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Article Number: 11F91. Manufacturer's Designation: 7K-L1P. Class: Manned. Type: Lunar orbiter. Nation: USSR. Manufacturer: OKB-1.

First protoype version of the Soyuz 7K-L1 circumlunar craft. The L1P's had only boilerplate descent modules and were not capable of reentry and recovery.


Total Mass: 5,600 kg.

Soyuz 7K-L1P Chronology

01 January 1967 First L-1 Zond spacecraft mated to Proton Program: Lunar L1. Launch Vehicle: Proton 8K82K.

Fit tests at Tyuratam. Not launched (Interavia SD).

10 March 1967 Cosmos 146 Program: Lunar L1. Launch Site: Baikonur . Launch Vehicle: Proton 8K82K / 11S824. FAILURE: Stage 4 failed. Partial Failure. Mass: 5,017 kg. Perigee: 178 km. Apogee: 312 km. Inclination: 51.5 deg. Duration: 7.90 days.

Protoype Soyuz 7K-L1P launched by Proton into planned highly elliptical earth orbit. The first flight four-stage Proton rocket began assembly on 21 November 1966, with mechanical assembly completed by 29 November. Electrical connections and tests were completed by 4 December 1966. Due to New Year’s holidays work did not resume until 28 January 1967. By 28 February the fully assembled booster / spacecraft unit was completed in the MIK, including the 7K-L1P boilerplate spacecraft. The launch tower was added on 2 March 1967 and the system was declared ready for launch. A serious potential problem during preparations was the discovery that fuel gases could lead to pump cavitation at the turbine exits. Tests on the ground showed that the problem was not the fuel itself, but in the monitoring equipment. The launch vehicle and Block D stage functioned correctly and put the spacecraft into a translunar trajectory. The spacecraft was not aimed at the moon, did not have a heat shield for reentry, and no recovery of was planned or attempted. A successful launch that created false confidence just before the string of failures that would follow.

08 April 1967 Cosmos 154 Program: Lunar L1. Launch Site: Baikonur . Launch Vehicle: Proton 8K82K / 11S824. FAILURE: Block D. Mass: 5,020 kg. Perigee: 187 km. Apogee: 203 km. Inclination: 51.5 deg. Duration: 1.98 days.

Protoype Soyuz 7K-L1 manned circumlunar spacecraft. Reached earth orbit but Block D translunar injection stage failed to fire (ullage rockets, which had to fire to settle propellants in tanks before main engine fired, were jettisoned prematurely). Spacecraft burned up two days later when orbit decayed.


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Last update 12 March 2001.
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