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Significant Navy program begun in 1946 to develop a single-stage-to-orbit satellite launch vehicle. The Air Force blocked Navy efforts to develop it on a joint basis, while at the same time having no interest in the project itself. Work was abandoned at the end of 1948.
Manufacturer: US Navy.
Version: Douglas HATV.
The Douglas HATV design of 1946 was laid out by the Douglas engineer William Ballhaus. He proved that there were no obstacles to a single-stage-to-orbit space launch vehicle, as long as pressurized 'metal balloon' tanks were used instead of using aircraft-structure design approaches. In July 1946, the US Army Air Force had concluded that a single-stage-to-orbit earth satellite was impossible based on a Rand Corporation report. The Office of Naval Research gave Douglas Aircraft manager Ed Heinemann a copy of the report. He in turn handed the report to Douglas scientist Dr. William F Ballhaus. Ballhaus was asked to visit Rand and verify the conclusions of the report. After visiting the Rand people, Ballhaus returned and concluded that the difficulty with the Rand designs were that they were all based upon conventional aircraft and missile structures. Ballhaus knew that a new approach was demanded. He realized that, if all critical structures were subjected only to tensile stresses, there would be no need for stringers, rings, or bulkheads, as in the conventional designs, and a significant amount of structural weight could be saved. He conceived of a steel balloon, pressurized when empty to support the payload, and further pressurized to accept the loads required for fuel and oxidizer during the entire flight to orbit. He designed a vehicle using this approach while assuming the same payload, propulsion, and control systems applied to the Rand designs. Detailed calculations were made regarding load factors, velocities, weight and drag. Ballhaus' conclusions were handed over to Heinemann and published as 'Preliminary Design of a Satellite', Douglas, El Segundo, Report ES 20636, on 7 August 1946. This was the first proof that a single stage earth satellite was indeed possible. However prior to publication Heinemann had the title page re-typed to remove "Prepared By William F Ballhaus" from the report. In his autobiography Heinemann claimed to have conceived the idea and took full credit for the study when introduced to Wernher von Braun in later years. Ballhaus noted that Heineman always bragged that he had only a high school education and yet he was able to manage a number of highly educated people. Heineman did not have the mathematical capability to analyze the critical aspects of the first single stage earth satellite, yet he claimed authorship of the design approach. In the post-war military cutbacks there were no funds for development of space launch vehicles. Ballhaus' 'metal balloon' concept would be later 'invented' again by Charles Bossart at Convair and applied to the Atlas rocket; and also by the German team in Russia in one alternative G-4 design. In his memoirs Heinemann takes full credit for the invention and mentions Ballhaus only as 'refining' Heinemann's 'rough calculations':
Shortly after World War II Dr Harvey Hall, a scientist with the Office of Naval Research, contacted me on a matter concerning satellites -- a subject treated with discretion because it dealt with the "unknown". Manufacturer: Douglas. Total Mass: 45,350 kg (99,970 lb). Core Diameter: 4.57 m (14.99 ft). Total Length: 27.40 m (89.80 ft).
Version: Martin HATV.
The Martin HATV 1946 design used a single Aerojet engine of unconventional design to achieve single-stage-to-orbit performance. The Glenn L Martin's company HATV design used a single enormous Aerojet liquid oxygen/hydrogen engine to achieve single-stage-to-orbit performance. The unconventional transpiration-cooled engine did not use a traditional convergent-divergent nozzle. Instead the cylindrical combustion chamber opened directly into a long conical nozzle. A permeable stainless steel inner liner cooled the walls using liquid hydrogen. Chamber pressure was 34 atmospheres, sea level specific impulse 310 seconds, and vacuum specific impulse 425 seconds. The design used integral oxygen and hydrogen tanks with a common bulkhead. V-2-type fins provided aerodynamic control at low speed. They would be jettisoned when they became ineffective, with jet vanes at the base of the expansion nozzle providing vehicle control thereafter. Magnesium was used in the nose compartment structure and steel in the nose cone. This 1946 design represented an early collaboration between Martin and Aerojet, which would be continued in the Titan series of rockets into the 21st Century. Manufacturer: Martin. Liftoff Thrust: 1,334.000 kN (299,895 lbf). Total Mass: 46,550 kg (102,620 lb). Core Diameter: 4.39 m (14.40 ft). Total Length: 23.50 m (77.00 ft).
Version: NAA HATV.
North American's HATV proposal was an ogival single-stage-to-orbit vehicle, with tanks made from 18-8 stainless steel. In common with other HATV designs, the tanks had to be pressurized to maintain rigidity. The tanks were pressurized via gas bottles in the engine compartment and not insulated. Instead insulation blankets shrouded the vehicle on the pad, and were jettisoned at lift-off. Propulsion was via a single central high-expansion ratio engine of 325 kN thrust, surrounded by eight low-expansion ratio engines of 127 kN thrust each. As propellant was exhausted and higher altitudes were reached, the low-expansion engines would be throttled back, allowing the more efficient, higher specific impulse central engine to provide most of the delta-V to orbit. The ascent profile involved flight to 90 km altitude, where the liquid engines would shut down. After coast to apogee half a world away, four small solid motors would fire to circulize the orbit at 280 km altitude. Two all-moving slab tailfins provided roll stability. Pitch and yaw control were provided by throttling the eight peripheral motors. The HATV components would be delivered horizontally by rail to the pad and stacked vertically using a gantry crane. Propellant during fuelling would also be delivered via tank cars by rail. The gantry would roll back for launch, and a water deluge would cool the pad to minimize damage during launch. Manufacturer: North American. to: 280 km Orbit. Liftoff Thrust: 1,034.000 kN (232,452 lbf). Total Mass: 45,350 kg (99,970 lb). Core Diameter: 4.02 m (13.18 ft). Total Length: 26.20 m (85.90 ft).
Version: World Circling Space Ship.
Rand study of 1946-1947, in response to the Navy HATV, for a three-stage satellite launcher to be in use by 1952. Development funding was not forthcoming. The US Navy's High Altitude Test Vehicle orbital launch vehicle design of spring 1946 brought about an immediate response - from the US Army Air Force, not the Soviets. It was considered vital for the USAAF to establish itself as the lead service in outer space. In April General Curtis LeMay asked the service's Project Rand think-tank to provide a comeback to the Navy on a crash basis. In just three weeks, sixteen Rand experts completed a 250-page engineering analysis of a "World-Circling Spaceship". Rand argued that "technology and experience have now reached the point where it is possible to design and construct craft which can penetrate the atmosphere and achieve sufficient velocity to become satellites of the earth." They stated that the USAAF could launch a 230-kg satellite into a 500-km orbit within five years at a cost of $150 million. In the report's introduction, Rand team leader David Griggs predicted: Though the crystal ball is cloudy, two things seem clear:The report's technical feasibility studies dealt with propulsion options, meteor strike risk assessments, trajectory analysis, and re-entry issues. In contrast to the Navy's single-stage-to-orbit HATV, Rand proposed a low-risk three-stage alcohol-oxygen rocket. Rand claimed it could identify no overwhelming technical challenges. The four-stage alcohol/liquid oxygen design would have a liftoff mass of 105,990 kg and a diameter of 4.0 m. A two-stage liquid oxygen/liquid hydrogen powered design would have a mass of 132,250 kg and a diameter of 6.3 m. However preliminary calculations for a three-stage liquid oxygen/liquid hydrogen design showed a launch mass of only 38,000 kg. These figures assumed aircraft-type fabrication techniques and no extraorrdinary weight-saving measures. The liquid oxygen/alcohol vehicle would have had a length of around 20 m. Radar expert Louis N Ridenour examined potential military satellite missions. A satellite would provide a nearly invulnerable observation platform that could provide weather and bomb damage assessment data. Satellites could serve as communications relay stations. He noted that a satellite positioned at an altitude of 38,000 km would be a motionless radio beacon in the sky, since its "rotational period would be the same as that of the earth". Potential scientific missions included cosmic rays studies, precise gravitational measurements, astronomy, and biomedical studies on the effects of zero-G on organisms. Satellites could be used to provide radio navigation data to long-range missiles. He finally noted that: There is little difference in design and performance between an intercontinental rocket missile and a satellite. Thus a rocket missile with a free space trajectory of 6,000 miles requires a minimum energy of launching which corresponds to an initial velocity of 4.4 miles per second, while a satellite requires 5.4 . Consequently, the development of a satellite will be directly applicable to the development of an intercontinental missile.Based on the Rand study, LeMay declined the Navy offer of a joint Navy-AAF satellite program at the May meeting of the Aeronautical Board. Instead he asserted the AAF's sole right to conduct American satellite operations . But despite the Rand report, the board members felt that satellites had questionable military utility. In that case the expense given could not be justified. However the Board agreed to permit both services to continue their studies. The issue of which would be responsible for the mission could be decided if it was ever decided to actually proceed with such systems. The Rand report established the technical feasibility of orbiting a satellite. But nuclear warheads of the period weighed four metric tons, twenty times the payload of the planned launch vehicle. LeMay himself was (and would remain) antagonistic to long-range missiles as a threat to his beloved fleet of manned bombers. And the project board was clearly not interested in a anything that did not have use as an offensive weapons system. In February 1947 Rand's James E Lipp produced a second, multi-volume study. It provided detailed specifications for a reconnaissance satellite system including a three-stage rocket booster with a gross weight of 37 metric tons, orbiting its payload at 560 km, and costing only $82 million to develop. Rand's analysis identified the need for fundamental research in such areas as guidance; orbital command, control, and communications; and reliable power sources. Solar power and miniaturized electronic equipment had not been developed at that time and were not considered. The report further explored the use of satellites for communications relay and included the first detailed analysis of the optical instrument requirements for a space-based reconnaissance satellite. Lipp noted that other nations would pursue satellite development and that: …the decision to carry through a satellite development is a matter of timing, depending upon whether this country can afford to wait an appreciable length of time before launching definite activity…The psychological effect of a satellite will in less dramatic fashion parallel that of the atom bomb. It will make possible an unspoken threat to every other nation that we can send a guided missile to any spot on earth … a satellite development program should be put in motion at the earliest time.But in the post-World War II budget environment, 'Buck Rogers' projects had no chance. The only American ICBM research program was cancelled in July 1947. In January 1948 USAF Chief of Staff Hoyt Vandenberg indicated that the USAF would continue satellite research efforts, but at a feasibility-study level only. The Navy attempted to join the Air Force again as a joint sponsor of the Rand project but failed to overcome the opposition of LeMay. By the end of 1948, the Navy "suspended" its satellite work and the American opportunity to orbit a satellite by the early 1950's was lost. Manufacturer: Rand. Core Diameter: 3.65 m (11.97 ft). Total Length: 20.00 m (65.00 ft). HATV Chronology 1947 October - Competing study contracts on satellites. Due to the number of competing study contracts on satellites that were being submitted, the Department of Defense assigned responsibility to coordinate this work to the Committee on Guided Missiles of the Research and Development Board. Bibliography:
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