As the Rocketdyne Mark IX turbopump tests at the B–1 Stand wound down in the spring of 1964, the Rocket Systems Division was making arrangements to modify the facility for the follow-up tests of the Aerojet Mark III pump.476 In April 1964, however, Lewis management decided to transfer the Mark III investigations to B–1’s new sister stand, B–3.477
The B–1 bootstrap tests had verified the analytical methods for calculating the startup characteristics of an axial-flow pump, but it was not demonstrated that these methods could be applied to centrifugal pumps.478 Although Aerojet had tested the pump extensively at its normal operating speed, there were no data for the low-speed realm. Certain issues only manifest themselves at lower velocities. The B–3 bootstrap tests of the Kiwi B–1B reactor and Mark III pump were designed to provide this information.479
The transfer of the test hardware from one stand to the other proceeded quickly, but it took another six months to work out the bugs of the new B–3 Stand. During this period the Rocket Systems Division installed a reheat system that returned the test hardware and its components to ambient temperatures immediately after the cryogenic test runs. This shortened the program by allowing two tests to be run in a single day.480 Meanwhile at the Nevada Test Site, a major test of the NERVA NRX engine took place in February 1966. It was the first time that all the NERVA engine components were integrated, albeit in a nonflightworthy arrangement. The test demonstrated that the engine could be bootstrapped and automatically controlled. It also proved that the reactor, turbopump, and other components could operate reliably in a range of conditions. SNPO Chief Harry Finger referred to it as, “the culmination of a long line of Rover research and development tasks.”481
The B–3 tests, which ran from March to December 1966, provided data on the Mark III pump’s operation at low speeds, its bootstrapping capability, and the system’s reaction to cryogenic temper- atures. The researchers found that the normal pump efficiency equations did not apply at low startup speeds, but the propellant flow characteristics did.482 The program was a success in another way, as well. Plum Brook engineers estimated that the $3,000 reheater shortened the estimated length of the program by three months and saved $50,000 worth of propellants.483
The Plum Brook staff overhauled the B–3 Stand to test the Kiwi B turbopumps in cavitating propellant conditions. As they were completing the final checkout runs in June 1966, Lewis management canceled the program.484 It is unclear why the effort was canceled, but it was likely due to lack of funding of the overall NERVA program.
Portent
In August 1964 Congress passed the Gulf of Tonkin resolution regarding Vietnam and the first of several pieces of War on Poverty legislation. The resulting Vietnam War and Great Society programs consumed large portions of the federal budget over the coming years. The introduction of these new expenses took place just as the new President, Lyndon Johnson, was asking NASA to identify postlunar landing roles for humans in space.
In response NASA began studying the feasibility of using Saturn and Apollo equipment to conduct a series of near-Earth missions that included proto-space stations, conversion of an Apollo capsule into a lunar base, and long-duration orbiting of the Earth and Moon. The proposal dimmed the prospects of human planetary exploration and the need for nuclear rockets. The budgets for both were cut in fiscal year 1965.485
In February 1965 NASA Marshall Space Flight Center researchers released a plan that would use several Saturn vehicles to launch a spaceship with humans on a flyby of Mars. That same month, however, the United States began bombing North Vietnam and preparing hundreds of thousands of troops for war. In addition, the Mariner 5 spacecraft sent the very first images of the Martian landscape back to Earth in July 1965. Not only was Mars barren but the spacecraft was exposed to greater levels of radiation than scientists had predicted. NASA’s fiscal year 1966 budget contained the Agency’s first decrease in funding ever. Although not traumatic, the cuts came primarily from the post-Apollo missions, while funding for the lunar landing remained steady.486
Image 109: Aerojet Mark III Turbopump. Several early missile systems used the Mark III, including the Navaho, Thor, Jupiter, Saturn I, and Saturn IB (NASA CD–10472–15).
Despite the cuts, NASA elevated its post-Apollo planning as funding for the Saturn rockets was coming to an end. The Agency created an Apollo Applications program office to study concepts for the future use of the Saturn, including an orbiting space laboratory that would become Skylab.487 In addition, the space science community gathered in the summer of 1965 to generate ideas for future space exploration, yielding 150 proposals for experiments that could be launched with Saturns.488
In 1966 NASA introduced an integrated post-Apollo plan that would use Saturn and Apollo hardware to create a space station over the next seven years and send robotic spacecraft on flybys of Mars and Venus in the early 1970s. This would be followed by human flybys in the late 1970s and the placement of humans on Mars in the 1980s. The Mars portions were referred to as Voyager.489 Despite these efforts, NASA’s fiscal year 1967 budget contained the Agency’s first major reduction. Again the post-Apollo missions, including Project Rover, bore the brunt of the reductions. The Vietnam War was escalating and civil unrest emerged in many U.S. cities.