Europe's Moon Shot

[Weaver]

Lunar Landing Vehicle: 20 tonnes (Apollo LM: 15 tonnes). Has a proper airlock so one of 3 crew can remain inside while 2 go EVA. Upper stage is ascent vehcle for return to lunar orbit.

...
RM burns Trans-Earth motor to leave lunar orbit. LOM is left in lunar orbit for potential re-use by next mission (it would need re-stocking, but all the science hardware and structure wouldn't need to be launched again.

I really like your idea. It nicely illustrates that it's possible to do a Moon mission with smaller launchers, but also the tradeoffs you have to make. Building 12 launchers for one mission isn't going to be cheap exactly.

Cheers.

NASA launched 10 Gemini missions in two years in the mid 1960s. Not quite the same thing, but it illustrates that big numbers are not neccessarily a disadvantage if you can get them big enough to achieve production-line status and economies of scale. As the saying goes, quantity has a quality all it's own.....

I'd want to add a rover. Preferably one that's a bit larger than the Apollo rover, and built so that it can be remotely operated: once the manned mission is over, the rover can be useful as an unmanned platform. Add some scientific instruments, and maybe have it collect rock samples that can be picked up on the next manned mission.

Oh, mine absoutely, definately has a decent rover: I just didn't mention it because I was concentrating on the flight scheduling more than the detail. I was going to suggest that it could be re-used by a subsequent mission, but then I realised that you probably wouldn't want to go to the same place twice. I LIKE the idea of making it a remote-controlled vehicle when the mission's over, although picking up the rocks means going to the same place twice again.

Here's an alternative: give the landing tean the rover and an instrument package; a sort of one-box science lab if you like. While they're there, they use the rover for personal transport and the instrument package statically. Before they leave however, they take the seats off the rover and replace them with the instrument package, thus making it into a remote-controlled mobile lab.

Leaving stuff in lunar orbit is an iffy proposition: the Lunar gravity field is so uneven that you need constant course adjustments to avoid crashing.

Didn't know that  - interesting...   Maybe with a bit of extra fuel you could use the Trans-Earth engine to boost it to a high orbit before leaving?

What was your idea behind the LOM? The combination of CM+RM+LOM seems overkill to me, but maybe I'm overlooking something?

Endurance mainly. The Crew Module has a 4-man re-entry capsule and a 6-way docking adaptor/airlock carved out of it's 20 tons, so it's not that big for 4 crew, and the Return Module has a big enough Trans-Earth engine and enough fuel to bring a 40-ton craft back. If you want to gain the advantages of a bigger ship it'd be a real shame to go straight there then come back again after a few hours, so by putting the science instruments, extra supplies and a bit more not-going-mad space in a third module, you gain a hell of a lot. For one immediate gain, you make the landing safer, because you can take a relatively long time to really scope out the proposed landing sites from a better vantage point than any of the mission planners on Earth.

[Old Wombat]

Oh, mine absoutely, definately has a decent rover: I just didn't mention it because I was concentrating on the flight scheduling more than the detail. I was going to suggest that it could be re-used by a subsequent mission, but then I realised that you probably wouldn't want to go to the same place twice. I LIKE the idea of making it a remote-controlled vehicle when the mission's over, although picking up the rocks means going to the same place twice again.

Here's an alternative: give the landing team the rover and an instrument package; a sort of one-box science lab if you like. While they're there, they use the rover for personal transport and the instrument package statically. Before they leave however, they take the seats off the rover and replace them with the instrument package, thus making it into a remote-controlled mobile lab.

There is also the option of giving it a solar/battery power plant & have it travel (slowly) from Landing Site A to Landing Site B... thus increasing your Lunar exploration coverage considerably.

[Weaver]

Oh, mine absoutely, definately has a decent rover: I just didn't mention it because I was concentrating on the flight scheduling more than the detail. I was going to suggest that it could be re-used by a subsequent mission, but then I realised that you probably wouldn't want to go to the same place twice. I LIKE the idea of making it a remote-controlled vehicle when the mission's over, although picking up the rocks means going to the same place twice again.

Here's an alternative: give the landing team the rover and an instrument package; a sort of one-box science lab if you like. While they're there, they use the rover for personal transport and the instrument package statically. Before they leave however, they take the seats off the rover and replace them with the instrument package, thus making it into a remote-controlled mobile lab.

There is also the option of giving it a solar/battery power plant & have it travel (slowly) from Landing Site A to Landing Site B... thus increasing your Lunar exploration coverage considerably.

Mmm - the Apollo landing sites were a pretty long way from each other. I guees it depends on how apart your landing sites are, how frequent your missions are, and how fast the rover can travel remotely. Remember that the real limit on rate of travel is the time delay between the rover's TV signal being sent and the resultant steering command coming back: if it's looking at gnarly terrain it can be a case of drive ten feet, wait five seconds, drive eight feet, wait five seconds etc... and that's not allowing for any debate at Mission Control about what to tell it. In the timeframe we're talking about, giving it any degree of artificial intelligence is probably right out of the question.

[Hobbes]

True. It should be possible to do an unmanned trip to pick up the samples, though. That can be a much smaller-scale mission (you're picking up maybe 100 kg of rocks, and you don't need life support so a small ship would suffice).

[Weaver]

Could be an "interesting" design exercise coming up with a system that can reliably transfer rock samples from a ROV to an unmanned lander without damaging it, unbalancing it or overloading it.....

[Hobbes]

I'd start with a well-defined way to collect samples. Using a hollow drill bit, you can gather a neat cylinder rather than a random lump. The samples can be stored in a box that has room for a number of those cylinders (in separate compartments to prevent sample contamination). You can weigh each sample, and keep track of the weight distribution in the box. Leave some space in the box where you can put ballast (more moon rock) if the weight distribution becomes too uneven.
Transfering the box to the lander is then a matter of lining up the rover with the lander.

BTW good point about the Return Module. The Apollo CM was rather cramped for a moon mission, with more space you can do some science while in Moon orbit and in transit too: you're outside the Van Allen belts, making the space environment rather different from LEO.

big numbers are not neccessarily a disadvantage if you can get them big enough to achieve production-line status and economies of scale.

That's true. I seem to remember a comment by SpaceX about exactly this. Of course their entire approach is centered on cutting cost, which includes economies of scale (see their reuse of the Merlin 1 engine for the Falcon 9). Can't find the quote right now, but IIRC building a handful of rockets per year is not enough for the workforce to become proficient: they have to figure out the best way to do things all over again. Once you're above a certain threshold (10-20?) there's no more learning curve, which really cuts the assembly time.

[Hobbes]

I've read Ministry of Space today. It has some interesting ideas (even if their execution in the book is rather unrealistic, but I won't go into that here).

1. Space planes. The US was working towards a space plane with the X-15 and Dynasoar. With current technology though, space planes only offer one advantage over ballistic capsules: a softer, more controllable landing. And that comes at a huge cost (extra weight that adds to the launch cost, a complex and more vulnerable heat shield). In this context it would have been nice to see some European experiments in this direction, some high-speed rocket planes, maybe some lifting body research craft.

2. A serious space station program. Using Weaver's ideas, a space station consisting of 20-ton modules can be put in orbit in a couple of years. MoS talks about using spent rocket stages, refitting them in orbit as part of the space station. That's doable (IIRC NASA studied doing this with the Shuttle external tank, it cost a couple of tons of payload to haul the tank up to orbit instead of dumping it), and would provide useful extra space, but can only be done if you already have the infrastructure to support major rebuilding in orbit.

3. a moonbase. That's more difficult, see Weaver's post on how many launches it takes to land a single mission on the moon. Long-stay missions on the moon also have radiation problems: you're outside the Van Allen belts, so no radiation shielding. Staying there for more than a week or two means you need heavy shielding, preferably by building your habitat underground.

[frank2056]

2. A serious space station program. Using Weaver's ideas, a space station consisting of 20-ton modules can be put in orbit in a couple of years. MoS talks about using spent rocket stages, refitting them in orbit as part of the space station.

Von Braun's idea of using inflatable modules to build a space station do work - Bigelow Aerospace has two inflatable (but unmanned) proof of concept spacecraft in orbit now.

[Weaver]

2. A serious space station program. Using Weaver's ideas, a space station consisting of 20-ton modules can be put in orbit in a couple of years. MoS talks about using spent rocket stages, refitting them in orbit as part of the space station.

Von Braun's idea of using inflatable modules to build a space station do work - Bigelow Aerospace has two inflatable (but unmanned) proof of concept spacecraft in orbit now.

Wow - didn't know about those: I'm impressed! 

[Weaver]

I've read Ministry of Space today. It has some interesting ideas (even if their execution in the book is rather unrealistic, but I won't go into that here).

1. Space planes. The US was working towards a space plane with the X-15 and Dynasoar. With current technology though, space planes only offer one advantage over ballistic capsules: a softer, more controllable landing. And that comes at a huge cost (extra weight that adds to the launch cost, a complex and more vulnerable heat shield). In this context it would have been nice to see some European experiments in this direction, some high-speed rocket planes, maybe some lifting body research craft.

There's another advantage to spaceplanes though, which Skylon demonstrates. If you build a spaceplane which has a relatively low density at re-entry, i.e. it's fuel tanks are internal and empty, then it gets slowed down quicker at higher altitudes, which greatly reduces the heat-profile of it's re-entry. Skylon doesn't need elaborate Shuttle-style thermal tiles because it's re-entry temperature is, IIRC, about half that of the Shuttle's, enabling it to get away with a much thinner ceramic skin with active cooling on selected high-heat areas.

This is an argument for actually keeping MORE of your rocket. Instead of having a small, dense spaceplane like Dynasoar as the payload at the top of a third stage, it would make more sense to incorporate that third stage into the spaceplane to get it's density-reducing advantages at re-entry. If you're third stage was powered by an LOX/Kerosene rocket, then you could store the kerosene in the wings, thus enabling the fuselage, with it's LOX pressure vessel, to be made smaller, thus minimising the structural cost. Another advantage of using kerosene would be that you could make the spaceplane self-redeployable by using "clip-on" tubrofans to turn it into a conventional aircraft running on a fraction of the kerosene tankage. This means that you could land it anywhere and then just fly it home, following a visit by a transport aircraft with the turbofan packs.

[Hobbes]

Interesting. I wonder what that would mean for the size of the launcher, though. An alternative history where HOTOL succeeds would be worth exploring.

The clip-on turbofans remind me of the Buran Analog (OK-GLI), where they stuck a couple of turbofans (from a Su-27, iirc) on the airframe for flight tests:




Inflatable modules are nice, but they don't solve the hardest problem in spaceflight: rocket launches are limited more by weight than by volume. Inflatables give you extra volume, but not the fixings and fittings, meaning they're probably more suited for hotels (and crew quarters) than for workshops.

[Hobbes]

I've been going through old threads at Secretprojects, and found some gems that relate to this.

There was an actual study for an European moon program from a few years ago, based on an Ariane 5 with 6 boosters and some other mods to allow it to launch 50 tons:
http://spaceflight.esa.int/strategy/pages/PDF/home/events/integrated_architecture_review/8_July/06.%20Moon-scenario-1.pdf

Also in that thread, a bunch of studies for heavier launch vehicles than Ariane 5:
http://www.secretprojects.co.uk/forum/index.php/topic,1511.0.html

[James]

Oooh, I've just had a vision that's better than Viagra - a Vulcan converted to a space shuttle.

Yeah, British aircraft in space!

What about Buccs? They were made from solid blocks of metal and are that tough the Earths atmosphere would probably just give in and let them re-enter.

Saro SR.177! How many of the OR F.155 look like they belong in space; the Saro P.187, Vickers-Armstrong Type 559, AW.169!

[Weaver]

Oooh, I've just had a vision that's better than Viagra - a Vulcan converted to a space shuttle.

Yeah, British aircraft in space!

What about Buccs? They were made from solid blocks of metal and are that tough the Earths atmosphere would probably just give in and let them re-enter.

Saro SR.177! How many of the OR F.155 look like they belong in space; the Saro P.187, Vickers-Armstrong Type 559, AW.169!

Or the Avro 730 for that matter.....

[Mossie]

The Europa project was abandoned, but its first stage (derived from the Blue Streak ballistic missile project) performed well.

If the Europa project had succeeded, a logical next step would be a larger rocket, using maybe 4-5 RZ2 engines in the first stage. Similarly to Ariane, strap-on boosters could be added, weight to LEO maybe 7.5 -10 tons. The next step up would be a new first stage and larger boosters to get 20t to LEO. With more funding, this could have happened by the early '80s.

Harro mentioned a version of Europa using a Blue Streak first stage with strap on boosters.  There were a few versions mooted, solid boosters for a 310-360kg payload, liquid  boosters for 600-700kg payload.
http://www.spaceuk.org/bstreak/eldo/augmented.html

Europa with solid boosters:


Also a version with a Centaur upper stage & up to four strap on boosters giving a 1 tonne payload.  This would have meant co-operation with the USA, the French probably wouldn't have been happy about that.
http://www.spaceuk.org/bstreak/bs/bs_centaur.html

A Bristol Siddlely alternative to Black Arrow that would have been more advanced & capable of lifting a much greater payload.  Might have been capable of lofting a decent paload with a Blue Streak first stage & boosters.  It wasn't really affordable, but co-operation with Europe might have made it so:
http://www.spaceuk.org/ba/siddeley.htm

Space UK is a very useful site, it's by Nicholas Hill who authored A Vertical Empire, a fair bit of info on UK launcher projects & proposals:
http://www.spaceuk.org/index.htm

PS, Harro, thanks for the heads up on the new edition of A Vertical Empire, I nearly bought the first edition but I'll hold on.