Titan was a family of United States expendable rockets used between 1959 and 2005. The Titan I and Titan II were part of the US Air Force's intercontinental ballistic missile (ICBM) fleet until 1987. The space launch vehicle versions contributed the majority of the 368 Titan launches, including all the Project Gemini crewed flights of the mid-1960s. Titan vehicles were also used to lift US military payloads as well as civilian agency reconnaissance satellites and to send interplanetary scientific probes throughout the Solar System.
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.
RP-1 (alternatively, Rocket Propellant-1 or Refined Petroleum-1) is a highly refined form of kerosene outwardly similar to jet fuel, used as rocket fuel. RP-1 provides a lower specific impulse than liquid hydrogen (H2), but is cheaper, is stable at room temperature, and presents a lower explosion hazard. RP-1 is far denser than H2, giving it a higher energy density (though its specific energy is lower). RP-1 also has a fraction of the toxicity and carcinogenic hazards of hydrazine, another room-temperature liquid fuel.
A liquid-propellant rocket or liquid rocket utilizes a rocket engine burning liquid propellants. (Alternate approaches use gaseous or solid propellants.) Liquids are desirable propellants because they have reasonably high density and their combustion products have high specific impulse (Isp). This allows the volume of the propellant tanks to be relatively low.
Aerozine 50 is a 50:50 mix by weight of hydrazine and unsymmetrical dimethylhydrazine (UDMH), developed in the late 1950s by Aerojet General Corporation as a storable, high-energy, hypergolic fuel for the Titan II ICBM rocket engines. Aerozine continues in wide use as a rocket fuel, typically with dinitrogen tetroxide as the oxidizer, with which it is hypergolic. Aerozine 50 is more stable than hydrazine alone, and has a higher density and boiling point than UDMH alone.
The Rocketdyne H-1 was a 205,000 lbf (910 kN) thrust liquid-propellant rocket engine burning LOX and RP-1. The H-1 was developed for use in the S-I and S-IB first stages of the Saturn I and Saturn IB rockets, respectively, where it was used in clusters of eight engines. After the Apollo program, surplus H-1 engines were rebranded and reworked as the Rocketdyne RS-27 engine with first usage on the Delta 2000 series in 1974. RS-27 engines continued to be used up until 1992 when the first version of the Delta II, Delta 6000, was retired. The RS-27A variant, boasting slightly upgraded performance, was also used on the later Delta II and Delta III rockets, with the former flying until 2018.
The Titan IIIC was an expendable launch system used by the United States Air Force from 1965 until 1982. It was the first Titan booster to feature large solid rocket motors and was planned to be used as a launcher for the Dyna-Soar, though the spaceplane was cancelled before it could fly. The majority of the launcher's payloads were DoD satellites, for military communications and early warning, though one flight (ATS-6) was performed by NASA. The Titan IIIC was launched exclusively from Cape Canaveral while its sibling, the Titan IIID, was launched only from Vandenberg AFB.
The highest specific impulse chemical rockets use liquid propellants. They can consist of a single chemical or a mix of two chemicals, called bipropellants. Bipropellants can further be divided into two categories; hypergolic propellants, which ignite when the fuel and oxidizer make contact, and non-hypergolic propellants which require an ignition source.
The S-IB stage was the first stage of the Saturn IB launch vehicle, which was used for Earth orbital missions. It was an upgraded version of the S-I stage used on the earlier Saturn I rocket and was composed of nine propellant containers, eight fins, a thrust structure assembly, eight H-1 rocket engines, and many other components. It also contained the ODOP transponder. The propellant containers consisted of eight Redstone-derived tanks clustered around a Jupiter rocket-derived tank containing LOX. The four outboard engines gimballed to steer the rocket in flight, which required a few more engine components. The S-IB burned for nearly 2.5 minutes before separating at an altitude of 42 miles (68 km).
The gas-generator cycle, also called open cycle, is one of the most commonly used power cycles in bipropellant liquid rocket engines.
The AJ10 is a hypergolic rocket engine manufactured by Aerojet Rocketdyne. It has been used to propel the upper stages of several launch vehicles, including the Delta II and Titan III. Variants were and are used as the service propulsion engine for the Apollo command and service module, in the Space Shuttle Orbital Maneuvering System, and on the European Service Module – part of NASA's Orion spacecraft.
The SM-68 Titan was the designation of two intercontinental ballistic missiles developed for the United States Air Force. The Titan I and Titan II missiles were operational between 1962 and 1987 during the Cold War. These missiles, particularly the Titan II, were the basis of the Titan family of space launch vehicles.
The Titan II GLV or Gemini-Titan II was an American expendable launch system derived from the Titan II missile, which was used to launch twelve Gemini missions for NASA between 1964 and 1966. Two uncrewed launches followed by ten crewed ones were conducted from Launch Complex 19 at the Cape Canaveral Air Force Station, starting with Gemini 1 on April 8, 1964.
The LR87 was an American liquid-propellant rocket engine used on the first stages of Titan intercontinental ballistic missiles and launch vehicles. Composed of twin motors with separate combustion chambers and turbopump machinery, it is considered a single unit and was never flown as a single combustion chamber engine or designed for this. The LR87 first flew in 1959.
The RD-0243 is a propulsion module composed of an RD-0244 main engine and a RD-0245 vernier engine. Both are liquid rocket engine, burning N2O4 and UDMH. The RD-0244 main engine operates in the oxidizer rich staged combustion cycle, while the vernier RD-0245 uses the simpler gas generator cycle. Since volume is at a premium on submarine launches, this module is submerged on the propellant tank. Its development period was from 1977 to 1985, having had its first launch on December 27, 1981. Originally developed for the RSM-54, it was used later for the Shtil'.
The RD-263 (GRAU Index 15D117) is a liquid rocket engine, burning N2O4 and UDMH in the oxidizer rich staged combustion cycle. Four RD-263 engines form a propulsion module RD-264 (GRAU Index 15D119). For the R-36M KB Yuzhnoye only ordered the first stage propulsion to Energomash, instead of both stages, arguing that they were overworked with the RD-270 development. By April 1970 Yuzhnoye was getting the engine documentation. By the end of 1972 Energomash started to test fire the engines in its own test stand. And by September 1973 the engine was certified for flight. While the engine is out of production, the ICBM as well as the Dnepr remain operational as of 2015.
The RD-119 was a liquid rocket engine, burning liquid oxygen and UDMH in the gas-generator cycle. It has a huge expansion ratio on the nozzle and uses a unique propellant combination to achieve an extremely high isp of 352 s for a semi-cryogenic gas-generator engine. It also has a unique steering mechanism. The engine main nozzle is fixed, and the output of the gas generator is fed into four nozzles on the side of the engine. Instead of using gimbaled verniers to supply vector control, the combustion gases are distributed by an electrically driven system that can control the thrust among the nozzles.
The RD-214 (GRAU Index 8D59) was a liquid rocket engine, burning AK-27I (a mixture of 73% nitric acid and 27% N2O4 + iodine passivant and TM-185 (a kerosene and gasoline mix) in the gas generator cycle. As was the case with many V-2 influenced engines, the single turbine was driven by steam generated by catalytic decomposition of hydrogen peroxide. It also had four combustion chambers and vector control was achieved by refractory vanes protruding into the nozzle's exhaust.
The Astris was a liquid rocket engine burning the hypergolic propellant combination of Aerozine 50 and N2O4. A single engine powered Astris third stage of the failed Europa rocket.
The YF-1 was a Chinese liquid rocket engine burning N2O4 and UDMH in a gas generator cycle. It is a basic engine which when mounted in a four engine module forms the YF-2. It was used as the basis for developing a high altitude version known as the YF-3.
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