Encyclopedia Astronautica
Nitric acid/Kerosene



rd214b.jpg
RD-214
Credit: © Mark Wade
Drawing on the German World War II Wasserfall rocket, nitric acid (HNO3) became the early storable oxidiser of choice for missiles and upper stages of the 1950's. To overcome various problems with its use, it was necessary to combine the nitric acid with N2O4 and passivation compounds. These formulae were considered extremely secret at the time. By the late 1950's it was apparent that N2O4 by itself was a better oxidiser. Therefore nitric acid was almost entirely replaced by pure N2O4 in storable liquid fuel rocket engines developed after 1960. Rocket propellant RP-1, or its foreign equivalents, is a straight-run kerosene fraction, which is subjected to further treatment, i.e., acid washing, sulphur dioxide extraction. Thus, unsaturated substances which polymerise in storage are removed, as are sulphur-containing hydrocarbons.

The propellant combinations WFNA/ JP-4 and later IRFNA/JP-4 were the first storable systems given serious consideration in the United States. Problems which caused the abandoning of these propellants were the absence of reliable hypergolic ignition and unstable combustion. IRFNA/UDMH and IRFNA/JP-X finally did prove satisfactory.

The composition of propellant-grade nitric acids is covered by Military Specification MIL-N-7254. The nitric acids are fuming liquids which vary from colorless to brown, depending on the amount of dissolved N2O4. The vapours from these acids have a characteristic pungent odour. They are highly corrosive, toxic, oxidising agents and attack most metals. They react with most organic materials violently enough to cause fire. The acids are soluble in water in all proportions, with an accompanying evolution of heat. They cannot be made to explode. Approximately 90 per cent of the nitric acid is made by the catalytic oxidation of ammonia with air or oxygen to yield nitric oxide (NO). The latter is oxidised to N2O4 which, when treated with water, yields nitric acid (HNO3) and may be concentrated by distillation with sulphuric acid. Red fuming nitric acids may be produced by passing gaseous N2O4 into nitric acid, a slight modification of the above process. Production of nitric acid was estimated at 3 million tonnes in 1959. The price of RFNA was $ 0.20 per kg in drum lots; IRFNA was slightly higher. The varieties of nitric acid propellants include:

  • WFNA - White fuming nitric acid is based on anhydrous nitric acid (HNO3), a colourless corrosive liquid which fumes in moist air. They contain a maximum of 2 per cent water and 0.5 per cent nitrogen dioxide, and decompose to yield amounts of water, nitrogen dioxide, and oxygen which are in chemical equilibrium.

  • IWFNA - Inhibited white fuming nitric acid. Since container materials are attacked by WFNA and equilibrium products, 0.6 per cent HF is added for passivation by deposition of a protective metallic fluoride coating.

  • RFNA - Red fuming nitric acid. Since WFNA or IWFNA exhibit excessive equilibrium decomposition pressures, reaching 75 bar at 700 deg C. To suppress the high pressure through a mass-action effect, some 13 per cent N2O4 and 3 per cent H20 are added, in order to reduce equilibrium pressures to 2 bar at 700 deg C. The colour of the resulting red fuming nitric acid is imparted by N204.

  • IRFNA - Inhibited red fuming nitric acid. Addition of 0.6 per cent HF to RFNA produces inhibited RFNA (IRFNA). The IRFNA specification was published in 1954 and thereafter Russian rocket engines using the same fuel appeared.

  • AK20 - Russian formulation consisting of 80% nitric acid + 20% N2O4 (AK = Azotna Kislota = Nitric Acid)

  • AK20F - Russian formulation consisting of 80% nitric acid + 20% N2O4 + fluorine passivant

  • AK20I - Russian formulation consisting of 80% nitric acid + 20% N2O4 + iodine passivant

  • AK20K - Russian formulation consisting of 80% nitric acid + 20% N2O4 + unknown additive

  • AK27I - Russian formulation consisting of 73% nitric acid + 27% N2O4 + iodine passivant

  • AK-27P - Russian formulation consisting of 73% nitric acid + 27% N2O4 + unknown additive

Rocket propellant RP-1 is a straight-run kerosene fraction, which is subjected to further treatment, i.e., acid washing, sulphur dioxide extraction. Thus, unsaturated substances which polymerise in storage are removed, as are sulphur-containing hydrocarbons. Furthermore, in order to meet specification requirements of density, heat of combustion, and aromatic content, the kerosene must be obtained from crudes with a high naphthene content. RP-1 is an excellent solvent for many organic materials. The flash point is above 43 deg C. Above that temperature RP-1 will form explosive mixtures with air. The temperature range for explosive mixtures (rich limit) is 79 to 85 deg C. RP-1 is not so toxic as the JP series of fuels because of its lower aromatic content. In the United States, suitable kerosene fractions in 1960 were limited almost exclusively to the West Coast. The estimated 1956 United States production was 7700 tonnes, and the price was $0.05 per kg. By the 1980's it was typically $ 0.20 per kg. Russian formulations have typical densities of 0.82 to 0.85 g/cc, and even higher densities were achieved in the N1 and Soyuz 11A511U rockets by superchilling the fuel prior to loading.

Oxidizer: Nitric acid. Fuel: Kerosene. Propellant Formulation: IRFNA/RP-1. Optimum Oxidizer to Fuel Ratio: 4.8. Temperature of Combustion: 3,235 deg K. Ratio of Specific Heats: 1.23. Density: 1.35 g/cc. Characteristic velocity c: 1,610 m/s (5,280 ft/sec). Isp Shifting: 268 sec. Isp Frozen: 258 sec. Mol: 25.00 M (82.00 ft). Oxidizer Density: 1.510 g/cc. Oxidizer Freezing Point: -42 deg C. Oxidizer Boiling Point: 86 deg C. Fuel Density: 0.806 g/cc. Fuel Freezing Point: -73 deg C. Fuel Boiling Point: 147 deg C.

Location: 1610.
Specific impulse: 314 s.
Specific impulse sea level: 268 s.

More... - Chronology...


Associated Spacecraft
  • RP-318 Russian manned rocketplane. Korolev adapted his SK-9 glider in 1936 as the first rocked-powered aircraft in the Soviet Union. More...
  • BI-1 Russian manned rocketplane. Flown 1941. The Bereznyak-Isayev BI-1 was the first high speed rocket plane developed by the Soviet Union. Drawings were completed by spring 1941 but Stalin did not give the go-ahead for production until July 9, 1941. More...
  • Malyutka Russian manned rocketplane. Cancelled 1944. The Malyutka rocket point interceptor was designed by Polikarpov beginning in 1943. More...
  • I-270 Russian manned rocketplane. Flown 1947. The MiG I-270 rocketplane began as a post-war copy of the German Ju-248 (Me-263) design. The resulting rocketplane had a more refined aerodynamic form than the Me-263 and lower gross weight. More...
  • Samolyot 5 Russian manned rocketplane. Cancelled 1949. Bisnovat was assigned the project to develop an all-Soviet equivalent to the 346 supersonic rocketplane being developed by the German Roessing team in OKB-2. More...

Associated Engines
  • Isayev R-17 Isayev Nitric acid/Kerosene rocket engine. 131.2 kN. R-17. Out of production. Designation unknown. First flight 1961. More...
  • R-56 Blok A Notional Nitric acid/Kerosene rocket engine. 4412 kN. R-56 Blok A. Notional engines for polyblock R-56, immense booster/ICBM; planned range 16,000 km. payload 35,000 kg. Tsniimash has 1:10 structural simulation model. Isp=320s. More...
  • R-56 Blok B Notional Nitric acid/Kerosene rocket engine. 784 kN. R-56 Blok B. Notional engines for polyblock R-56, immense booster/ICBM; planned range 16,000 km. payload 35,000 kg. Tsniimash has 1:10 structural simulation model. Isp=330s. More...
  • RD-1KhZ Glushko Nitric acid/Kerosene rocket engine. 2.940 kN. take-off acelleration of Pe-2R, La-7R, Yak-3, Su-6, Su-7, La-120R airplanes. Developed 1941-46. The RD-1KhZ was a variant of the RD-1 engine with chemical ignition. Production 1944-45. Isp=200s. More...
  • RD-1 Glushko Nitric acid/Kerosene rocket engine. 2.940 kN. Take-off acelleration of Pe-2, La-7, Yak-3, Su-6 airplanes. Developed 1941-45. First Russian liquid propellant rocket engine. Production 1944-45. Ignition was by an ethane-air mixture. Isp=200s. More...
  • RD-2MZV-F Dushkin Nitric acid/Kerosene rocket engine. 19.6 kN. Samolet 5. Developed 1946. More...
  • RD-2MZV Dushkin Nitric acid/Kerosene rocket engine. 13.7 kN. I-270. Developed 1944-47. Thrust variable 0.1-0.3 tf / 0.35-1.4 tf. More...
  • RD-214 Glushko Nitric acid/Kerosene rocket engine. 730 kN. R-12, Kosmos 11K63 stage 1. Isp=264s. Single turbopump driven by H2O2 gas generator feeding four fixed chambers. Ignition with propellant TG-02. First flight 1957. More...
  • RD-213 Glushko Nitric acid/Kerosene rocket engine. 755 kN. Winged rocket M-40 (2). Development ended 1957. Two thrust levels. Ignition with propellant TG-02. Chamber pressure 233,8 / 46,6 bar. Specific impulse 223 / 231 sea level. Isp=254s. More...
  • RD-212 Glushko Nitric acid/Kerosene rocket engine. 623 kN. Developed 1952-56. Isp=253s. Original four-chamber engine design planned for the booster stage of the Buran intercontinental ramjet missile. Abandoned due to limited thrust; RD-213 was developed instead. More...
  • RD-211 Glushko Nitric acid/Kerosene rocket engine. 642.3 kN. long-distance missile. Developed 1952-55. Original four-chamber engine design planned for use on the R-12 IRBM. Abandoned due to limited thrust and the RD-214 was developed in its place. Isp=261s. More...
  • RD-210 Glushko Nitric acid/Kerosene rocket engine. 29.850 kN. vertical sounding rocket. Developed -1954. Isp=241s. More...
  • RD-2 Glushko Nitric acid/Kerosene rocket engine. 6 kN. experimental. Developed 1945-47. The RD-2 was based on the RD-1 engine. Used chemical ignition. Isp=200s. More...
  • RD-200 Glushko Nitric acid/Kerosene rocket engine. 98.508 kN. vertical sounding rocket. Developed -1951. Isp=234s. More...
  • RD-3 Glushko Nitric acid/Kerosene rocket engine. 9 kN. experimental. Developed 1950's. The RD-3 was a cluster of three RD-1 engines with a new common turbopump. Ignition was by an ethane-air mixture. Isp=190s. More...
  • S-3-20M5A Dushkin Nitric acid/Kerosene rocket engine. U-21. Developed -1959. Launch thrust 29.4 kN. More...
  • S2.253A Isayev Nitric acid/Kerosene rocket engine. 93 kN. R-11FM. Out of Production. Used in R-11FM submarine version of Scud B. Fuel Kerosene T-1, chemical ignition by TG-02. Mixture ratio derived from tank content. 81 kN sea-level. More...
  • S2.253 Isayev Nitric acid/Kerosene rocket engine. 93.3 kN. R-11 (Scud B) 8A61. Thrust 8300 kgf at sea level. Fuel Kerosene T-1, chemical ignition by TG-02. Isp=251s. First flight 1953. More...
  • YF-1 CALT Nitric acid/kerosene rocket engine. 300 kN. More...
  • YLR45-AJ-1 Aerojet Nitric acid/Kerosene rocket engine. B-47C ATO. Out of Production. Development begun August 1948. Turbojet engine bleed air drive for turbopump. Fixed internal acid tanks, regenerative cooling. More...
  • YLR45AJ-3 Aerojet Nitric acid/Kerosene rocket engine. F-84 ATO. Out of Production. Development begun 1948. Bleed air drive, droppable acid tanks, ceramic chamber with oval throat, 60 second duration, reusable 50 times More...

Associated Stages
  • Buran M-41 Nitric acid/Kerosene propellant rocket stage. Loaded/empty mass 18,000/3,000 kg. Thrust 755.00 kN. Vacuum specific impulse 254 seconds. Booster for Buran missile. Four used to boost ramjet second stage to ignition conditions. Masses estimated based on missile known total mass. Specific impulse estimated. More...
  • DF-2-1 Nitric acid/kerosene rocket stage. 300.00 kN (67,443 lbf) thrust. Mass 30,000 kg (66,139 lb). More...
  • DF-2A-1 Nitric acid/kerosene rocket stage. 300.00 kN (67,443 lbf) thrust. Mass 30,000 kg (66,139 lb). More...
  • Hwasong 5 Nitric acid/Kerosene propellant rocket stage. Loaded mass 5,000 kg. Thrust 93.00 kN. More...
  • Hwasong 6 Nitric acid/Kerosene propellant rocket stage. Loaded mass 5,000 kg. Thrust 93.00 kN. More...
  • Kosmos A-1 Nitric acid/Kerosene propellant rocket stage. Loaded/empty mass 39,515/3,150 kg. Thrust 730.50 kN. Vacuum specific impulse 264 seconds. More...
  • R-11 Nitric acid/Kerosene propellant rocket stage. Loaded/empty mass 4,660/955 kg. Thrust 93.28 kN. Vacuum specific impulse 251 seconds. First Russian ballistic missile using storable propellants. Enlargement/elaboration of German Wasserfall SAM. Developed by Korolev OKB, then Makeyev OKB spun off to develop Army and SLBM derivatives. Range 270 km with 690 kg, accuracy 1.5 km/0.75 km. Maximum altitude 78 km. Time of flight 5.4 minutes. Max velocity at burnout 1430 m/s. Source: Wall chart, Russian Space Agency HQ, Moscow. More...
  • R-11FM Nitric acid/Kerosene propellant rocket stage. Loaded/empty mass 4,473/1,080 kg. Thrust 92.83 kN. Vacuum specific impulse 250 seconds. First Russian submarine-launched ballistic missile. Range 150 km with 967 kg warhead. Accuracy 1.5 km in range, 0.75 km lateral. More...
  • R-12 Nitric acid/Kerosene propellant rocket stage. Loaded/empty mass 34,610/4,810 kg. Thrust 625.52 kN. Vacuum specific impulse 235 seconds. Payload 390 kg. Range 1500 km. Maximum altitude 398 km. Time of flight 11.8 minutes. Max velocity at burnout 3530 m/s. Accuracy 6 km in range, 5 km laterally. Source: wall chart, Russian Space Agency HQ, Moscow. More...
  • R-17 Nitric acid/Kerosene propellant rocket stage. Loaded/empty mass 5,385/1,645 kg. Thrust 93.10 kN. Vacuum specific impulse 251 seconds. Developed from Russian storable fuel tactical missile. Original R-11 designed by Korolev OKB, subsequent developments by Makeyev OKB. Using calculations of Gerald Bull, stretched and clustered as basis of Iraqi ICBM/satellite launch vehicle. More...
  • R-56 Polyblock Stage A Nitric acid/Kerosene propellant rocket stage. Loaded/empty mass 222,000/18,000 kg. Thrust 4,410.00 kN. Vacuum specific impulse 320 seconds. Range 16,000 km. Payload 35,000 kg. Tsniimash has 1:10 structural simulation model. Three stage carrier rocket with consecutiveively divided first and paraell divided second stages. Work began in 1961. Chief designer Yangel. Source: Placard, TsNIIMASH. More...
  • R-56 Polyblock Stage B Nitric acid/Kerosene propellant rocket stage. Loaded/empty mass 55,500/5,000 kg. Thrust 784.00 kN. Vacuum specific impulse 330 seconds. More...

Home - Browse - Contact
© / Conditions for Use