Thomas Frieling in Spaceflight

[carbon copy of this message being e-mailed to the man himself]

Hi, All..

Saw Thomas Frieling's piece in Spaceflight. Very nice!

No strong feelings either way on whether the shuttle should be ultimately
replaced by either a manned capsule or a small spaceplane, but this brings
up a question I've had in mind for a long time:

Would it be possible to build a reusable CAPSULE? Obviously, it would be
launched on an ELV and still have a disposable SM, but why not build a
series of capsules that can be used repeatedly and save a little money? The
reusability concept must have some validity to it!

Have a good one.

"Michael Gallagher" wrote:
Would it be possible to build a reusable CAPSULE?

Certainly.

Obviously, it would be launched on an ELV and still have a disposable SM,

And why are these obvious?

but why not build a series of capsules that can be used repeatedly and save
a little money?

Much depends on how much refurbishment is required between flights.
The big expense in reflight is all of the integration and testing.


The reusability concept must have some validity to it!

The problem is, the less you re-use, the less you save. Somewhere
along the spectrum between "full re-use" and "zero re-use" is the
balance point, but that point can shift with technology, engineering
tradeoffs, etc... for any given application.

D.
--
The STS-107 Columbia Loss FAQ can be found
at the following URLs:

Text-Only Version:
http://www.io.com/~o_m/columbia_loss_faq.html

Enhanced HTML Version:
http://www.io.com/~o_m/columbia_loss_faq_x.html

Corrections, comments, and additions should be
e-mailed to , as well as posted to
sci.space.history and sci.space.shuttle for
discussion.

Would it be possible to build a reusable CAPSULE? Obviously, it would be
launched on an ELV and still have a disposable SM, but why not build a
series of capsules that can be used repeatedly and save a little money?

Yes. During the transition period from shuttle to OSP the capsule and/or
service module can be brought back by a later shuttle flight. This would
require the item to be returned, most probably just the service module, to
be placed in a parking orbit accessible by the shuttle after the shuttle has
completed it primary mission.

Once the shuttle is retired a shuttle free reusable capsule is also
possible. If memory serves the Apollo capsules were intended to be
reusable, they were to "thump" down on land and be refurbished. Again, I
ma working from memory, each Apollo capsule could have bee flown up to five
times. Political posturing about whose congressional district the returning
heroes would thump down in led to NASA to switch to a water landing.
Strongly, being heated to several thousand degrees before taking a sal****er
dunk did nothing for the capsules reusability.

One of the primary arguments against a capsule is the need to mount a full
scale search and rescue effort every time one lands. The Navy billed NASA
through the noose for the use of its vessels and people. But, I have also
seen drawing and notes for a controlled landing by an advance Gemini capsule
using a fabric based, hang glider like Rollo wing. Putting the two together
and a reusable capsule is a very doable and much less expensive than many
make it out to be.

"gmw" wrote:
Once the shuttle is retired a shuttle free reusable capsule is also
possible. If memory serves the Apollo capsules were intended to be
reusable, they were to "thump" down on land and be refurbished.

Your memory fails. Gemini briefly was intended to come down on land
(under a parawing), but Apollo was targeted for a water landing from
the start.

Again, I ma working from memory, each Apollo capsule could have bee
flown up to five times. Political posturing about whose congressional district
the returning heroes would thump down in led to NASA to switch to a water landing.

Your memory fails. There never was any such thing considered.

Strongly, being heated to several thousand degrees before taking a sal****er
dunk did nothing for the capsules reusability.

Your knowledge fails. The interior of the capsule is exposed to
neither great heat, nor sal****er. The heatshield, which is so
exposed, would have to be replaced each time regardless of landing
mode.

One of the primary arguments against a capsule is the need to mount a full
scale search and rescue effort every time one lands.

Your knowledge fails. With few exceptions the capsules came down in
the intended area, and neither search nor rescue was required.

But, I have also seen drawing and notes for a controlled landing by an advance
Gemini capsule using a fabric based, hang glider like Rollo wing.

Your knowledge fails. That's the original intended landing mode for
Gemini, but the parawing was canceled when it had severe developmental
problems.

Putting the two together and a reusable capsule is a very doable
and much less expensive than many make it out to be.

That's an opinion, and a very debatable one at that.

D.
--
The STS-107 Columbia Loss FAQ can be found
at the following URLs:

Text-Only Version:
http://www.io.com/~o_m/columbia_loss_faq.html

Enhanced HTML Version:
http://www.io.com/~o_m/columbia_loss_faq_x.html

Corrections, comments, and additions should be
e-mailed to , as well as posted to
sci.space.history and sci.space.shuttle for
discussion.

Your memory fails. There never was any such thing considered.


Damm! How did I get so old?

gmw wrote:
Damm! How did I get so old?

Time.

In article ,
Derek Lyons wrote:
Your memory fails. Gemini briefly was intended to come down on land
(under a parawing), but Apollo was targeted for a water landing from
the start.

Nope. Not if you go back to the very start. The original Apollo specs
called for land touchdown in the continental US... not just for a nominal
flight, but for most abort cases as well (which was seriously hard).
Significant work was done on land touchdown before the requirement was
relaxed; you can find early Apollo papers on things like braking rockets
and landing-gear design.

(The *reason* for this requirement was the same as the reason why the
original specs called for totally autonomous navigation with no ground
assistance at all, not even a voice link: Cold War security jitters.)

Again, I ma working from memory, each Apollo capsule could have bee
flown up to five times...

Your memory fails. There never was any such thing considered.

Re-use of Apollo capsules was definitely *considered*, although by the
time hardware was actually flying, the idea had gone very much to the back
burner. Even so, the flight program did include one or two small test
objectives related to re-use.

Strongly, being heated to several thousand degrees before taking a sal****er
dunk did nothing for the capsules reusability.

Your knowledge fails. The interior of the capsule is exposed to
neither great heat, nor sal****er. The heatshield, which is so
exposed, would have to be replaced each time regardless of landing
mode.

Correct. As witness the successful reflight of one unmanned Gemini
capsule.

One of the primary arguments against a capsule is the need to mount a full
scale search and rescue effort every time one lands.

Your knowledge fails. With few exceptions the capsules came down in
the intended area, and neither search nor rescue was required.

Indeed, the landing precision was good enough that an operational system
could have landed just offshore, or even in a major lake, which would have
needed much less nautical infrastructure.
--
MOST launched 1015 EDT 30 June, separated 1046, | Henry Spencer
first ground-station pass 1651, all nominal! |

On Sat, 09 Aug 2003 21:12:38 GMT, "gmw" wrote:

..... I have also
seen drawing and notes for a controlled landing by an advance Gemini capsule
using a fabric based, hang glider like Rollo wing. Putting the two together
and a reusable capsule is a very doable and much less expensive than many
make it out to be.

Tom's article proposes that a revived CM would make a land landing
somewhere in the US southwest, cushioned by either retro rockets or
air bags. That should take care of the salt water problem!

"Michael Gallagher" wrote in message
...
[carbon copy of this message being e-mailed to the man himself]

Hi, All..

Saw Thomas Frieling's piece in Spaceflight. Very nice!

No strong feelings either way on whether the shuttle should be ultimately
replaced by either a manned capsule or a small spaceplane, but this brings
up a question I've had in mind for a long time:

Would it be possible to build a reusable CAPSULE? Obviously, it would be
launched on an ELV and still have a disposable SM, but why not build a
series of capsules that can be used repeatedly and save a little money?
The
reusability concept must have some validity to it!


It is certainly possible. The bigger question is whether it is cost
effective. According to a number of articles I've seen over the years, NASA
found that returned Apollo capsules were in surprisingly good condition, and
actually did give some thought to reuse. It was not pursued because of the
limited scope of the program and the adequate number of capsules
manufactured and available at the time. I have occasionally wondered if
Russia reuses any Soyuz components. They don't as far as I know, but I
have never seen it discussed one way or the other. One would think that a
certain amount of hardware (e.g. radios and the like) should be readily
reusable, regardless of the bigger issue of the capsule itself.

Well since I wrote the op-ed piece I'll add to this discussion.

1) Yes you can reuse Apollo type Command Modules.

Remember NASA launched Gemini 2, then gave it to the USAF who carved a
hatch in its heat shield, then re-launched it on the first and only
MOL flight. It was recovered in good shape and I believe is still on
display at the USAF Museum at the Cape.

But do you want to reuse the CM? I doubt it. For one thing if you, by
some miracle, got Congress to fund Apollo Redux, the contractor will
build five or ten, then shut the production line down. Then you start
losing them over time and you're in the same state NASA is in today
after losing 40% of its Shuttle fleet in two decades of flight: the
other side of the coin of reusability is "losability." Much better to
have the production lines open.

If NASA keeps flying Shuttles, some day they will run out of Shuttles.
Russia, on the other hand, just keeps building Soyuzes. We should have
followed their model: Even though they built a Shuttle, they never
discarded their Soyuz technology. If the US had kept Apollo CSM/Saturn
1B technology, we'd be a lot better off today than we are, waiting for
the Shuttle to return to flight.

Is it cost effective to reuse a CM? Who knows? But note that NASA goes
to a lot of trouble to recover and reuse the Shuttle SRBs even though
studies have determined it would be cheaper to throw them away.

I submit that NASA is chasing a chimera with reusability and would be
better off if it gave up on that notion.

2) You don't need Carrier Task Groups deployed for contingency
landings Even if your flying an Apollo type CSM. Does Russia deploy
Naval vessels for Soyuz? Heck no. You solve the contingency landing
zone problem by giving the craft sufficient on-orbit loiter time to
hit any landing zone. I prefer Kansas, or Edwards, but you also have
the vast steppes of Russia (where more than a few manned missions have
ended, right?) or even the Australian Outback if you needed it.

3) And you don't even need all that much open space. Apollo did have
some, albeit modest, cross range capability, since its center of
gravity was offset. Enough to avoid bad terrain on landing is all you
need. Plus, Apollo landings were very accurate. So land landings are
not a particular challenge.

4) Proponets of OSP "wings and wheels" approaches like to tout the
gentle low g reentry, supposedly so injured crewman will not suffer
adverse effects. But Apollo LEO reentries only pulled a little more
than three Gs max. I submit if a cremember is too ill to manage 3 gs,
he probably is beyond help.

And the one major advantage of reviving the manufacture of Apollo CM
vehicles is it opens the possibility of going back to the moon. You'll
never be able to justify the payload hit you'd suffer by hauling wings
and wheels all the way to the moon where they are of absolutely no
use. But once again having a CSM, you could at least entertain the
notion of going back.

Bottom line is: The next Shuttle disaster will be the last one. I am
sure the political fallout of losing another orbiter will surely end
the program.

So does NASA roll the dice every time it flies a Shuttle, hoping it
will return in one piece? Or does it get on with the task of replacing
it? If NASA does lose another Shuttle before a replacement is
operational, it will likely mean the end of US manned spaceflight.

As I said in the op-ed piece: Use the Shuttles to finish Space
Station construction, then retire the fleet. An updated Apollo CSM
then takes over crew rotation and an unmanned cargo carrier--a Jumbo
Progress vehicle--takes over logistics for resupply.

Then back to the moon....

"Phil A. Buster" wrote in message ...
"Michael Gallagher" wrote in message
...
[carbon copy of this message being e-mailed to the man himself]

Hi, All..

Saw Thomas Frieling's piece in Spaceflight. Very nice!

No strong feelings either way on whether the shuttle should be ultimately
replaced by either a manned capsule or a small spaceplane, but this brings
up a question I've had in mind for a long time:

Would it be possible to build a reusable CAPSULE? Obviously, it would be
launched on an ELV and still have a disposable SM, but why not build a
series of capsules that can be used repeatedly and save a little money?
The
reusability concept must have some validity to it!


It is certainly possible. The bigger question is whether it is cost
effective. According to a number of articles I've seen over the years, NASA
found that returned Apollo capsules were in surprisingly good condition, and
actually did give some thought to reuse. It was not pursued because of the
limited scope of the program and the adequate number of capsules
manufactured and available at the time. I have occasionally wondered if
Russia reuses any Soyuz components. They don't as far as I know, but I
have never seen it discussed one way or the other. One would think that a
certain amount of hardware (e.g. radios and the like) should be readily
reusable, regardless of the bigger issue of the capsule itself.