RD-270 (,

GRAU index The Main Missile and Artillery Directorate of the Ministry of Defense of the Russian Federation (), commonly referred to by its transliterated acronym GRAU (), is a department of the Russian Ministry of Defense. It is subordinate to the Chief of ...

: 8D420) was a single-chamber liquid-fuel rocket engine designed by Energomash (

USSR The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

) in 1960–1970. It was to be used on the first stages of the proposed heavy-lift

UR-700 The Universal Rocket or ''UR'' family of missiles and carrier rockets is a Russian, previously Soviet rocket family. Intended to allow the same technology to be used in all Soviet rockets, the UR is produced by the Khrunichev State Research and P ...

and UR-900 rocket families, as well as on the N1. It has the highest thrust among single-chamber engines of the

, 640 metric tons at the surface of Earth. The propellants used are a

hypergolic A hypergolic propellant is a rocket propellant combination used in a rocket engine, whose components spontaneously ignite when they come into contact with each other. The two propellant components usually consist of a fuel and an oxidizer. The ...

mixture of

unsymmetrical dimethylhydrazine Unsymmetrical dimethylhydrazine (abbreviated as UDMH; also known as 1,1-dimethylhydrazine, heptyl or Geptil) is a chemical compound with the formula H2NN(CH3)2 that is primarily used as a rocket propellant. At room temperature, UDMH is a colorle ...

(UDMH) fuel with

dinitrogen tetroxide Dinitrogen tetroxide, commonly referred to as nitrogen tetroxide (NTO), and occasionally (usually among ex-USSR/Russian rocket engineers) as amyl, is the chemical compound N2O4. It is a useful reagent in chemical synthesis. It forms an equilibrium ...

() oxidizer. The chamber pressure was among the highest considered, being about 26 MPa. This was achieved by applying the

full-flow staged combustion cycle The staged combustion cycle (sometimes known as topping cycle, preburner cycle, or closed cycle) is a Liquid-propellant rocket#Engine cycles, power cycle of a bipropellant rocket Rocket engine, engine. In the staged combustion cycle, propellant ...

for all the incoming mass of fuel, which is turned into a gas and passes through multiple turbines before being burned in the combustion chamber. This allowed the engine to achieve a

specific impulse Specific impulse (usually abbreviated ) is a measure of how efficiently a reaction mass engine, such as a rocket engine, rocket using propellant or a jet engine using fuel, generates thrust. In general, this is a ratio of the ''Impulse (physics), ...

of at the Earth's surface. Engine testing was underway when the decision was made to cancel the program. Development was stopped with all other work on corresponding rocket projects on 11 December 1970.

History

The development of the RD-270 started on 26 June 1962. Preliminary investigations and development of the engine and its further production were performed under the guidance of

Valentin Glushko Valentin Petrovich Glushko (; ; born 2 September 1908 – 10 January 1989) was a Soviet engineer who was program manager of the Soviet space program from 1974 until 1989. Glushko served as a main designer of rocket engines in the Soviet progra ...

and finished in 1967. It became the most powerful engine in the world to date that used storable propellants. During 1967–1969, several test firings were performed with experimental engines that were adapted to work at sea level and had a short nozzle. In total, 27 test firings were performed with 22 engines; three engines were tested twice, and one of them was tested three times. The RD 270 was also considered for the R-56 rocket (although never formally adopted) until work on the design stopped in June 1964. During development, Glushko studied the use of pentaborane "zip" propellants in a modified RD-270M engine. This would have created immense toxicity problems but increased the specific impulse of the engine by .Astronautix: RD-270
.

Design

The engine throttle range was 95–105%, the thrust vector control range was ±12° (project R-56) and ±8° for

rocket family. The oxidizer-to-fuel ratio was 2.67 and could be changed by up to 7%. To achieve such a high

and pressure in

combustion chamber A combustion chamber is part of an internal combustion engine in which the air–fuel ratio, fuel/air mix is burned. For steam engines, the term has also been used for an extension of the Firebox (steam engine), firebox which is used to allow a mo ...

as RD-270 has, two circuits of

were applied. The pair of turbines with preburners turns the fuel into the gaseous form and circulates all of the fuel components. One of the turbines uses the fuel-rich gas to power a fuel pump, another one uses the oxidizer-rich gas to power the oxidizer pump. As a result, the main combustion chamber burns only generator gas. The engine controller regulates the functions of the two independent fuel and oxidizer circuits. To cool the MCC, its wall structure is layered, with four internal belts of slots. Some parts of the nozzle are covered by

zirconium dioxide Zirconium dioxide (), sometimes known as zirconia (not to be confused with zirconium silicate or zircon), is a white crystalline oxide of zirconium. Its most naturally occurring form, with a monoclinic crystalline structure, is the mineral bad ...

for thermal protection.

References

External links

Article title
{{Rocket engines Rocket engines of the Soviet Union Rocket engines using hypergolic propellant Rocket engines using full flow staged combustion cycle Energomash rocket engines

History

Design

See also

References

External links