Luna 10 / E-6S Credit - NASA

The E-6LS was a radio-equipped version of the E-6 used to test tracking and communications networks for the Soviet manned lunar program. Otherwise the spacecraft instrumentation was similar to that of the E-6LF and provided data for studies of the interaction of the earth and lunar masses, the lunar gravitational field, the propagation and stability of radio communications to the spacecraft at different orbital positions, solar charged particles and cosmic rays, and the motion of the Moon.

Typical orbit: 350 km x 60637 km at 52 degrees inclination. Mass: 1,700 kg (3,700 lb). Main Engine: KTDU-5A.

• 1967 May 16 - Cosmos 159 - Program: Lunar L1. Flight: Soyuz 7K-L1 mission 1. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 4,490 kg (9,890 lb). Perigee: 350 km (210 mi). Apogee: 60,637 km (37,678 mi). Inclination: 51.60 deg. Period: 1,174.20 min.
  The E-6LS was a radio-equipped version of the E-6 used to test tracking and communications networks for the Soviet manned lunar program. The payload entered the desired orbit as Kosmos-159.

• 1968 February 7 - E-6LS s/n 112 - Program: Lunar L1. Flight: Soyuz 7K-L1 mission 1. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. FAILURE: At T+524.6 sec Stage 3's engine 11D55 cut off prematurely because it ran out of fuel due to an excessive fuel consumption rate through the gas-generator.
  Failed launch of an E-6LS radio-equipped version of the E-6 used to test tracking and communications networks for the Soviet manned lunar program. Suggestions for the abnormal consumption included the seizing up of a pintle valve for controlling fuel supply into the regulator or the seizing up of the fuel inlet control. The upper stages broke up in the atmosphere.

• 1968 April 7 - Luna 14 - Program: Lunar L3. Launch Site: Baikonur. Launch Complex: LC1. Launch Vehicle: Soyuz. Mass: 1,700 kg (3,700 lb).
  Lunar Orbiter; studied lunar gravitational field, Earth-Moon gravitational relationship, and conducted further scientific experiments in circumlunar space. Not revealed until years later was that the E-6LS was primarily intended to test tracking and communications networks for the Soviet manned lunar program. The Luna 14 spacecraft entered a 140 x 870 km x 42 degree lunar orbit on April 10, 1966. The spacecraft instrumentation was similar to that of Luna 10 and provided data for studies of the interaction of the earth and lunar masses, the lunar gravitational field, the propagation and stability of radio communications to the spacecraft at different orbital positions, solar charged particles and cosmic rays, and the motion of the Moon. This flight was the final flight of the second generation of the Luna series.