Sixty-three days after the launch of Sputnik I, the world's first artificial satellite, and 30 days after the launch of 1118-pound Sputnik II with the dog Laika on board, the U.S. was at last ready. A Vanguard rocket stood on Launch Pad 18-A at Cape Canaveral, Florida, poised to boost a four-pound test satellite (nicknamed "the grapefruit") into space. The flight, designated TV-3, was intended as the first test of all three rocket stages of the 75-foot-tall Vanguard.
The countdown reached zero and the rocket's kerosene/liquid oxygen-fueled X-405 first-stage engine belched flame, lifting it a little more than a yard above the launch pad. Then the engine shut down and the Vanguard fell back onto Pad 18-A, rupturing its propellant tanks. The grapefruit bounced clear of the resulting fireball still transmitting its "beep-beep-beep" tracking signal.
President Dwight Eisenhower had agreed to fund Vanguard in 1955. The Second World War general and old-style Republican had no more use for space exploration than most presidents; rather, he was interested in keeping tabs on the military activities of the Soviet Union. His White House had become concerned that the Soviets might consider the passage of Earth-orbiting military surveillance satellites over their territory to be violation of their air space. Hence, Vanguard was conceived as a "civilian" program that would assert a new international legal principle - "freedom of space" - that would parallel the principle of freedom of the open seas. Once the new principle was established, the reasoning went, the Soviets would have less cause to object to surveillance satellites.
The Sputniks inadvertently asserted the freedom of space principle. According to one Defense Department official, the Soviets had done the U.S. "a good turn" by launching the first Earth satellites. Neither Eisenhower nor his advisors saw cause for alarm, but they misread the mood of the public. Some Democrats in Congress smelled blood; led by Senate Majority Leader Lyndon Baines Johnson, they berated the White House for being out of touch and for underfunding critical space technologies. Johnson led hearings that kept him in the public eye and earned him the nickname "Mr. Space."
The Vanguard TV-3 failure led to calls for more ambitious U.S. space projects, including robotic moon shots and men in space, with the aim of reestablishing U.S. technological primacy as rapidly as possible. The successful launch of the first U.S. satellite, Explorer 1, atop a modified U.S. Army Jupiter-C missile on January 31, 1958, further emboldened would-be space explorers. Explorer 1 carried a radiation detector borrowed from Vanguard. Data from the instrument led to the first major discovery of the space age: the existence of the Van Allen Radiation Belts. The discovery clearly demonstrated that satellites and probes could be used to conduct significant space science research.
Eisenhower, for his part, became more willing to fund U.S. space projects, but remained eager to avoid "glamour performances without a full appreciation of their great cost." He was also determined that space "stunts" and scientific exploration not be allowed to distract engineers from the serious business of developing missiles and surveillance satellites.
Partly because of this, Eisenhower supported calls for a civilian space agency to coordinate scientific space exploration and manned spaceflight. On 29 July 1958, after much negotiation with Johnson and other members of Congress, he signed into law the National Aeronautics and Space Act, which created the National Aeronautics and Space Administration (NASA). The civilian space agency, formed from National Advisory Council on Aeronautics (NACA) labs and space-related organizations within the Department of Defense, opened its doors for business on 1 October 1958, and initiated its first man-in-space program, Project Mercury, six days later.
The future of NASA remained murky, however, for Eisenhower did his best to quash talk of expansive space goals. He and his staff were especially critical of calls for men on the moon. This did not, however, prevent NASA engineers from planning manned lunar missions.
At the 10th International Astronautical Federation (IAF) Congress in London (31 August-5 September 1959), NASA engineers Milton Rosen and F. Carl Schwenk described a mission based on Direct Ascent, which they called "the simplest operational method" for a manned flight to the moon. Rosen, formerly Project Vanguard's technical director, had become Director of Launch Vehicles and Propulsion in the NASA Headquarters Office of Manned Space Flight in October 1958. Schwenk had become a NASA employee when Lewis Research Center, a long-established NACA lab in Cleveland, Ohio, joined the ranks of NASA facilities.
The two engineers told the IAF Congress that many in the space field in the U.S. foresaw more than a decade of increasingly complex robotic lunar missions before the first attempt at a manned moon mission. They dubbed this policy "instruments first - men later." Probes would hard-land on the moon's mysterious surface to measure radiation and perhaps return a few pictures, then lunar orbiters would map the surface in great detail to permit engineers and scientists to select landing sites for automated soft landers. These would at first remain parked where they landed, but later would rove over the surface. Only after that might NASA contemplate launching men to the moon.
Rosen and Schwenk argued that "we would learn much more at an earlier date by a bold and immediate approach to manned lunar exploration." This would, they admitted, entail increased risk to human lives. They noted, however, that developing robot explorers that could duplicate the exploration capabilities of men would be extremely costly and perhaps impossible. They told their IAF audience that it made good economic sense to explore the moon with humans at an early date rather than after a long and costly series of robots.
To launch their Direct Ascent mission, Rosen and Schwenk envisioned a 220-foot-tall Nova rocket with five stages. The first, measuring either 44 or 48 feet across (they used both numbers), would comprise a cluster of seven 16-foot-diameter cylindrical propellant tanks. The tanks would supply kerosene fuel and liquid oxygen oxidizer to six 1.5-million-pound-thrust F-1 rocket engines generating a total of nine million pounds of thrust (image at top of post). At first-stage ignition, the Rosen and Schwenk Nova would have a mass of 6.7 million pounds.
They envisioned launching their Nova from an equatorial Pacific island to avoid the orbital plane changes and launch timing issues of non-equatorial sites. Their first stage would burn for 135 seconds, boosting their rocket to an altitude of 35 miles. It then would shut down, separate, deploy a parachute, and splash into the sea, where it would be recovered for refurbishment and reuse.
The second stage, a cluster of four 16-foot-diameter tanks holding kerosene and liquid oxygen, would include a single F-1 engine. This would ignite immediately after first-stage separation and burn for 177 seconds, boosting the rocket to a speed of 15,800 feet per second. Stage 3, with a tank layout very similar to stage two, would then ignite its four 150,000-pound-thrust engines at an altitude of 150 miles. Rosen and Schwenk did not identify the third-stage engine type, though the H-1 was a likely candidate. The engines would burn "high-energy" liquid hydrogen and liquid oxygen propellants to place the fourth stage, fifth stage, and two-man crew capsule - which together would form the lunar spacecraft - on a direct 60-hour path to the moon.
The Nova's fourth stage, the descent stage for the lunar lander, would use high-energy propellants and four throttleable engines to achieve "the landing maneuver" at the end of a 60-hour voyage from Earth. Bearing the crew capsule and the fifth stage, it would alight on four splayed landing legs with a span of 40 feet.
Rosen and Schwenk described their Direct Ascent mission's conical crew capsule as "an enlarged version of the one used for Project Mercury." It would measure 12 feet across its base and 14 feet tall. Its lower level would contain crew couches, controls, and a "folding airlock" for access to the moon's surface. Its smaller upper level would hold food, electricity-generation systems, exploration gear, and work space.
A single rocket engine on the slender fifth stage - the lunar lander's ascent stage - would burn kerosene and liquid oxygen. The stage would nest at the center of the fourth stage, safe from meteoroids and the wide temperature swings expected on the moon. The fifth stage would attach to the center of the bowl-shaped heat shield at the crew capsule's base.
Rosen and Schwenk did not describe the 12-day lunar surface mission; they wrote that it would "be better described by those who have for years speculated about the lunar crust." When the time came to leave the moon, the astronauts would ignite the fifth-stage engine, which would burn for 220 seconds to launch the crew capsule on a direct 60-hour return path to Earth.
As they neared Earth, the crew would discard the spent fifth stage and carefully orient their capsule for atmosphere reentry. At an altitude of 30,000 feet, the capsule would deploy a single large parachute, under which it would descend to a gentle splashdown at sea.
Each Rosen and Schwenk moon landing mission would have used two identical Nova-launched lunar landers; the first would land on the moon unmanned ahead of the manned lander to provide a backup Earth-return capability. Both the unmanned and manned vehicles would descend to a landing guided by a homing signal from a pre-landed robotic soft-lander.
The authors acknowledged that Direct Ascent was not the only mode available for manned moon flight. Saturn rockets under development at the time they wrote their paper could, in theory, launch parts and propellants into Earth orbit, where they would be assembled into an Earth-orbit departure stage and a lunar spacecraft not unlike the one they proposed. They estimated, however, that each manned lunar landing would need eight successful Saturn launches, plus a separately launched assembly crew in Earth orbit. An unmanned test flight ahead of the first manned mission would require eight more successful Saturn launches. If a backup Earth-return spacecraft were desired, then the total number of successful Saturn launches for a single manned moon landing would come to 24.
Rosen and Schwenk judged this number to be impractical. They acknowledged, however, that flights including Earth-orbital assembly might be usefully combined with Direct Ascent flights in some space projects; for example, if a lunar base were established. In that case, assembly in Earth orbit might be employed to launch crews and Direct Ascent might be used to launch cargo. This approach had, incidentally, been suggested in the U.S. Army's June 1959 Project Horizon report, which called for establishment of a lunar fort in 1966.
The two NASA engineers ended their paper by touting the 1959 state of the art in rocket propulsion and asserting the feasibility (in terms of propulsion engineering, at least) of launching men to the moon.
References
"A Rocket for Manned Lunar Exploration," Milton W. Rosen and F. Carl Schwenk; paper presented at the 10th International Astronautical Federation Congress in London, U.K., 31 August-5 September 1959.
NASA's Origins and the Dawn of the Space Age, Monographs in Aerospace History #10, David S. F. Portree, NASA History Division, Washington, D.C., September 1998.
