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  #51  
Old May 10th 05, 05:21 AM
Ed Kyle
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Pat Flannery wrote:
Ed Kyle wrote:


"http://yarchive.net/space/shuttle/launch_abort.html"


Oh, that's pleasant! Did they tell the crew about the little fire

problem?

I'm almost certain they did, since emergency crew
evacuation (slide wire and all) was being considered.
But the potential seriousness of the whole event was
understated so much that I'm not even sure the news
media picked up on it. The abort itself was news
enough, because it fed into the "shuttle isn't working
- NASA isn't able to get it off the ground - can't
meet schedule" story of the time. (Which turned into
the "NASA is too schedule-driven" story after
Challenger disentegrated.)

- Ed Kyle

  #52  
Old May 10th 05, 05:35 AM
Rand Simberg
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On Tue, 10 May 2005 09:19:45 +0800, in a place far, far away, "Neil
Gerace" made the phosphor on my monitor glow in
such a way as to indicate that:

" wrote in
message ups.com...

the DIV has to fly an odd trajectory (due to structural
concerns) that means that there are points in the ascent when abort is
*not* survivable.


Is that bad? Seems to me that it happens to STS as well.


Which is one of the several reasons that STS (to the surprise of many)
is not "human rated."
  #53  
Old May 10th 05, 05:41 AM
Pat Flannery
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Alan Anderson wrote:

Yes. So? A lot of launches is not a problem. It's a *goal*.



It leads to a lot of assembly in orbit, more expense due to having to
design the vehicle in smaller pieces, and greater odds one component
won't make it to orbit, botching the whole assembly process- then there
is the turn-around time of the launchpad to consider.
Their is also the problem of how to get all the parts successfully
rendezvoused and docked in orbit- each must have its own guidance and
RCS systems to bring everything together in one spot in orbit- that
means that the assembled multipart spacecraft will have excessive
guidance and RCS systems and their weight attached to it...or at least
carried with it into orbit, like the way the Soviet Kvant module was
brought to Mir via the jettisonable FGB space tug:
http://www.astronautix.com/craft/kvant.htm

Pat
  #54  
Old May 10th 05, 05:46 AM
Ed Kyle
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Pat Flannery wrote:
Ed Kyle wrote:

Kliper, proposed as a Soyuz replacement, but able to carry
up to six, is projected to weigh 13-15 tons, but its
propulsion system will not be recovered (Lockheed has
proposed to make the CEV hardware recoverable). NASA has
listed the maximum liftoff mass of CEV, including escape
systems and fairings that would not go into orbit, to
be 20 tons. CEV doesn't have to weigh that much, of
course.


Kliper was too heavy for a Soyuz booster, and was to use an uprated
Onega booster- a Soyuz booster with a new LOX/LH2 upper stage. This

was
later changed to the Zenit booster, which means you could

theoretically
launch Kliper from a modified Sealaunch pad.


It's about time Russia accepted Zenit for what it
is - maybe the world's most perfectly conceived
(if not perfectly executed) space launcher. It is
the rocket that NASA would like to have for CEV -
kind of like an Atlas V on steroids - able to boost
a 14-15ish ton payload to low earth orbit with no
solid booster augmentation. It is the capability
Russia is trying, unneccessarily, to copy with its
Angara program. China and Japan would like to have
such a rocket, but they don't. Europe had to work
hard to get its Zenit (Ariane 5G) working.

Ukraine and Russia have had the perfect machine
for nearly 20 years. They just haven't used it.

- Ed Kyle

  #55  
Old May 10th 05, 05:59 AM
Damon Hill
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"Ed Kyle" wrote in news:1115700375.069758.129750
@f14g2000cwb.googlegroups.com:

It's about time Russia accepted Zenit for what it

is - maybe the world's most perfectly conceived
(if not perfectly executed) space launcher. It is
the rocket that NASA would like to have for CEV -
kind of like an Atlas V on steroids - able to boost
a 14-15ish ton payload to low earth orbit with no
solid booster augmentation. It is the capability
Russia is trying, unneccessarily, to copy with its
Angara program. China and Japan would like to have
such a rocket, but they don't. Europe had to work
hard to get its Zenit (Ariane 5G) working.

Ukraine and Russia have had the perfect machine
for nearly 20 years. They just haven't used it.


The Zarya 'super-Soyuz' would have been a great complement.
The FSU blew its budget on Buran instead.

--Damon

  #56  
Old May 10th 05, 05:59 AM
Pat Flannery
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Ed Kyle wrote:

It's about time Russia accepted Zenit for what it
is - maybe the world's most perfectly conceived
(if not perfectly executed) space launcher. It is
the rocket that NASA would like to have for CEV -
kind of like an Atlas V on steroids - able to boost
a 14-15ish ton payload to low earth orbit with no
solid booster augmentation. It is the capability
Russia is trying, unneccessarily, to copy with its
Angara program. China and Japan would like to have
such a rocket, but they don't. Europe had to work
hard to get its Zenit (Ariane 5G) working.

Ukraine and Russia have had the perfect machine
for nearly 20 years. They just haven't used it.



I think it got sort of sidetracked when Energia went down the tubes,
followed by the Soviet Union going down the tubes.
It's a very impressive rocket looking for a very impressive payload to
carry.
Meanwhile, from far-off Hawaii, Jeffrey Bell looks at the CEV plan-
surprisingly, he doesn't like it ;-) :
http://www.spacedaily.com/news/oped-05zl.html

Pat
  #57  
Old May 10th 05, 06:22 AM
Rand Simberg
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On Tue, 10 May 2005 10:14:53 +0800, in a place far, far away, "Neil
Gerace" made the phosphor on my monitor glow in
such a way as to indicate that:

"Rand Simberg" wrote in message
.. .

Which is one of the several reasons that STS (to the surprise of many)
is not "human rated."


Well, it happens to airliners too. An abort (all engines out, no control
surfaces responding) is often not survivable. But they are still allowed to
fly.


Because, unlike a vehicle that has to be essentially rebuilt each
time, and only flies a few times a year (if that), they are reliable.
  #58  
Old May 10th 05, 06:58 AM
Scott Lowther
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Neil Gerace wrote:

" wrote in
message ups.com...



the DIV has to fly an odd trajectory (due to structural
concerns) that means that there are points in the ascent when abort is
*not* survivable.



Is that bad? Seems to me that it happens to STS as well.





From what I've been told, the thing is that if something goes goofy and
they hit the abort button, there are points in the launch trajectory
that result in the capsule (as that's what was assuemd at the time)
hitting the ground/water at unsurvivably high speed.

  #59  
Old May 10th 05, 09:37 AM
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How about hanging 2 shuttle SRBs on each side of a Delta IV core?
Launch on the solids only a la Titan 4, airstart the CBC at altitude
(ok some nozzle work required there). Maybe add one of the new higher
powered upper stages when (if) they come on line. For cargo only
flights of course, this combo has gotta have a decent throw weight.

Phil

  #60  
Old May 10th 05, 09:57 AM
Frank Scrooby
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Hi All


"Henry Spencer" wrote in message
...

BAe's Multi-Role Capsule design, done in the mid-80s, with a capacity
of four people for normal flight and six in a lifeboat configuration,
almost entirely reusable (including propulsion), had an estimated launch
mass of 8t including escape tower.


I seem to recall you've mentioned this (the BAe M-R capsule) before, Henry.

Do you have more info on this design?

The only reference I could get through Google is you:

http://www.spacebanter.com/q-t_5821-...aceflight.html

However, using some manual labor I found this:
http://www.astronautix.com/craft/mulpsule.htm ? Is this the beastie, you are
referring to, Henry?


Looking elsewhere on http://www.astronautix.com:

Apollo CM: (info copied from http://www.astronautix.com/craft/apollocm.htm.
Thanks Mark Wade!)

Crew Size: 3.
Maximum Diameter: 3.90 m.
Habitable Volume: 6.17 m3.
Mass: 5,806 kg (Structure Mass: 1,567 kg, Heat Shield Mass: 848 kg, Reaction
Control System: 400 kg, Recovery Equipment: 245 kg, Navigation Equipment:
505 kg, Telemetry Equipment: 200 kg, Electrical Equipment: 700 kg,
Communications Systems: 100 kg, Crew Seats and Provisions: 550 kg, Crew
mass: 216 kg, Miscellaneous Contingency: 200 kg, Environmental Control
System: 200 kg.)
RCS Coarse No x Thrust: 12 x42kgf.
RCS Propellants: N2O4/UDMH.
RCS Isp: 290 sec.
RCS Impulse: 26,178.00 kgf-sec.
Main Engine Propellants: n/a.
Main Engine Propellants: 75 kg.
L/D Hypersonic: .3.
Electrical System: Batteries.
Electric System: 20.0 kWh.
Battery: 1,000.0 Ah.

Now given that this is 1960s technology (and some of its was 1950s tech),
and given that the CM could apparently have accomodated 5 couches instead of
three if used purely for LEO ops, why is NASA even thinking about granting
contracts for a CEV?

I know this is not a new idea but why not just dust off the boilerplates and
blue prints for the CM? Scan the blue prints into an industrial CAD package.
Dismantle every piece of existing hardware that remains. X-ray it,
photograph it, measure it, wiegh it, do what ever you can to find out how to
reproduce it. Combine this data with the modernized CAD drawings. Use a
modern CNC machine to cut the majority of the parts, or to at least make the
templates.

Replace all the 1960s electronics, life support and reaction control with
1990s stuff. You can probably build in triple or quadruple redundancy, and
still end up using less mass and power than the original parts.

You can probably drop 25% of heat shield mass because the Apollo Mk2 doesn't
have return to the atmosphere directly from lunar orbit.

Use modern space-rated materials for the hull and structure. How light can
you make this thing?

Of cause the CM is almost useless without the SM, which according to
http://www.astronautix.com/craft/apollosm.htm has a mass of 24,523 kgs, but
18,413 of that is fuel for lunar orbit insertion. That is over six tons of
dry mass.

But the Gemini Adaptor- and Equipment- Modules only have a combined mass of
1868 kgs according to http://www.astronautix.com/craft/gemini.htm. Even if
this needs to be doubled for the Apollo Mk2, the vehicle would still come in
at less than 10,000 kgs for a five seater LEO crew delivery vehicle.

Has anyone got any figures on the Skylab Service Modules? I couldn't seem to
find them on http://www.astronautix.com/.

Rip out the seats and the life support and you got Apollo Mk2 'Progress
model' (you can drop the heat shielding too if you want to make it
disposable like the Russians did with Progress). Going with Apollo CM type
figures that would give you a vehicle with 6 cubic meters of cargo space,
and 2261 kgs of cargo space (if you're going for disposability 1093 kgs less
if you want to recover the capsule).

A new Apollo capsule should sit nicely on top of the Atlas V (with its five
meter maximum diameter fairing) and the Atlas van deliver 12,500 kgs to a
185 km orbit at 28.5 degrees (someone can tell me whether this is
ISS-compatiable).

The design is already proven, just update the parts you can't get anymore or
know you can safely replace with something better.

Fly it (unmanned, without the seats or heat shield , filled with cheap
disposable cargo) to ISS, as a proving exercise.

If it works, then fly a second one and try to recover it this time.

If that works risk a couple of volunteer astronauts on it.

I know reviving a 40 year old design is not as sexy (and probably not as
lucrative) as designing and building a new vehicle, but, at least, of late
the people who get paid to deliver the new vehicles have a poor record on
deliver (X-33). Maybe NASA should get its money back if its contractors fail
to perform ;-). Isn't that the way it works in the REAL WORLD.

Get ISS (and NASA) and alternative, safe and expandable crew and cargo
delivery system and then start thinking about how to extend it's usefulness
to lunar missions.

If you still need to do lunar missions once you've got this vehicle up and
running launch a lunar insertion stage seperately and do an on-orbit
rendezvous. If you need an LM, launch seperately and dock with that too.



--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |



Thanks and regards
Frank Scrooby



 




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