The Russian Proton rocket
FROM ILS PRESS KIT
Posted: June 14, 2001
Proton's fourth stage possesses a multiple restart capability that allows it to perform all orbit change maneuvers necessary to place a spacecraft into its final orbit, without requiring use of the spacecraft's on-board propellant supply. Proton can deliver payloads of up to 22 metric tons to low-earth orbit, or up to 2.1 metric tons to geosynchronous orbit.
Background and History
Proton has flown more than 200 missions and has orbited the Salyut series space stations and the Mir Space station modules. It has launched the Ekran, Raduga, and Gorizont series of geostationary communications satellites (which provided telephone, telegraph, and television service within Russia and between member states of the Intersputnik Organization), as well as the Zond, Luna, Venera, Mars, Vega, and Phobos inter-planetary exploration spacecraft. The Proton has also launched the entire constellation of Glonass position location satellites. All Russian geostationary and interplanetary missions are launched on Proton. Approximately 90% of all Proton launches have been the four-stage version.
The Proton launch vehicle has a long history of outstanding reliability. From its first operational launch in 1970 to the present day, Proton has averaged a 92.5% success rate. Today, the Proton launch vehicle has a 92% (moving average) success rate over its last 50 launches.
The Proton family
Overall height of the vehicle in either configuration is approximately 61 m (200 ft), while the diameter of the second and third stages, and of the first stage core tank, is 4.1 m (13.5 ft). Maximum diameter of the first stage, including the outboard fuel tanks, is 7.4 m (24.3 ft). The Block DM fourth stage, when present, has an external diameter of 3.7 m (12.1 ft). Total weight of the Proton at launch is approximately 691,500 kg (1,524,000 lbm).
D-1-e (Four-Stage) Configuration
The Block DM (fourth stage) is optimized for multi-burn space transfer operations. Its main engine (model number 11D58M) delivers a vacuum thrust of 83.5n (1.88 x 10 4 lbf), is gimbaled to provide three-axis control during powered flight operations, and can be restarted as many as seven times during flight. The stage is 3.7 m (12.1 ft) in diameter, 6.28 m (20.6 ft) in length, with an inert mass at separation of 2,440 kg (5,378 lbm) and a total propellant mass of 15,050 kg (33,180 lbm). It is three-axis stabilized in unpowered flight by a storable bipropellant (N 2 O 4 /UDMH) attitude control system, comprised of two "SOZ" (or "micro") thruster units located at the base of the Block DM. Guidance, navigation, and control of the fourth stage are provided by a triple redundant digital avionics package, which can be ground commanded in flight, if necessary.
Multiple payload fairings are available for the Proton. It is a two-piece, hinged, clamshell structure of monocoque composite sandwich construction. It does not incorporate separation rocket motors, and no pyro gases are released during operation.
Flight data file
Vehicle: Proton/Block DM
Payload: ASTRA 2C
Launch date: June 16, 2001
Launch time: 0149 GMT (9:49 p.m. EDT on June 15)
Launch site: LC 81, Pad 23, Baikonur Cosmodrome, Kazakhstan
Satellite broadcast: Telstar 5, Trans. 23, C-band
Launch timeline - Chart with times and descriptions of events to occur during the launch.
ASTRA 2C - Learn more about the Proton's satellite cargo.
MISSION STATUS CENTER