To the moon, naked and screaming...
Let's extend the idea of "naked and screaming" to a mission direct from Earth to the moon.
If all we cared about was getting a couple of people to the moon, alive, and we wanted to do it as cheaply as possible, we'd have a one-way rocket. It'd have no pressurized capsule. The astronauts would have space suits and a frame to strap into on top of a stack of rockets and fuel and some electronics.
Their vehicle would have a single, reliable engine and plenty of fuel tanks that can be ejected once empty. Since they don't want to land with a heavier engine than they really need, it's not a particularly large rocket. That may mean they take a bit longer getting to the moon - circling the earth an extra time or so for the most efficient engine burns. Same for the moon - an extra orbit or so - but they aren't going to take the time to establish a nice circular orbit either, as they aren't leaving a "return module" parked in orbit. It's already there, in case they can't land for some reason - a separate launch.
Once they land, they see their lunar hab waiting for them nearby - inflated at low "stand-by" pressure just to keep it from developing kinks that might start leaks. It's on it's own lander, which is otherwise identical to their own. It may have already been used by the last crew to land there - by now the CO2 has all be converted back to O2 using solar power - which is a good thing, as they only have about a day's emergency supply of air left with them. Time to power up the hab (they've got back-up fuel cells and H2 and of course their spare day of O2, in case something went wrong with the hab - even though the remote monitoring assured them everything was A-OK before they even launched. There's also an ascent module - another lander, with more fuel - sitting nearby.
So what did we really save by all that? Well, we essentially eliminated the weight of the lunar return module (yeah, we'll get back to that) and the hab module - probably about two-thirds to three-quarters of the "payload" - assuming you don't count the lander itself. They're the other one-third, of course. And even bigger, we've knocked off a mass of the "Command module" - 2x more than the original lunar excursion module. So - the total payload to the moon is about 1/3 of 1/3 - and with better equipment and no requirement to achieve circular orbit, we'll say we've shaved that to just 10% of the mass of the Apollo mission.
And that's good, because that puts the payload, plus fuel, down in the range that can launch on Ares I. And the hab can be launched on Ares 1. And so can the ascent module. (You didn't REALLY think we were going to just leave them there did you? Well, later on we will, of course...) And so can the return module waiting in orbit for the ascent module. And guess what's waiting in a convenient Earth orbit? Yep - descent module - a conventional re-entry capsule.
Huh - a whole lunar mission launched with Ares I, just because we broke it up into smaller pieces. Sure, it took us five launches - but we also had three- or four-fifths of our system already delivered in place and checked out before we launched our intrepid screamers. And because we didn't need Ares V, we didn't need a whole new launch facility, and the launch facility we had got used five times as much with the same people, which cuts per-launch costs at least in half, even if we didn't get a discount (which I would certainly demand) for buying Ares 1 in larger lots. That ought to be more than enough to make up for any higher efficiency Ares V might have offered. Not to mention - oh well, I guess I will - that we didn't have to pay to finish developing Ares V and testing it.
Sure, Ares 1 won't be rocketing us to Mars like Ares V would... Or will it...? If only we could find some liquid oxygen somewhere in space already, that'd cut our Mars launch mass... what else could we do to send some screams toward the red planet?
Let's extend the idea of "naked and screaming" to a mission direct from Earth to the moon.
If all we cared about was getting a couple of people to the moon, alive, and we wanted to do it as cheaply as possible, we'd have a one-way rocket. It'd have no pressurized capsule. The astronauts would have space suits and a frame to strap into on top of a stack of rockets and fuel and some electronics.
Their vehicle would have a single, reliable engine and plenty of fuel tanks that can be ejected once empty. Since they don't want to land with a heavier engine than they really need, it's not a particularly large rocket. That may mean they take a bit longer getting to the moon - circling the earth an extra time or so for the most efficient engine burns. Same for the moon - an extra orbit or so - but they aren't going to take the time to establish a nice circular orbit either, as they aren't leaving a "return module" parked in orbit. It's already there, in case they can't land for some reason - a separate launch.
Once they land, they see their lunar hab waiting for them nearby - inflated at low "stand-by" pressure just to keep it from developing kinks that might start leaks. It's on it's own lander, which is otherwise identical to their own. It may have already been used by the last crew to land there - by now the CO2 has all be converted back to O2 using solar power - which is a good thing, as they only have about a day's emergency supply of air left with them. Time to power up the hab (they've got back-up fuel cells and H2 and of course their spare day of O2, in case something went wrong with the hab - even though the remote monitoring assured them everything was A-OK before they even launched. There's also an ascent module - another lander, with more fuel - sitting nearby.
So what did we really save by all that? Well, we essentially eliminated the weight of the lunar return module (yeah, we'll get back to that) and the hab module - probably about two-thirds to three-quarters of the "payload" - assuming you don't count the lander itself. They're the other one-third, of course. And even bigger, we've knocked off a mass of the "Command module" - 2x more than the original lunar excursion module. So - the total payload to the moon is about 1/3 of 1/3 - and with better equipment and no requirement to achieve circular orbit, we'll say we've shaved that to just 10% of the mass of the Apollo mission.
And that's good, because that puts the payload, plus fuel, down in the range that can launch on Ares I. And the hab can be launched on Ares 1. And so can the ascent module. (You didn't REALLY think we were going to just leave them there did you? Well, later on we will, of course...) And so can the return module waiting in orbit for the ascent module. And guess what's waiting in a convenient Earth orbit? Yep - descent module - a conventional re-entry capsule.
Huh - a whole lunar mission launched with Ares I, just because we broke it up into smaller pieces. Sure, it took us five launches - but we also had three- or four-fifths of our system already delivered in place and checked out before we launched our intrepid screamers. And because we didn't need Ares V, we didn't need a whole new launch facility, and the launch facility we had got used five times as much with the same people, which cuts per-launch costs at least in half, even if we didn't get a discount (which I would certainly demand) for buying Ares 1 in larger lots. That ought to be more than enough to make up for any higher efficiency Ares V might have offered. Not to mention - oh well, I guess I will - that we didn't have to pay to finish developing Ares V and testing it.
Sure, Ares 1 won't be rocketing us to Mars like Ares V would... Or will it...? If only we could find some liquid oxygen somewhere in space already, that'd cut our Mars launch mass... what else could we do to send some screams toward the red planet?
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