The Boeing version shows five NERVA-type rockets. Three at the base, and two stacked on top. But the Von Braun one apparently only had three. I'm not sure what was the last version. Was it the Von Braun one? Does anybody have more info on who was proposing what and when?
I'm reading (vol 2) 3 at the earth departure stage, 1 at mars deceleration and 1 at mars return.
I've been looking at the Boeing study and trying to figure out how it compares to the Von Braun "Integrated Plan."The Boeing version shows five NERVA-type rockets. Three at the base, and two stacked on top. But the Von Braun one apparently only had three. I'm not sure what was the last version. Was it the Von Braun one? Does anybody have more info on who was proposing what and when?
I think the difference in number of NERVAs was whether the Mars ship used lunar nuclear shuttles or purpose build NERVA tugs. The reasonning was to build a fleet of reusable nuclear shuttle for lunar missions to replace Apollo, and at a later date to borrow some tugs for a Mars shot. I think I red that in one of David Portree numerous blog entries, but can't remember where and when...
There's a colour version of Portree's monograph on NASA's website. So far as I know the text is the same as the one you linked here, but the grey-scale pictures are a bit easier to see since it's not a scan:http://history.nasa.gov/monograph21.pdf
Quote from: IRobot on 08/29/2012 03:38 pmI'm reading (vol 2) 3 at the earth departure stage, 1 at mars deceleration and 1 at mars return.Right, but my question was why the WvB plan only had three, whereas the Boeing one had five.I got a partial answer to my question here:https://falsesteps.wordpress.com/2012/08/08/mars-expedition-1969-nasas-waterloo/The author notes that in 1969 von Braun reduced the payload, which then made the vehicle a lot smaller (cutting it down from the five to three propulsion stages). I'm trying to get info on that proposal.
Okay, here's the Integrated Plan. The illustrations were contained separate from the report
In the 1966 JAG piloted flyby plan, the automated MSSR would land on Mars about two hours before the flyby craft flew past the planet and would immediately set to work gathering rock and soil samples using scoop, brush, sticky tape, drill, and suction collection devices. Less than two hours after MSSR touchdown, its ascent vehicle first stage would ignite. If all went well, the ascent vehicle's small third stage would deliver the samples to a point in space a few miles ahead of the flyby craft about 17 minutes later, 5 minutes after the flyby craft's closest Mars approach. As their craft overtook the sample package, the astronauts would snatch it in passing using a boom-mounted docking ring. They would then deposit it inside the Experiment Module's biology lab.
Osias noted that the NFSD contractors had recommended that no piloted spacecraft approach to within 100 miles of an operating NERVA I engine.
Von Braun described a Mars expedition "on the grand scale", with ten 4,000-ton ships and 70 crewmembers.