FH to the moon?

[M129K]

Here's a thought: Some of the Mars One art I've seen has shown Dragon-like hab modules daisy-chained all in a row. I know that Dragon is quite small but is there any reason why one or two couldn't be contrapted to act as a crew shelter? I'm thinking of a sleeping area and maybe relaxation area for an extended surface stay.

I know this all sounds needlessly elaborate but, if we're thinking of doing lunar surface using nothing but re-purposed FH and Dragon bits, something like this might be useful.

You could, but as you said, it would be small. There's only about 10m^3 of volume in a Dragon, and not all of that is habitable. However, judging from pictures of the interior, there's probably enough space for two beds and maybe a treadmill. It would be a lot more comfortable than the small, cramped lander.

[M129K]

That wasn't really what I was suggesting... but I think there is a potential huge advance on the horizon and sort of on topic:
F9R could potentially deliver propellant to orbit 100 times cheaper than today. We could refuel those massive second stages we are currently throwing away and use them as our earth departure stages. (add SEP and ISRU and you could refuel in lunar orbit and on the lunar surface as well, land the things on the moon and then send them all the way home to land propulsively on earth)

A Falcon 9R could deliver the Falcon 9 upper stage to orbit with maybe about 10 tons of propellant left over. If the upper stage can hold about 90 tons of propellant, you could get a fueled stage in orbit in 9 Falcon 9 launches, or two Falcon Heavy launches.

A fully fueled F9 upper stage could get about 32 tons into Low Lunar Orbit, and if you attach a set of landing legs, it can land about 10 tons down to the surface. That would make for a dangerously tall lander though, so I'd recommend against doing that.

[RigelFive]

I'm trying to think of any launch vehicle ever designed that just had all of this extra dial up "free" capability to allow flexible or modular mission planning to go to the moon or Mars.  Maybe the Russian/Soviet Universal Rocket UR-700 concept.  Not even SLS looks close to me for allowing LEO to Mars mission flexibility.  This spiral development philosophy makes everything 50x more expensive.

[AncientU]

I'm trying to think of any launch vehicle ever designed that just had all of this extra dial up "free" capability to allow flexible or modular mission planning to go to the moon or Mars.  Maybe the Russian/Soviet Universal Rocket UR-700 concept.  Not even SLS looks close to me for allowing LEO to Mars mission flexibility.  This spiral development philosophy makes everything 50x more expensive.

Spiral?

[Ben the Space Brit]

I'm trying to think of any launch vehicle ever designed that just had all of this extra dial up "free" capability to allow flexible or modular mission planning to go to the moon or Mars.  Maybe the Russian/Soviet Universal Rocket UR-700 concept.  Not even SLS looks close to me for allowing LEO to Mars mission flexibility.  This spiral development philosophy makes everything 50x more expensive.

The only thing that comes close (IMHO at least) is the Atlas-V Phase 2/3A, which scales from 25t IMLEO (crew launch) up to 105t IMLEO (five cores & heavy upper stage). I imagine that the HLV version has around 40t through TMI.

[sdsds]

I'm trying to think of any launch vehicle ever designed that just had all of this extra dial up "free" capability to allow flexible or modular mission planning to go to the moon or Mars.

Yes this is different (and exciting), particularly when compared with Apollo where everything was designed for a specific class of mission. The notion of flexible spacecraft mission modules or capability kits which allow the basic design to be used for multiple types of missions is driven by overall cost savings and a recognition of how high a percentage of costs are associated with design, development and test engineering, rather than manufacturing and operations per se.

This has an extra importance for FH/Dragon lunar missions. The Moon isn't a big part of SpaceX planning. But if all the pieces of the architecture (i.e. the mission kits or modules) were useful in other contexts, then with "spacecraft lego" they might be assembled into something lunar-capable. That's what allows a lunar mission "for free" (i.e. without designing any new lunar-specific modules).

In an earlier post I presented a picture of an extended duration Dragon kit that might enable lunar ascent. With this post I present another picture and another generally useful module (shown in green). This new module goes where the trunk would be in an ISS cargo Dragon. But it is a full-on propulsion stage with vacuum expansion nozzles on Draco-based engines. In the mission architecture I'm proposing, this stage would propel almost all of the lunar descent, being jettisoned a few hundred meters above the lunar surface. (After that, Dragon itself does the tiny but precise hovering descent portion.)

[KelvinZero]

Or perhaps the crasher stage could just be a drop tank? You have already solved the problem of having external fuel tanks for the ascent.
These super dracos must be enormously overpowered if they can be used for a LAS so I guess they are enough to support all that extra fuel going down. I guess it is not reasonable to simply include less of them, since there would then not be the same redundancy?.. Perhaps this redundancy is irrelevant on the moon where not getting to quite the right orbit is still a fail.
(rats, just saw the issue that then they would not be optimized for space, unless it was an in-space only dragon)

A fully fueled F9 upper stage could get about 32 tons into Low Lunar Orbit, and if you attach a set of landing legs, it can land about 10 tons down to the surface. That would make for a dangerously tall lander though, so I'd recommend against doing that.

I have always liked the idea of having the cargo around the base of a conventional-shaped rocket stage, so it is near the ground. This would be very stable re center of gravity especially when the tank is near empty. The legs could be on the cargo also, and left on the surface. Everything would be preassembled in earth orbit, including extending the legs.. one less thing to go wrong. There are a bunch of different ways of laying out the cargo and still keeping the center of mass above the engines. In the extreme, if the cargo is one large indivisible piece (and doesnt happen to be a donut), you could balance it with a smaller mass out on an arm. All those struts could get left on the surface just like the legs.

[TrevorMonty]

I haven't read this thread alway through so this may have been covered. Most thread talks about landings. In regards to fly by missions we know FH can send Dragon around moon and support a small crew for fhe trip but it would be bit cramp. To make trip more enjoyable and safer, why not add additional crew space. My thought was to use a modified Orbital Cygnus, something similar to  attached Mars mission concept.

members.marssociety.org/inspiration-mars/finalists/TIMEx.pdf

The plan would be to launch all modules on same FH, but stack it with Cygnus at bottom with propulsion module and Dragon at top. This would allow for launch abort by Dragon if needed. Once 2nd stage has done TLI Cygnus and Dragon would dock for rest of trip. Additional fuel in trunk may eliminate need for propulsion module. Additional life support in Cygnus would add cost but also redundancy and may allow for a crew of 7. Having to dispose of Cygnus at end of mission will add significantly to cost but will make trip a lot more pleasant and any extra crew would help pay for it. .

[Burninate]

If what you want is a direct 'flag & footprints' Lunar landing, then 5-ton Dragon, in its current form, is indeed borderline feasible - assuming that you fill its extended trunk with ~7 tons of propellant and a quad of moderate power high ISP engines for the 'return' stage (Falcon 9 launchable), then add a 'landing' stage with ~12 tons of propellant in it and landing legs (Falcon 9 launchable), then add a 'boost' stage with ~50 tons of propellant in it (Falcon Heavy launchable), and assemble these in orbit.  Boost stage is left to impact Luna on the early descent, landing stage is left on the surface or perhaps detaches during ascent.

A Lunar return mission costs surprisingly similar amounts of dV to a Mars return mission, if you treat aerobraking transitions as 'free'.

Mighty uncomfortable trip though, with scant payload for better living conditions, or science experiments.  No lunar rover to play with, no living quarters, no backup equipment.  The above also assumes you can get reasonable high-ISP vacuum-optimized engines.  More likely, you're stuck with lower ISP engines, need science and hab space, want a rover & dedicated airlock, Dragon Rider's LAS is going to add a decent number of tons, and then you end up with roughly similar mass fractions but split over *three* Falcon Heavy launches.

Stretch goal: Four or five Falcon Heavy launches will buy you a BA-330 on the surface of Luna (though not returned with DragonRider).

[docmordrid]

And why bother with that complexity when Musk has said they may do a lunar mission as a proof of capability, and the statement could be interpreted as meaning with a new launcher? Everything seems pointed towards an intermediate Raptor launcher well before the MCT launcher/vehicle.

[Burninate]

And why bother with that complexity when Musk has said they may do a lunar mission as a proof of capability, and the statement could be interpreted as meaning with a new launcher? Everything seems pointed towards an intermediate Raptor launcher well before the MCT launcher/vehicle.

A ~150T.LEO 9-raptor (which would indeed be useful here) and a ~500T.LEO 27-raptor (3 core Heavy) seem to be the options.