The History of the Rocket
The 1940's
The Marshall Space Flight Center is NASA’s primary propulsion center. The center started in then 1940’s in White Sands, New Mexico under contract by the US Army to develop missile and rocket technology. A German V-2 Rocket team was assembled under Wernher von Braun and brought to America in the early 1940’s. The German V-2 rocket had already been tested and used by Germany during the opening years of World War II. The V-2 was a 1,650-pound warhead and over 1,115 were launched against England and 1,675 were launched against continental targets. The V-2 could travel 225 miles and was 45 feet long. The rocket produced a thrust of 59,500 pounds at sea level and 70,000 pounds at altitudes above 25 miles. According to Willy Ley, the fuel for the V-2 "was ordinary ethyl alcohol to which enough water had been added to bring its strength down to 75 percent by volume." Liquid oxygen was used as the oxidizer. In the late 1940's and throughout the 1950's, V-2 rocket motor technology directly influenced plans for the development of missiles and rockets in the United States, and was considered to be the immediate ancestor for all US rocket technology.
Rocket experts at White Sands were anxious to exploit German V-2 rocket motor technology after World War II, and many projects were initiated. One of the original projects, the Hermes program was actually a conglomeration of different proposals. For a while, engineers proposed building a three-stage Hermes C rocket using six rocket motors in clusters of two in its first stage. These motors would be designed to develop a total of 600,000 pounds of thrust during a burning time of 1 minute. After jettisoning the first stage, the second-stage motors would provide an additional 100,000 pounds of thrust during a 1-minute burning time. The project itself was too ambitious and had to be cut back but the research material was handed over to Von Braun with instructions to create a 500-mile range rocket.
The 1950's
In the 1950’s the White Sands group was transferred to Huntsville, Alabama to continue working on these projects. After some failures, the Redstone NAA 75-110 was successfully fired. The Redstone was a redesigned V-2 rocket engine and could produce 78,000 pounds of thrust for 110 seconds. In May 1961 a Redstone engine was used to launch Alan Sheppard into space. On May 31, 1957, an Army Jupiter Intermediate-Range Ballistic Missile was fired to an altitude of 250 to 350 miles and to a range of 1,500 miles, marking the limit of its design capability and the first successful flight of such a missile. The success was tied to Huntsville where members of the Von Braun team had modified existing engine hardware to meet new requirements. Like the Redstone, the Jupiter missile drew power from a V-2. A thrust of 150,000 pounds was used for the Jupiter missile as opposed to the Redstone. The engine was also designed to operate on liquid oxygen and kerosene (RP-1), for the first time, instead of the liquid oxygen and ethyl alcohol used in the Redstone, resulting in a more efficient engine. The Jupiter space flight that probably attracted more public attention than any other came on May 28, 1959, when two primates, Able and Baker, rode in a capsule aboard a nose cone and survived the flight in spite of reentry temperatures of approximately 5,000 °F.
The 1960's
The Marshall Space Flight Center (MSFC) was dedicated on September 8, 1960 by President Eisenhower, where many of the researchers that formerly worked for the government were part of the core of the new NASA center. As the United States planned for the decade of the 1960's, a review demonstrated the clear need to develop a large-scale engine that could launch communications satellites and other scientific payloads, including weather satellites and instrumented probes. The engine was designed to eventually boost the Saturn launch vehicle. The history of the Saturn program began in the spring of 1957. In the late summer of 1958, MSFC was authorized to proceed with the design and development of a 1.5-million-pound thrust stage based on a cluster engine concept. The H-1 engine based on the Jupiter S-3D engine was selected for the new booster that would eventually be known as Saturn I. The design used Von Braun's clustering concept. This involved using former Redstone and Jupiter fuel tanks, which were lengthened to carry added propellant, while the basic diameter of the tanks were retained. The tank arrangement gave an alternate pattern of the four fuel and four oxidizer tanks, clustered around the 105-inch center oxidizer tank.
Rocketdyne was selected as the contractor to modify the S-3D designs for the H-1, which would also use liquid oxygen and RP-1, just as the Jupiter did. One of the largest innovations was the use of the rockets own fuel as a lubricant for the turbo machinery required to power it, instead of the formerly used oil tank that could cause contamination. Rocketdyne's Edward E. Straub also reviewed the modifications made to the H-1. Also, solid propellant was now used as an initial starter instead of the complex machinery once used. Initial versions of the Saturn I vehicle had eight H-1 engines-each producing 165,000 pounds of thrust. H-1 engines were also used in a later design that increased thrust to 188,000 pounds each. On July 30, 1965, the United States had clearly committed itself to President Kennedy's challenge to land a man on the Moon by the end of the decade, with the tenth launch of a Saturn I engine.
During the 1960's, most of the MSFC efforts were directed toward advanced engine technology and higher energy propellants. Cryogenic fuels appeared to be the way to go, with Liquid hydrogen as the leader in choice for the Saturn missions. Liquid hydrogen, however, introduced even more risk and danger into missile and space research. Engineers at Pratt & Whitney working on the RL-10 upper-stage rocket engine were introduced to hydrogen-fueled projects in 1956, with a sketch of the Hindenburg's last fateful moments and a report on an explosion of a hydrogen lab. Still the benefits of using such a fuel outweighed most other considerations. Studies showed that compared to an RP-1- fueled engine of similar size, liquid-hydrogen fuel could increase the specific impulse (see Specific Impulse) of an engine by 40 percent. The RL-10 engine was rooted in liquid-hydrogen engine research at Pratt & Whitney for the Air Force super-secret high-altitude reconnaissance aircraft known later as the "SR71 Blackbird." NASA eventually inherited responsibility for the RL-10 engine under development by Pratt & Whitney-and destined them for use in the Saturn I upper stages. The first flight of the engine occurred in 1964 after engineers at MSFC and Pratt & Whitney logged hours of engine testing in Huntsville and at other sites. The successful testing of these engines proved that liquid hydrogen was a viable source of fuel.
The final step to creating the Saturn V rocket, which would launch the highly successful missions to the moon, was the development of high power engines. The J-2 engine could develop 200,000 pounds of thrust and were derived from the RL-10 engines. Five of these engines were used in the Saturn V second stage to develop a thrust of 1,000,000 pounds. The next development was that of the F-1 engine. The F-1 engine was already in development in the late 50’s due to the foreseen need of an ultra high-power engine that could send probes into deep space. With John F. Kennedy’s challenge of sending men to the moon, the F-1 was finally realized. With a thrust capability of 1.5 million pounds, the five engines produced “double the amount of potential hydroelectric power that would be available at any given moment if all the moving waters of North America were channeled through turbines."
The 1970's - 1981
After Skylab was launched in 1973, the Space shuttle main engine was placed into development. The need for a compact engine with a much larger lift capacity was the goal of the HG-3 engine, as it became later known as. The primary concern with this engine was the development of extremely complex turbo machinery that could deliver the fuel at pressures several times greater than that of the Saturn rocket engines. One of the later innovations that came around was the placement of a computer on the engine to control operation and make corrective adjustments, or in emergency events safely shut the engine done. The HG-3 became the most advanced cryogenic liquid fuel rocket engine ever created. Finally on April 12, 1981 the first space shuttle was launched.
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