Boeing Manned Interplanetary Spacecraft Boeing's 582-foot nuclear-thermal spacecraft is probably the best-known conceptual Mars vehicle of the 1960s. At Earth-orbit departure, it would include a 108-foot-long, 140.5-ton piloted spacecraft and a 474-foot-long propulsion section made up of five Primary Propulsion Modules (PPMs). The six-person piloted spacecraft would comprise a MEM, a four-deck Mission Module, and an Apollo Command Module-derived EEM. Each 33-foot-diameter, 158-foot-long PPM would hold 192.5 tons of liquid hydrogen. A 195,000-pound-thrust NERVA engine with an engine bell 13.5 feet in diameter would form the aft 40 feet of each PPM. The entire spacecraft would have a mass just prior to Earth-orbit departure of between 1000 and 2000 tons, the exact figure being dependent upon the energy demands of the Earth-Mars-Earth transfer opportunity used. Three PPMs would make up Propulsion Module-1 (PM-1), and PM-2 and PM-3 would comprise one PPM each. PM-1 would push the ship out of Earth orbit toward Mars, then detach, PM-2 would slow the ship so Mars's gravity could capture it into orbit, then detach, and PM-3 would push the ship out of Mars orbit toward Earth. At Earth, the crew would separate in the EEM, reenter the atmosphere, and splash down at sea. Six uprated Saturn V rockets would launch parts and propellants for Boeing's ship into Earth orbit. The 470-foot-tall Saturn V variant, with four solid-propellant strap-on rockets, would be capable of launching up to 274 tons into a 262-mile-high orbit. Boeing envisioned that NASA would modify pads 39A and 39B for the uprated Saturn V and would build a new Pad 39C north of the existing pads. Assembly crews and the mission crew would reach the spacecraft in Apollo Command and Service Module (CSM) spacecraft launched on Saturn IB rockets. Boeing's report listed 15 opportunities for Mars missions between November 1978 and January 1998. These would include one conjunction-class mission comprising two relatively short interplanetary transfers separated by a long stay at Mars and five opposition-class missions comprising a relatively short transfer and a relatively long transfer separated by a short stay at Mars. Nine other opportunities would include Venus swing-bys; these would use the planet's gravity to slow the spacecraft's approach to Earth, trimming EEM reentry speed. The conjunction-class mission would last a total of 900 days, while the opposition-class and Venus swing-by missions would last from 460 to 680 days. North American Rockwell (NAR), makers of the Apollo CSM, designed the MEM for Boeing's mission on contract to the Manned Spacecraft Center in Houston between October 1966 and August 1967. NAR's was the first detailed MEM design to incorporate the Mariner IV results. Boeing scheduled its first Mars mission for 1985-1986, with spacecraft contract awards in 1976, and tests in low-Earth orbit beginning in 1978. NAR placed development cost of its MEM at $4.1 billion, while Boeing's study placed total Mars program cost at $29 billion.

Nicely detailed. What should have been (sigh)

Excellent presentations! Thanks for including the diagrams. That's a very clever MEM design.

Awesome! Corrie

Terrific work. It's a terrible pity this can only be classed as "science fiction". A few years ago I did some work colouring Syd Jordan's Hal Starr story for publication in Spaceship Away mag. (Syd is famous for his earlier Jeff Hawke newspaper strip). The Hal Starr story featured a desion of the NERVA concept - but with nowhere near the detail you have produced.

Thanks geirla -- Bambam had asked about features of the MEM -- and a little more digging unearthed more complete diagrams -- so I wanted to include them. This also gives some idea of what the source material I work from looks like -- I am blending the look and feel of actual NASA hardware with research into engineering specs for never constructed hardware -- to yield a projection of what these craft might have looked like had they been constructed.

Thanks JohnRidgway,and you make an excellent, if somewhat painful, point. The present state of America's space program is a tragedy which both saddens and angers me. NASA plans for NERVA included a visit to Mars by 1978 and a permanent lunar base by 1981. Under the Integrated Program Plan NERVA rockets would have been used for nuclear "tugs" designed to take payloads from Low Earth Orbit to higher orbits – it is a nearly forgotten fact that NERVA was intended as a component of the Space Shuttle Space Transportation System, permitting not merely one space station at LEO, but economic resupply of several space stations in various orbits around the Earth and Moon, and support of a permanent lunar base. Few today really know how truncated the STS system became with Congress voting to reduce and cut many components including shuttle-derived heavy launch vehicles. Full development would have seen NERVA used first as a nuclear-powered upper stage for the Saturn rocket (the Saturn S-N), which would allow the up-rated Saturn to launch much larger payloads of up to 340,000 pounds to Low Earth Orbit. In hardware test stands NERVA rockets progressed rapidly to the point where they could run for hours, limited in run time by the size of the liquid hydrogen propellant tanks at the Jackass Flats test site. They also climbed in power density. NERVA NRX operated for nearly 2 hours, including 28 minutes at full power. The second NERVA engine, the NERVA XE, was designed to come as close as possible to a complete flight system, even to the point of using a flight-design turbo pump. Total run time was 115 minutes, including 28 full re-starts. NASA and SNPO --the Space Nuclear Propulsion Office -- felt that the test "confirmed that a nuclear rocket engine was suitable for space flight application and was able to operate at a specific impulse twice that of chemical rocket system.” The engine was deemed adequate for Mars missions being planned by NASA. The facility was also deemed adequate for flight qualification and acceptance of rocket engines from the two contractors. The RIFT (Reactor In Flight Test) vehicle consisted of a Saturn S-IC first stage, an S-II stage and an S-N (Saturn-Nuclear) third stage. The Space Nuclear Propulsion Office planned to build ten RIFT vehicles, six for ground tests and four for flight tests. The nuclear Saturn C-5 would carry two to three times more payload into space than the chemical version, enough to easily loft 340,000 pound space stations and replenish orbital propellant depots. Wernher von Braun also proposed a manned Mars mission using NERVA and a spinning donut-shaped spacecraft to simulate gravity. Many of the NASA plans for Mars in the 1960s and early 1970s used the NERVA rocket specifically. RIFT was delayed after 1966 as NERVA became a political proxy in the debate over a Mars mission. Hobbled by lack of insight and imagination, members of Congress in both political parties suffered what I would term a “failure of vision”-- able to see manned space flight as a mere manifestation of the Cold War U.S./Soviet competition -- these bureaucratic functionaries deemed that a manned mission to Mars would represent a tacit commitment for the United States to open-ended decades of the expensive Space Race – and many eyed the NERVA – and the entire NASA manned space-flight program budget, with envy. Manned missions to Mars and the outer planets were enabled by nuclear rockets; therefore, if NERVA could be discontinued the Space Race might wind down and vast funding streams could be diverted. RIFT was delayed and the goals for NERVA were set higher – and despite its successes, in the end program implementation was never authorized. The post Apollo Integrated Program Plan was abandoned, the STS program was gutted by failure to fund HLLV and the successor vehicles required to replace the aging Space Shuttle. Those who have been paying attention will recognize the obvious tactical and strategic actions in terms of the Obama Administration’s “targeted defocusing” of NASA. What do I mean by “target defocusing?” Targeted defocusing is intentional sabotage with the objective to prevent accomplishment of achievable goals, it is diversion of resources, talent, and skill from work of value, turning the potential for success into a certainty of failure – failure which can be later pointed to and used in justification of abandonment. Cutting Constellation, after extensive development, and calling for missions to near-earth asteroids (which would actually require manned Mars mission capabilities)is targeted defocusing. Defusing NASA’s mission objectives and goals with political-correctness and Leftist social feel-do-goodery is targeted defocusing. It’s the money that they are after folks – and in the case of Obama and the Left, the diversion into wealth distribution schemes and crony-capitalism is an act of theft (yes, I do mean theft) that will lead to no profitable result for America or mankind, and while a committed space program comes at expense, it also delivers measurable advances and value – and, finally, I ask you, at what cost do we sacrifice the future?

These are splendid renderings of what might have been. As much as I wish this technology and capability had been developed, I am pleased by more recent developments that are largely being driven by people outside the current bureaucracy and politics-driven government funding. We may yet see something like this eventually happen, but from private/public cooperative efforts which could put critical portions of outside the vagaries of politics and the never-ending campaign loops we're caught in these days. Add to that the promising researches into very unorthodox nuclear and fusion research, things like VASIMR, not to mention SpaceX and such, and things are starting to look promising once again. The real shame is to imagine what NASA could have done with the money that was spent on developing the B-1 bomber? But, like I said, I see reason for hope, and seeing your brilliant work on these designs that really only barely got past the description-phase is incredibly impressive and inspiring!

NefariousDrO, Your insight and continued contributions and comments mean alot to me -- I am always pleased to read your input, thank you! You raise excellent points, being an Objectivist philosophically I share your convictions regarding the need for private sector development of a space based infrastructure -- and it is certainly true that the future lies purely in the hands of private and free individual and corporate investment. It is a sad truth that history is not handled in an entirely factual manner in this regards: the original colonies on these shores were founded by private corporate investment, these were the New England venture capitalist colonies -- yes there were ideological and religious colonies but these were the minority rather than the majority. If we are ever to see man take his place, fulfilling his nature and his role as a creature of exploration and innovation -- it is private venture capital which will sustain the effort.

I really love these presentations, very impressive work as always!!! Cheers, David

fantastic work!