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36-581: The M-1 traces its history to US Air Force studies from the late 1950s for its launch needs in the 1960s. By 1961 these had evolved into the Space Launcher System design. The SLS consisted of a series of four rocket designs, all built around a series of solid-fuel boosters and liquid-hydrogen -powered upper stages. The smallest model, intended to launch the Dyna-Soar , used two 100-inch (2,500 mm) solids and an "A" liquid core. To power

72-656: A centrifugal pump , where the pumping is done by throwing fluid outward at high speed, or an axial-flow pump , where alternating rotating and static blades progressively raise the pressure of a fluid. Axial-flow pumps have small diameters but give relatively modest pressure increases. Although multiple compression stages are needed, axial flow pumps work well with low-density fluids. Centrifugal pumps are far more powerful for high-density fluids but require large diameters for low-density fluids. High-pressure pumps for larger missiles had been discussed by rocket pioneers such as Hermann Oberth . In mid-1935 Wernher von Braun initiated

108-425: A "turbopump with a rocket attached"–up to 55% of the total cost has been ascribed to this area. Common problems include: In addition, the precise shape of the rotor itself is critical. Steam turbine -powered turbopumps are employed when there is a source of steam, e.g. the boilers of steam ships . Gas turbines are usually used when electricity or steam is not available and place or weight restrictions permit

144-471: A few bars is not uncommon. Their advantage is a much higher volumetric flowrate. For this reason they are common for pumping liquid hydrogen in rocket engines, because of its much lower density than other propellants which usually use centrifugal pump designs. Axial pumps are also commonly used as "inducers" for centrifugal pumps, which raise the inlet pressure of the centrifugal pump enough to prevent excessive cavitation from occurring therein. Turbopumps have

180-479: A fuel pump project at the southwest German firm Klein, Schanzlin & Becker that was experienced in building large fire-fighting pumps. The V-2 rocket design used hydrogen peroxide decomposed through a Walter steam generator to power the uncontrolled turbopump produced at the Heinkel plant at Jenbach , so V-2 turbopumps and combustion chamber were tested and matched to prevent the pump from overpressurizing

216-539: A lunar landing. Like the Air Force, their Project Apollo initially favoured a direct ascent profile, requiring a large booster to launch the spacecraft into LEO. Prior to NASA taking over Wernher von Braun 's Saturn work for the US Army , they had no large rocket designs of their own, and started a study program known as Nova to study a range of options. Initially, the payload requirements were fairly limited, and

252-453: A massive 125,000 lb (57,000 kg) payload to LEO. Nova designs of this capability were quickly presented with up to eight F-1 engines, along with much more powerful upper stages that demanded the M-1 engine. Thus, for a brief period, the M-1 was used on the baseline designs for both NASA's and the Air Force's lunar programs. In 1961, President John F. Kennedy announced the goal of landing

288-469: A person on the Moon before the decade was out. After a brief argument, NASA won the mission over the Air Force. However, Nova would require massive manufacturing capability that did not currently exist, and it was not clear that booster construction could be started in time for a landing before 1970. By 1962 they had decided to use von Braun's Saturn V design, which went through a process of re-design to produce

324-419: A reputation for being extremely hard to design to get optimal performance. Whereas a well engineered and debugged pump can manage 70–90% efficiency, figures less than half that are not uncommon. Low efficiency may be acceptable in some applications, but in rocketry this is a severe problem. Turbopumps in rockets are important and problematic enough that launch vehicles using one have been caustically described as

360-529: A second series of design studies, also known as Nova, although they were essentially unrelated to the earlier designs. Many of the new designs used the M-1 as their second-stage engine, although demanding much higher payloads. In order to meet these goals, the M-1 project was uprated from 1.2 million pounds force to a nominal 1.5 million pounds force, and the designers deliberately added more turbopump capability to allow it to expand to at least 1.8 million and potentially up to 2.0 million pounds force. Additionally,

396-405: A small combustor to provide hot gases for running the fuel pumps. In the case of the M-1, the hydrogen and oxygen turbopumps were completely separate, each using their own turbine, rather than running both off a common power shaft. The hydrogen and oxygen pumps were some of the most powerful ever built at the time, producing 75,000 horsepower for the former, and 27,000 hp (20,000 kW) for

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432-471: A usable booster that could be built in the existing facilities at Michoud, Louisiana . With the selection of Saturn for the lunar missions, work on Nova turned to the post-Apollo era. The designs were re-targeted for crewed planetary expeditions, namely a crewed landing on Mars . Even utilizing a lightweight mission profile like that selected for Apollo, a Mars mission required a truly massive payload of about one million pounds to low Earth orbit. This led to

468-625: Is a stub . You can help Misplaced Pages by expanding it . Turbopump A turbopump is a propellant pump with two main components: a rotodynamic pump and a driving gas turbine , usually both mounted on the same shaft, or sometimes geared together. They were initially developed in Germany in the early 1940s. The purpose of a turbopump is to produce a high-pressure fluid for feeding a combustion chamber or other use. While other use cases exist, they are most commonly found in liquid rocket engines. There are two common types of pumps used in turbopumps:

504-464: Is lost. The volute or diffuser turns the high kinetic energy into high pressures (hundreds of bars is not uncommon), and if the outlet backpressure is not too high, high flow rates can be achieved. Axial turbopumps also exist. In this case the axle essentially has propellers attached to the shaft, and the fluid is forced by these parallel with the main axis of the pump. Generally, axial pumps tend to give much lower pressures than centrifugal pumps, and

540-434: The brazed impeller and it flew apart. A new one was made by milling from a solid block of aluminum . The next two runs with the new pump were a great disappointment; the instruments showed no significant flow or pressure rise. The problem was traced to the exit diffuser of the pump, which was too small and insufficiently cooled during the cool-down cycle so that it limited the flow. This was corrected by adding vent holes in

576-473: The "A" booster, Aerojet was contracted to convert an LR-87 , used in the Titan II missile , to run on liquid hydrogen. A prototype was successfully tested between 1958 and 1960. Initial studies of the 100-inch (2,500 mm) solid were also handed to Aerojet, starting in 1959. The SLS also envisioned a number of much larger designs intended to launch the Air Force's Lunex Project crewed lunar landing. Lunex

612-447: The "B" and "C" liquid stages. To provide the required power, the liquid stages mounted a cluster of twelve J-2s . To reduce this complexity, the Air Force also had Aerojet start studies of a much larger hydrogen-fueled design that would replace the twelve J-2s with only two engines. These initial studies would eventually emerge as the M-1, with a thrust of 1.2 million pounds force. When NASA formed in 1958, they also started planning for

648-697: The M-1 project in order to complete Saturn-related developments first. In 1965, another NASA project studied advanced versions of the Saturn, replacing the cluster of five J-2s on the S-II second stage with one M-1, five J-2Ts (an improved version of the J-2 with an aerospike nozzle), or a high-pressure engine known as the HG-3 , which would later become the direct predecessor of the Space Shuttle 's SSME . By 1966 it

684-515: The M-1 was even considered for a number of first-stage designs, in place of the F-1 or the 180-inch (4,600 mm) solids. For this role the specific impulse was dramatically reduced, and it appears that some consideration was given to various expanding nozzle designs to address this. M-1 development continued through this period, although as the Apollo program expanded, NASA started cutting funding to

720-648: The SLS provided wide flexibility in launch capability. The SLS was one of two programs being designed at different divisions within the Air Force, with the ultimate aim of providing the launch services for the X-20 Dyna Soar crewed spaceplane . Its competition was an upgraded version of the Titan I with a new upper stage that produced the Titan C concept. In the end, neither SLS or Titan C would be developed, in its place

756-569: The chamber. The first engine fired successfully in September, and on August 16, 1942, a trial rocket stopped in mid-air and crashed due to a failure in the turbopump. The first successful V-2 launch was on October 3, 1942. The principal engineer for turbopump development at Aerojet was George Bosco . During the second half of 1947, Bosco and his group learned about the pump work of others and made preliminary design studies. Aerojet representatives visited Ohio State University where Florant

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792-403: The end of 1948, Aerojet had designed, built, and tested a liquid hydrogen pump (15 cm diameter). Initially, it used ball bearings that were run clean and dry, because the low temperature made conventional lubrication impractical. The pump was first operated at low speeds to allow its parts to cool down to operating temperature . When temperature gauges showed that liquid hydrogen had reached

828-439: The engine per second. The Electron Rocket's Rutherford became the first engine to use an electrically-driven pump in flight in 2018. Most turbopumps are centrifugal - the fluid enters the pump near the axis and the rotor accelerates the fluid to high speed. The fluid then passes through a volute or a diffuser, which is a ring with multiple diverging channels. This causes an increase in dynamic pressure as fluid velocity

864-454: The favoured Nova designs used a first stage with four F-1 engines and a payload of about 50,000 lb (23,000 kg). These designs were presented to President Dwight D. Eisenhower on January 27, 1959. However, the Apollo spacecraft requirements quickly grew, settling on a 10,000 lb (4,500 kg) spacecraft (the CSM ) with a three-person crew. To launch such a craft to the Moon required

900-522: The fuel flow into the main engine and gas generator. The main engine was ignited by a spray of sparks directed into the combustion chamber from a pyrotechnic device. Shutdown was achieved by simply turning off the fuel flow to the gas generator, allowing the pumps to slow down on their own. The use of separate turbopumps and other components allowed the various parts of the M-1 to be built and tested individually. Space Launcher System The Space Launching System , or Space Launcher System , ( SLS ),

936-413: The latter. In most American designs, a gas-generator engine would dump the exhaust from the turbines overboard. In the case of the M-1, the resulting exhaust was relatively cool, and was instead directed into cooling pipes on the lower portion of the engine skirt. This meant that liquid hydrogen was needed for cooling only on the high-heat areas of the engine—the combustion chamber, nozzle and upper part of

972-504: The new Titan III was selected, combining the new missile of the Titan C with the solid boosters of the SLS. The SLS was also needed for the Lunex Project , a proposed human lunar landing in 1967. The replacing Titan III was more formally known as Program 624A (SSLS), Standard Space Launch System, Standardized Space Launch System, Standardized Space Launching System or Standard Space Launching System. This rocketry article

1008-627: The pump housing; the vents were opened during cool down and closed when the pump was cold. With this fix, two additional runs were made in March 1949 and both were successful. Flow rate and pressure were found to be in approximate agreement with theoretical predictions. The maximum pressure was 26 atmospheres (26 atm (2.6 MPa; 380 psi)) and the flow was 0.25 kilogram per second. The Space Shuttle main engine 's turbopumps spun at over 30,000 rpm, delivering 150 lb (68 kg) of liquid hydrogen and 896 lb (406 kg) of liquid oxygen to

1044-424: The pump, an attempt was made to accelerate from 5000 to 35 000 revolutions per minute. The pump failed and examination of the pieces pointed to a failure of the bearing, as well as the impeller . After some testing, super-precision bearings, lubricated by oil that was atomized and directed by a stream of gaseous nitrogen, were used. On the next run, the bearings worked satisfactorily but the stresses were too great for

1080-446: The skirt—reducing plumbing complexity considerably. The gas entered the skirt area at about 700 °F (371 °C), heating to about 1,000 °F (538 °C) before being dumped through a series of small nozzles at the end of the skirt. The exhaust added 28,000 lbf (120 kN) of thrust. The engine was started by rotating the pumps to operating speed using helium gas stored in a separate high-pressure container. This started

1116-412: The three-year lifetime of the project, a total of eight combustion chambers were built (two of them uncooled test units), eleven gas generators, four oxygen pumps, as well as four hydrogen pumps that were in the process of being completed. Scaled down models of the pumps were used during design/development to 1963. The M-1 used the gas-generator cycle , burning some of its liquid hydrogen and oxygen in

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1152-473: The use of more efficient sources of mechanical energy. One of such cases are rocket engines , which need to pump fuel and oxidizer into their combustion chamber . This is necessary for large liquid rockets , since forcing the fluids or gases to flow by simple pressurizing of the tanks is often not feasible; the high pressure needed for the required flow rates would need strong and thereby heavy tanks. Ramjet motors are also usually fitted with turbopumps,

1188-545: Was a 1960s-era design program of the US Air Force for a family of launch vehicles based around a set of common components. After a series of studies in the late 1950s, the Air Force had concluded that the maximum efficiency would be gained by using only liquid hydrogen fuel for upper stages, which demanded the use of boosters based on segmented solid fuel rockets . By combining one of three upper stages with three different diameters of solids built to any length needed,

1224-413: Was a direct landing mission, in which a single very large spacecraft would fly to the Moon, land, and return. In order to launch such a design to low Earth orbit (LEO), a very large booster with a 125,000 lb (57,000 kg) payload would be required. These larger SLS designs followed the same basic outline as the smaller Dynasoar booster, but used much more powerful 180-inch (4,600 mm) solids and

1260-640: Was clear that present funding levels for NASA would not be maintained in the post-Apollo era. The Nova design studies ended that year, and the M-1 along with it. The last M-1 contract expired on August 24, 1965, although testing continued on existing funds until August 1966. Studies on the J-2T ended at the same time. Although the HG-3 was never built, its design formed the basis for the Space Shuttle Main Engine . The final report (1966) found: Over

1296-461: Was working on hydrogen pumps, and consulted Dietrich Singelmann , a German pump expert at Wright Field. Bosco subsequently used Singelmann's data in designing Aerojet's first hydrogen pump. By mid-1948, Aerojet had selected centrifugal pumps for both liquid hydrogen and liquid oxygen . They obtained some German radial-vane pumps from the Navy and tested them during the second half of the year. By

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