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 uses 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 II was an intercontinental ballistic missile (ICBM) developed by the Glenn L. Martin Company from the earlier Titan I missile. Titan II was originally designed and used as an ICBM, but was later adapted as a medium-lift space launch vehicle to carry payloads to Earth orbit for the United States Air Force (USAF), National Aeronautics and Space Administration (NASA) and National Oceanic and Atmospheric Administration (NOAA). Those payloads included the USAF Defense Meteorological Satellite Program (DMSP), NOAA weather satellites, and NASA's Gemini crewed space capsules. The modified Titan II SLVs were launched from Vandenberg Air Force Base, California, up until 2003.
Titan IV was a family of heavy-lift space launch vehicles developed by Martin Marietta and operated by the United States Air Force from 1989 to 2005. Launches were conducted from Cape Canaveral Air Force Station, Florida and Vandenberg Air Force Base, California.
Titan IIIB was the collective name for a number of derivatives of the Titan II ICBM and Titan III launch vehicle, modified by the addition of an Agena upper stage. It consisted of five separate rockets. The Titan-3B Agena-D was a basic Titan IIIA with an Agena D upper stage. The Titan 23B was a basic Titan II with an Agena upper stage, and the Titan 24B was the same concept, but using the slightly enlarged Titan IIIM rocket as the base. The Titan 33B was a Titan 23B with the Agena enclosed in an enlarged fairing, in order to allow larger payloads to be launched. The final member of the Titan IIIB family was the Titan 34B which was a Titan 24B with the larger fairing used on the Titan 33B.
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 Aerojet M-1 was one of the largest and most powerful liquid-hydrogen-fueled liquid-fuel rocket engines to be designed and component-tested. It was originally developed during the 1950s by the US Air Force. The M-1 offered a baseline thrust of 6.67 MN and an immediate growth target of 8 MN. If built, the M-1 would have been larger and more efficient than the famed F-1 that powered the first stage of the Saturn V rocket to the Moon.
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.
Rocketdyne's E-1 was a liquid propellant rocket engine originally built as a backup design for the Titan I missile. While it was being developed, Heinz-Hermann Koelle at the Army Ballistic Missile Agency (ABMA) selected it as the primary engine for the rocket that would emerge as the Saturn I. In the end, the Titan went ahead with its primary engine, and the Saturn team decided to use the lower-thrust H-1 in order to speed development. The E-1 project was cancelled in 1959, but Rocketdyne's success with the design gave NASA confidence in Rocketdyne's ability to deliver the much larger F-1, which powered the first stage of the Saturn V missions to the Moon.
Rocket propellant is used as reaction mass ejected from a rocket engine to produce thrust. The energy required can either come from the propellants themselves, as with a chemical rocket, or from an external source, as with ion engines.
Aestus is a hypergolic liquid rocket engine used on an upper stage of Ariane 5 family rockets for the orbital insertion. It features unique design of 132 coaxial injection elements causing swirl mixing of the MMH propellants with nitrogen tetroxide oxidizer. The pressure-fed engine allows for multiple re-ignitions.
The LR91 was an American liquid-propellant rocket engine, which was used on the second stages of Titan intercontinental ballistic missiles and launch vehicles. While the original version - the LR91-3 - ran on RP-1/LOX (as did the companion LR87-3) on the Titan I, the models that propelled the Titan II and later were switched to Aerozine 50/N2O4.
The LR-101 is a fixed thrust, single start vernier thruster developed by Rocketdyne in the mid-to-late fifties and used in the Atlas, Thor and Delta launch vehicles until 1990.
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