer Science & Business Media. p. 138. ISBN 9780387739762.
  3. ^ Sven Grahn; Bart Hendrickx (25 October 2017). "Kosmos 146 and Kosmos 154". Sven's Space Place. Retrieved 15 February 2018.
  4. ^ Robert Braeunig (3 November 2017). "Lunar Spacecraft (Unmanned)". Rocket and Space Technology. Retrieved 15 February 2018.