Proton (rocket family)

Proton 8K82K
Launch of a Proton rocket. (NASA)
Stages		4
1 - Boosters	Engines	6 X RD-253-11D48
Thrust		1,745 kN X 6 = 10,470 kN
Burn time		124 seconds
Fuels		N2O4/UDMH
2 - Core Stage	Engines	4 X RD-0210
Thrust		600 kN X 4 = 2,400 kN
Burn time		206 seconds
Fuels		N2O4/UDMH
3 - 3rd Stage	Engine	1 X RD-0212
Thrust		630.2 kN
Burn time		238 seconds
Fuels		N2O4/UDMH
4 - Blok D Stage	Engine	1 X RD-58M
Thrust		85.02 kN
Burn time		610 seconds
Fuels		Lox/Kerosene
Launch Vehicle		1st Launch March 10, 1967
Payload LEO 51-deg		20,000 kg
Payload Geo-sync orbit		6,000 kg
Payload Escape Velocity		5,800 kg

The Proton rocket (formal designation: UR-500, also known as D-1) is a Russian unmanned space vehicle design first launched in 1965 and still in use as of 2005.

Proton initially started life as a "super ICBM." It was designed to throw a 10-MT (or larger) nuclear warhead over a distance of 12,000 km. It was, of course, hugely oversized for an ICBM and was never used in such a capacity. Its real purpose was as a launch vehicle. It was the brainchild of Vladimir Chelomei's design bureau as a foil to Sergei Korolev's N1 booster with the specific intent of sending a two man Zond craft around the moon. With the termination of the Saturn V programme Proton became the largest Expendable Launch Vehicle in service until the Energia rocket first flew in 1987.

Proton is fuelled by unsymmetrical dimethyl hydrazine and nitrogen tetroxide. These are hypergolic fuels which burn on contact, voiding the need for an ignition system. They are stored at ambient temperatures avoiding the need for low-temperature-tolerant components and also allowing the rocket to sit on the pad indefinitely without need for continuous topping up of boiling off cryogenic fuels. They are, however, very toxic fuels that require special handling care.

Between the first flight in 1965 and 1970, the Proton was a very unreliable launcher causing the loss of many space vehicles. By the early 1970s the flaws were worked out and it became a very reliable rocket which it remains to this day.

Proton launched the unmanned Soviet circumlunar flights and would very likely have launched the first humans to circle the Moon had the flight of Apollo 8 been conducted as originally planned (i.e. without going to Moon orbit). Proton launched the Salyut space stations, Mir core segment, and both Zarya and Zvezda of the ISS. It also launched many probes to the Moon, Mars, and Venus (using the 4-stage D-1e version).

Proton also launched commercial satellites, most of them being managed by the International Launch Services.

Launch capacity to low Earth orbit is about 20 metric tons. Interplanetary transfer capacity is about 5–6 metric tons.

Proton 8K82K Specifications

• Stage Number: 1. Proton K-1
  • Gross Mass: 450,510 kg
  • Empty Mass: 31,100 kg
  • Thrust (vac): 10,470 kN
  • Isp: 316 s (3.10 kN·s/kg)
  • Burn time: 124 s
  • Isp(sl): 267 s (2.62 kN·s/kg)
  • Diameter: 4.15 m
  • Span: 7.40 m
  • Length: 21.20 m
  • Propellants: N2O4/UDMH
  • Engines: 6 x RD-253-11D48
  • Other designations: 8S810K

• Stage Number: 2. Proton K-2
  • Gross Mass: 167,828 kg
  • Empty Mass: 11,715 kg
  • Thrust (vac): 2,399 kN
  • Isp: 327 s (3.21 kN·s/kg)
  • Burn time: 206 s
  • Isp(sl): 230 s (2.26 kN·s/kg)
  • Diameter: 4.15 m
  • Length: 14.00 m
  • Propellants: N2O4/UDMH
  • Engines: 4 RD-0210
  • Other designations: 8S811K.

• Stage Number: 3. Proton K-3
  • Gross Mass: 50,747 kg
  • Empty Mass: 4,185 kg
  • Thrust (vac): 630 kN
  • Isp: 325 s (3.19 kN·s/kg)
  • Burn time: 238 s
  • Diameter: 4.15 m
  • Length: 6.50 m
  • Propellants: N2O4/UDMH
  • Engines: 1. RD-0212

• Stage Number: 4
  • Proton 11S824
  • Gross Mass: 13,360 kg
  • Empty Mass: 1,800 kg
  • Thrust (vac): 83 kN
  • Isp: 346 s (3.39 kN·s/kg)
  • Burn time: 470 s
  • Diameter: 3.70 m
  • Length: 5.50 m
  • Propellants: Lox/Kerosene
  • Engines: 1. RD-58
  • Other designations: 11S824; Block D; D-1-e.

Proton M

Latest version is the Proton-M. A Proton M can launch 3 to 3.2 metric tons (6612 to 7053 lbm) into geostationary orbit or 5.5 metric tons (12,122 lbm) into a geostationary transfer orbit. It can place up to 22 metric tons (48,488 lbm) in low Earth orbit with a 51.6-degree inclination, the orbit of the International Space Station (ISS).

External link

• Proton rocket specifications sheet
• Proton M Debuts With Successful Ekran Launch on April 7, 2001