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SAMU
2003-Apr-01, 08:39 PM
Since ICBMs have a demonstrated orbital rendezvous capability and the throw weight to lift several independent reentry vehicles inside of what is called a bus. How about making a few astronaut rescue reentry vehicle busses? To be stored at various ICBM sites to be mated to the ICBM booster and launched in the event astronauts need to be provided with alternate reentry resource. It should be cheeper, less complex and more reliable than maintaining and launching a shuttle in the event a rescue is needed.

daver
2003-Apr-01, 10:48 PM
I haven't heard of a demonstrated orbital rendezvous capability for ICBM's. Certainly for modified ICBM's (a good number of boosters started out as ICBM's). I don't see why ICBM's would need it.

I assume you're talking about something roughly on par with the Apollo Command Module. 5000 lbs. You'd need to equip the Command Module with a guidance system and a maneuvering system. A different docking system. You might want to figure some way of docking to the shuttle if the shuttle is tumbling, but that's going to be hairy. The Apollo capsule seated 3, but there were plans to add more seats for a rescue vehicle. I'm not sure there's much point in going smaller than Apollo--you lose a lot of flexibility.

5000 lbs is roughly on par with the payload of the Peacekeeper ICBM. You might need to launch two missions if the shuttle is fully loaded.

You'd probably want to make sure that all the devices (O2, scrubbers, maneuvering fuel, batteries) were relatively stable for long periods of time. That's not necessary--most likely you'd have a couple days to get things ready to go. But it still seems like a fairly reasonable tactic.

It would be nice to have the option of launching manned or unmanned. Launching manned would cut down significantly on the rescue capability, but it might be useful to have someone on the outside of the shuttle during the first stages of the rescue.

Note that this is starting to sound something like the orbital lifeboat--simple (capsule) reentry, long-term storage with little to no maintenance, 5-7 crew.

I'm not sure that instant response is all that useful--having a capsule in a central location and a transport aircraft to carry it to some appropriate launch site might e sufficient.

So. Developing a rescue/orbital lifeboat sounds like a good idea. Making it compatible with a Peacekeeper ICBM also seems reasonable. They should also be compatible with more conventional boosters. We should make a bunch of them, particularly if they can be desiigned for land recovery.

Colt
2003-Apr-02, 12:33 AM
I clicked yes because it would be possible with some changes to the warhead (mainly, take out the nuke :) ). As I write this I am constantly reminded of the Phoenix from ST: First Contact. If you replaced the warp drive section of that with a cabin it could probably carry 7 or 8 people. Of course that is no normal Titan ICBM which it uses, it is supposedy a Titan V (I think at least.. though they filmed a Titan II LV), something which has not been invented yet.

On to reality. First off, you would not be able to just have these capsules on standby in a normal ICBM silo. You would have to have dedicated launch sites. ICBM launch vehicles do not tend well to being transported around readily.

If we put one of these on a Peacekeeper (heh) it would probably be pretty long and not the short and stubby "bell" capsules of the early space program. I imagine that it would resemble a blunt bomb or a stubby artillery shell. Two people sitting side by side in rows, one pilot ("Press the big red button Sulu!") in the front. entry hatch through the top or nose.. -Colt

Colt
2003-Apr-02, 06:58 AM
InterContinental Ballistic Missile - Missile Rescue Pod MiRP

I did a quick thing in PSP7 of a possible design. It would be cramped and simple but it would get five people back safely. The MiRP (http://www.geocities.com/wandererofthewastes/MiRP.jpg). Kick it around a bit, I want your comments. -Colt

Colt
2003-Apr-03, 12:49 AM
*bump*

ToSeek
2003-May-02, 04:47 PM
Updated Apollo could replace lifeboat (http://www.floridatoday.com/news/space/stories/2003a/050203apollo.htm)

daver
2003-May-02, 09:59 PM
Updated Apollo could replace lifeboat (http://www.floridatoday.com/news/space/stories/2003a/050203apollo.htm)
There have been several proposals to use capsules as reentry vehicles. The main argument against them is medical emergencies--a space plane has lower g loads than a capsule (particularly on landing).

Frankly, i'd love to see a return to semi-ballistic reentry capsules--i think wings on a spaceship are silly.

Glom
2003-May-03, 02:04 AM
i think wings on a spaceship are silly.

What makes them silly? They allow a safer, more comfortable reentry. Of course they are abused in BA movies.

roidspop
2003-May-03, 03:00 AM
What makes them silly? They allow a safer, more comfortable reentry.

STS vs all of the ballistic capsules of the former Soviet Union and the United States; they may not have been comfortable, but they certainly have a much better safety record than the winged design.

Colt
2003-May-03, 03:57 AM
There were only what, 5, orbiters at any time and if you are going by percents that looks pretty bad but look at the number of missions versus missions.. Yeah, this coming from someone who believes firmly that the Orbiter is a brick with wings from the 80's. -Colt

daver
2003-May-05, 08:32 PM
What makes them silly? They allow a safer, more comfortable reentry.

STS vs all of the ballistic capsules of the former Soviet Union and the United States; they may not have been comfortable, but they certainly have a much better safety record than the winged design.

We've had one failure in one hundred odd missions of winged designs (the other shuttle failure had little to do with the winged design). There have been i believe two fatal accidents with capsule designs--one where the hatch didn't seal (which shouldn't be counted against the capsule) and one where the parachute lines tangled. The number of shuttle flights is roughly comparable to the number of capsule flights, their safety record is roughly comparable. We don't really have enough data to choose one over the other with regard to safety. Simplicity certainly favors the capsules. Comfort certainly favors the shuttles. Cost comparisons aren't valid because of the radically different designs of the two and because (at least for manned flights) capsules aren't reused.

Wingnut Ninja
2003-May-06, 12:41 AM
Would it be possible to put an unmanned lifeboat into orbit ahead of time, to keep it around just in case?

daver
2003-May-06, 01:41 AM
Would it be possible to put an unmanned lifeboat into orbit ahead of time, to keep it around just in case?
I believe Colt suggested manufacturing a number of unmanned lifeboats and launching one to rendezvous if a problem were detected. This seems a bit better--you don't waste a launch and clutter up an orbit if there's no need for the lifeboat. You don't have to worry about issues like on-orbit lifetime for the lifeboat. I expect that most of the time you'd be able to use the lifeboat you'd have several days to get it and an expendable ready (although as a matter of course if you adopted this strategy you'd always want an expendable stacked and ready whenever there was a manned mission).

Glom
2003-May-06, 12:23 PM
It's very convenient if you're spacecraft happens to collide with one of the lifeboats cluttering up orbital space. You won't have far to evacuate.