Mission Type: Orbiter
Launch Vehicle: 8K82K + Blok D (Proton no. 240-01)
Launch Site: NIIP-5 / launch site 81L
Spacecraft Mass: about 3,800 kg
Spacecraft Instruments: 1) radiometer; 2) instrument to measure water vapor levels; 3) ultraviolet spectrometer; 4) radiation detector; 5) gamma spectrometer; 6) hydrogen/helium mass spectrometer; 7) spectrometer; 8) low-energy ion spectrometer and 9) imaging system (three cameras)
References:
Deep Space Chronicle: A Chronology of Deep Space and Planetary Probes 1958-2000, Monographs in Aerospace History No. 24, by Asif A. Siddiqi
Solar System Log by Andrew Wilson, published 1987 by Jane's Publishing Co. Ltd.
The M-69 series of Mars spacecraft was the first of a new generation of Mars probes designed by the Lavochkin design bureau for launch on the heavy Proton booster. The probes were designed around a single large spherical tank to which three pressurized compartments were attached. Although the 1969 missions were originally meant for both Mars orbit and landing, weight constraints late in mission design forced engineers to delete the lander and focus only on a Mars orbit mission.
After two en route midcourse corrections, the spacecraft were intended to enter orbit around Mars at roughly 1,700 x 34,000 kilometers at 40 degree inclination. After an initial photography mission, the probes would lower their pericenters to about 500 to 700 kilometers for a second imaging mission. Total mission lifetime would be about three months. During the launch of the first M-69, the Proton's third stage stopped firing at T+438.66 seconds, after its turbopump had caught on fire because of a faulty rotor bearing. The probe, scheduled to reach Mars orbit on 11 September 1969, never even reached Earth orbit.