CEV history
Pat Flannery
about the history and contenders for the CEV design:
http://www.astronautix.com/craftfam/cev.htm
The final Lockheed design looked like a Soyuz A:
http://www.astronautix.com/graphics/z/zcevlocm.jpg
http://www.astronautix.com/craft/soyuza.htm
Pat
Brian Thorn
wrote:
Another EA opportunity to dump on the US, I see. Has Wade ever made a
positive comment about NASA?
Why he's fixating on the "superiority" of Soyuz's three-module
arrangement (again) is baffling. Constellation won't need a third
module. We already have a Space Station, so we don't need a
Shenzhou-like mini-lab at the top of CEV. For moon flights, there will
be an LSAM attached up there, so the third module would be redundant,
especially with the CEV being unmanned during lunar landings. Cargo to
ISS is supposed to be launched separately, and CEV's one-module
internal volume is about the same as Soyuz's anyway.
Wade carries on about how NASA is "making the same mistake as Apollo"
(almost as if Apollo lost the moon race) but nowhere in his anti-US
tirade does he explain why NASA's CEV design is bad. He just wants us
to take it on faith (and that seems to be true, literally) that
anything coming out of NASA must, by default, be wrong.
Brian
Pat Flannery
Brian Thorn wrote:
>
>Another EA opportunity to dump on the US, I see. Has Wade ever made a
>positive comment about NASA?
>
>Why he's fixating on the "superiority" of Soyuz's three-module
>arrangement (again) is baffling.
>
A lot of the U.S. contenders apparently took the three-module approach
quite seriously looking at the various drawings shown.
> Constellation won't need a third
>module. We already have a Space Station, so we don't need a
>Shenzhou-like mini-lab at the top of CEV. For moon flights, there will
>be an LSAM attached up there, so the third module would be redundant,
>especially with the CEV being unmanned during lunar landings. Cargo to
>ISS is supposed to be launched separately, and CEV's one-module
>internal volume is about the same as Soyuz's anyway.
>
>Wade carries on about how NASA is "making the same mistake as Apollo"
>(almost as if Apollo lost the moon race) but nowhere in his anti-US
>tirade does he explain why NASA's CEV design is bad. He just wants us
>to take it on faith (and that seems to be true, literally) that
>anything coming out of NASA must, by default, be wrong.
>
>
I think that the current CEV design is awfully conservative in the
design department, but that might be a good thing all-in-all.
Pat
Rand Simberg
Thorn <btho...@cox.net> made the phosphor on my monitor glow in such
a way as to indicate that:
>Wade carries on about how NASA is "making the same mistake as Apollo"
>(almost as if Apollo lost the moon race) but nowhere in his anti-US
>tirade does he explain why NASA's CEV design is bad.
Because while it won the moon race (which was its primary purpose) it
won't be any more affordable or sustainable than Apollo was.
Henry Spencer
Brian Thorn <btho...@cox.net> wrote:
>Wade carries on about how NASA is "making the same mistake as Apollo"
>(almost as if Apollo lost the moon race) but nowhere in his anti-US
While he may not be expressing it well, there's a real problem there.
Apollo's design wasn't a bad one, given its limited political objectives
(which did include haste and didn't include graceful expansion for more
ambitious missions). The mistake is to repeat it, when its job was done
thirty years ago and doesn't need re-doing.
The CEV design is, as has often been said, "Apollo on steroids"... and
that's *all* it is. Its basic mission profile -- LOR with an expendable
spacecraft -- is optimized for occasional short visits on a generous
budget. This is not a good way to start a "back to stay" project.
--
spsystems.net is temporarily off the air; | Henry Spencer
mail to henry at zoo.utoronto.ca instead. | he...@spsystems.net
Will McLean
Henry Spencer wrote:
> In article <ffdcu1lius41cd565...@4ax.com>,
> Brian Thorn <btho...@cox.net> wrote:
> >Wade carries on about how NASA is "making the same mistake as Apollo"
> >(almost as if Apollo lost the moon race) but nowhere in his anti-US
> >tirade does he explain why NASA's CEV design is bad...
>
> While he may not be expressing it well, there's a real problem there.
> Apollo's design wasn't a bad one, given its limited political objectives
> (which did include haste and didn't include graceful expansion for more
> ambitious missions). The mistake is to repeat it, when its job was done
> thirty years ago and doesn't need re-doing.
>
> The CEV design is, as has often been said, "Apollo on steroids"... and
> that's *all* it is. Its basic mission profile -- LOR with an expendable
> spacecraft -- is optimized for occasional short visits on a generous
> budget. This is not a good way to start a "back to stay" project.
> --
However, there's nothing about the *CEV* design that precludes a
significantly different misssion profile: dry launch, use of an orbital
propellant depot filled by the cheapest available launcher, and
possibly reusable lunar landers.
Will McLean
Jonathan Goff
> However, there's nothing about the *CEV* design that precludes a
> significantly different misssion profile: dry launch, use of an orbital
> propellant depot filled by the cheapest available launcher, and
> possibly reusable lunar landers.
Well, that's only technically true. Sure, you could eventually evolve
it
into something useful, but at that point there would be nothing of the
original CEV architecture left. It would basically be entirely new
vehicles.
The LSAM for instance, can't really be modified into being reusable.
You can design an entirely new reusable lander, but then that begs the
question of why not design it to be reusable from the start? You could
make a dry-launched EDS vehicle, but what vehicle could realistically
dry launch something that bulky? And the thing really has none of the
equipment that would be necessary to allow it be reused.
A truly cost effective and useful lunar architecture is doable, but why
waste billions of taxpayer dollars on building what is really a useless
technological dead-end when you already admit that there are likely
better ways of doing it (ways that might even be cheaper to field) ?
~Jonathan Goff
www.selenianboondocks.com
genedi...@hotmail.com
between Soyuz and GE's original Apollo proposal. I can't remember if
the article suggested good old Soviet reverse engineering.
Gene DiGennaro
Baltimore, Md.
Will McLean
Jonathan Goff wrote:
> Will McLean wrote:
>
> > However, there's nothing about the *CEV* design that precludes a
> > significantly different misssion profile: dry launch, use of an orbital
> > propellant depot filled by the cheapest available launcher, and
> > possibly reusable lunar landers.
>
> Well, that's only technically true. Sure, you could eventually evolve
> it
> into something useful, but at that point there would be nothing of the
> original CEV architecture left. It would basically be entirely new
> vehicles.
The CEV, however, could be used essentially as is in the mission
profile I described.
> The LSAM for instance, can't really be modified into being reusable.
> You can design an entirely new reusable lander, but then that begs the
> question of why not design it to be reusable from the start?
Look again. Delete the ascent tanks and engine and you have a vehicle
that can get to the surface and back if it starts from lunar orbit with
full tanks.
> You could
> make a dry-launched EDS vehicle, but what vehicle could realistically
> dry launch something that bulky? And the thing really has none of the
> equipment that would be necessary to allow it be reused.
>
> A truly cost effective and useful lunar architecture is doable, but why
> waste billions of taxpayer dollars on building what is really a useless
> technological dead-end when you already admit that there are likely
> better ways of doing it (ways that might even be cheaper to field) ?
>
> ~Jonathan Goff
> www.selenianboondocks.com
Note that nobody is going to spend serious money on EDS, LSAM or CaLV
until after 2010. So there is plenty of time for a different plan if
some of the uncertainties of the "likely better ways " get resolved.
Will McLean
Jonathan Goff
> The CEV, however, could be used essentially as is in the mission
> profile I described.
Wow. Gosh, isn't that great. We have a CEV that can only be
launched on a government booster, and we have an EDS and
LSAM that need to be completely redesigned, but at least we
can reuse the CEV design itself! It could've been designed to
be launchable on current and future commercial vehicles, but that
wouldn't provide ATK and P&W enough pork, now would it?
> Look again. Delete the ascent tanks and engine and you have a vehicle
> that can get to the surface and back if it starts from lunar orbit with
> full tanks.
With only a tiny amount of cargo compared to the vehicle size.
Maybe if you also had tons of propellant on the lunar surface,
maybe the LSAM as designed could just drop the ascent tanks
and engine (and redesign the structure, and the electronics, but
hey, what's a bunch of costly redesigns between friends?) and
still be useful...but I doubt it. If they actually wanted a design
that could transition to reusability over time, they could have
picked that. But they picked Apollo on Steroids instead.
> Note that nobody is going to spend serious money on EDS, LSAM or CaLV
> until after 2010. So there is plenty of time for a different plan if
> some of the uncertainties of the "likely better ways " get resolved.
Yeah right. Do you honestly think all those "political realities"
are going to magically change themselves just because a better
technical solution comes along? NASA is doing a little to help
put those technologies on the shelf, but when you look at the
relative amounts of funding, the misprioritization is huge. When
you have big technical unknowns that have potentially large
payoffs, you find ways to retire them early. Things like prizes
or fixed-price contracts for demonstrating the technologies in
question. Instead, they're trying to funnel more and more money
into dead ends like the Shaft.
NASA could still do the right thing here, and there are good
people there trying to keep our options open, but the general
direction that Griffin is taking with most of this is discouraging.
~Jon
Brian Thorn
wrote:
>Will McLean wrote:
>
>> However, there's nothing about the *CEV* design that precludes a
>> significantly different misssion profile: dry launch, use of an orbital
>> propellant depot filled by the cheapest available launcher, and
>> possibly reusable lunar landers.
>
>Well, that's only technically true. Sure, you could eventually evolve
>it
>into something useful, but at that point there would be nothing of the
>original CEV architecture left.
I really wasn't referring to the entire Constellation architecture,
but the CEV design (the Apollo-like spacecraft) itself. Aside from
being too heavy, I don't understand why so much hostility to it.
Brian
Brian Thorn
wrote:
>While he may not be expressing it well, there's a real problem there.
>Apollo's design wasn't a bad one, given its limited political objectives
>(which did include haste and didn't include graceful expansion for more
>ambitious missions). The mistake is to repeat it, when its job was done
>thirty years ago and doesn't need re-doing.
The Super SDLV launch concept, yes, I agree, is unsustainable
long-term. But I was referring specifically to the CEV design (the
Apollo-like ship) since that is what Mr. Wade evidently had a severe
allergic reaction to.
>The CEV design is, as has often been said, "Apollo on steroids"... and
>that's *all* it is.
What else do we need it to be? We don't need a spaceborne lab, we
already have (to one extent or another) ISS. We don't need a space
truck... we've already ground-ruled out cargo and crew on the same
flight. What we need is something that can take crew to and from ISS
five years from now, and can be upgraded to take crew to and from
lunar orbit maybe ten years from now. CEV, if the goal of flying each
one ten times (is that where the extra mass is going?) seems
completely satisfactory for the job.
> Its basic mission profile -- LOR with an expendable
>spacecraft -- is optimized for occasional short visits on a generous
>budget.
Yes, but this is different from Soyuz, how? Soyuz is and CEV is
planned to be rated for 6 mos. orbital life. Six months at ISS or on
the moon is not exactly a short visit.
>This is not a good way to start a "back to stay" project.
It seems to me that the CEV is the part that will have the least
effect on how sustainable the project is. The design and concept of
the LSAM and EDS, I think will be much more influential. We can get
along without an SDLV, if startups can make the propellant depot
concept affordable, and the LSAM design should become easily reusable
if we find propellant manufacturing on the moon is possible (delete
the ascent engine and staging systems, replace with more propellant
tankage). But we're still going to need something for the crew to ride
into orbit and back aboard.
Brian
Rand Simberg
>On 6 Feb 2006 10:30:20 -0800, "Jonathan Goff" <jon...@gmail.com>
Because it continues to assume that the cost of spacelift will be
high.
Henry Spencer
Will McLean <mclea...@aol.com> wrote:
>However, there's nothing about the *CEV* design that precludes a
>significantly different misssion profile: dry launch, use of an orbital
>propellant depot filled by the cheapest available launcher, and
>possibly reusable lunar landers.
There's nothing about it that particularly facilitates them, either. For
example, if you're going to switch to a reusable lander before very long,
then the money spent developing the expendable one is basically wasted.
A system designed from the start for sustained long-term operations would
look quite different.
Tom Cuddihy
NASA's current CEV designs are all about rational and traceable program
management. If NASA had selected a CEV on merits, for instance, that
required L1 RDV or refeuling on orbit, that would in actuality be
letting the tail wag the dog --when NASA has to fund the whole
architecture and mission, not just a particular CEV design.
Steidle's CEV competition and spirals, if carried out the way they were
intended, would have been in effect the administration outsourcing the
vast majority of decision making and, realistically, most of the NASA
budget, to whatever random single source contractor was selected to
lead the effort. a FIAsco in the making. Griffen recognized that as
soon as he came aboard.
What's the matter with outsourcing decision making of that scope? Just
ask the NRO about FIA E-O. A responsible single-source customer, which
NASA was NOT going to be under Steidle, needs to be able to understand
the real costs and benefits of each design trade, and to have an
institutional understanding of why things work the way they do. The
customer needs to understand the actual scope of the contract before
signing away NASA's decision making ability to a particular design.
Otherwise, the smallest details can take on a life of their own and end
up driving your program away from its targets, off the tracks, and into
the ditch of congressional cancellation. Yes, NASA's current CEV design
seems overly conservative, a little over-sized, and operationally
stone-aged. Or at least Apollo-aged. But the costs and benefits that
drove the design are well understood by the program managers at NASA,
the boundaries will be clear, and it will be easy to recognize the
scope of the program as it ramps up.
There will not be nasty suprises about the difficulty of orbital
refueling, integrating 8 pieces for a single lunar mission, developing
rendezvoud methods with a CEV that has no windows, or funding an
entirely new ISS at L1. The scope of the problem is understood and
tested. Perhaps most importantly, there will be no fantasies (or fears)
about a government design turning into a sustainable architecture. That
will at least keep any potential investors in NewSpace from thinking
that NASA is going to fund an AMTRAK to orbit.
Jim Kingdon
> but the CEV design (the Apollo-like spacecraft) itself. Aside from
> being too heavy, I don't understand why so much hostility to it.
"Aside from being too heavy"....
Well, that's a pretty big one right there. Masses significantly more
than Apollo, doesn't do more than Apollo.
Will McLean
33% more crew (twice as much for space station ferry), lands on land,
reusable, vastly increased orbital storage.
And less..uh...spartan..hygiene arrangements.
Will McLean
Will McLean
Jonathan Goff wrote:
> Will,
>
> > The CEV, however, could be used essentially as is in the mission
> > profile I described.
>
> Wow. Gosh, isn't that great. We have a CEV that can only be
> launched on a government booster, and we have an EDS and
> LSAM that need to be completely redesigned, but at least we
> can reuse the CEV design itself! It could've been designed to
> be launchable on current and future commercial vehicles, but that
> wouldn't provide ATK and P&W enough pork, now would it?
>
The current design is launchable on the larger EELVs and Falcon 9 (if
it meets its payload goals). Doing the lunar mission with acceptable
abort options would require orbital refueling or an upgraded upper
stage for the EELVs.
Major drivers for putting it on the CLV are a perception that the
government is enormously squeamish about astronaut casualties, and the
desire to preserve production capacity for SRBs.
> > Look again. Delete the ascent tanks and engine and you have a vehicle
> > that can get to the surface and back if it starts from lunar orbit with
> > full tanks.
>
> With only a tiny amount of cargo compared to the vehicle size.
> Maybe if you also had tons of propellant on the lunar surface,
> maybe the LSAM as designed could just drop the ascent tanks
> and engine (and redesign the structure, and the electronics, but
> hey, what's a bunch of costly redesigns between friends?) and
> still be useful...but I doubt it. If they actually wanted a design
> that could transition to reusability over time, they could have
> picked that. But they picked Apollo on Steroids instead.
>
> > Note that nobody is going to spend serious money on EDS, LSAM or CaLV
> > until after 2010. So there is plenty of time for a different plan if
> > some of the uncertainties of the "likely better ways " get resolved.
>
> Yeah right. Do you honestly think all those "political realities"
> are going to magically change themselves just because a better
> technical solution comes along?
Quite possibly. One of the political realities is an arbitrary
deadline. The next administration may feel differently. Or the next
after that.
> NASA is doing a little to help
> put those technologies on the shelf, but when you look at the
> relative amounts of funding, the misprioritization is huge. When
> you have big technical unknowns that have potentially large
> payoffs, you find ways to retire them early.
OK. Take unmanned orbital rendezvous and docking. All you have to do is
fund a spacecraft to demonstrate that you can do that with great
reliability. (Crunch) Well, try again.
If you design on the assumption that unmanned orbital rendezvous and
docking (or berthing) and orbital cryogenic fuel transfer will be
dependable and routine, and that cheap commercial launch will be
available when you need it, and you design to take full advantage of
those assumptions and you are right, great. If you are wrong, now you
have to redesign everything to work the other way.
Even with a lot more funding, you won't know if you are right for
years.
>Things like prizes
> or fixed-price contracts for demonstrating the technologies in
> question.
Helpful, but not a panacea. Note that Kistler has a partially completed
vehicle, and NASA has given a contract that pays them if they
demonstrate it will work. It's still in the hanger.
Will McLean
Michael Gallagher
wrote:
>Wade carries on about how NASA is "making the same mistake as Apollo"
>(almost as if Apollo lost the moon race) but nowhere in his anti-US
>tirade does he explain why NASA's CEV design is bad ....
Not only that, but his comment that Soyuz is still in use after 40
years while Apollo didn't last implies the Soyuz design is superior,
and ignores the politcal realiies on both sides of the iron curtain:
The US' decision to go with the Shuttle and the Soviets decision to
continue using Soyuz technoloyg probably had to do more with what
their respective governments would pay for than which one was better
or worse.
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Will McLean
Brian Thorn wrote:
> On Sun, 05 Feb 2006 07:45:49 -0600, Pat Flannery <fla...@daktel.com>
> wrote:
>
> >Mark Wade has added information to his Encyclopedia Astronautica website
> >about the history and contenders for the CEV design:
> >http://www.astronautix.com/craftfam/cev.htm
> >The final Lockheed design looked like a Soyuz A:
> >http://www.astronautix.com/graphics/z/zcevlocm.jpg
> >http://www.astronautix.com/craft/soyuza.htm
>
> Another EA opportunity to dump on the US, I see. Has Wade ever made a
> positive comment about NASA?
>
> Why he's fixating on the "superiority" of Soyuz's three-module
> arrangement (again) is baffling.
He's made the careless mistake of comparing the Earth-orbit Soyuz and
the lunar orbit CM. If you ignore the different roles, the Soyuz looks
lighter and roomier.
But the Lunar orbit version of the Soyuz was a two-seater, and the crew
compartments weighed more per seat than the CM and had additional
failure modes.
Note that on Boeing's Soyuz-style design, the orbital and entry modules
are more massive and complicated than the unitary design actually
selected.
Will
Henry Spencer
Will McLean <mclea...@aol.com> wrote:
>> ...Sure, you could eventually evolve it
>> into something useful, but at that point there would be nothing of the
>
>The CEV, however, could be used essentially as is in the mission
>profile I described.
Yes, but your mission profile is still very much like the existing one.
It's not clear that we are well-served by anything like that profile. For
example, if not just the lander but also the Earth-Moon transport becomes
reusable -- perhaps with a high-performance lander based in LEO, perhaps
with an inter-orbit transport based in LEO and a lander based in lunar
orbit -- then there is no role left for an Apollo-style capsule at all.
Even if you stick with an expendable lander, as payload to the surface
increases and stay times get longer, leaving part of the hardware in orbit
imposes more and more penalties. Eventually you start wanting to build a
lightweight return vehicle -- the lighter, the better -- which is taken
down to the surface. Here you still have an Apollo-style capsule with a
propulsion module under it, but it almost certainly can't be the big heavy
one being designed for CEV.
Rand Simberg
he...@spsystems.net (Henry Spencer) made the phosphor on my monitor
glow in such a way as to indicate that:
>In article <1139254275.1...@z14g2000cwz.googlegroups.com>,
Yes, the current architecture (and CEV design) assumes that people
returning from the moon will always return all the way to earth. Get
rid of this requirement (for instance, by developing routine
transportation to/from LEO) and now someone on a lunar excursion would
return instead to LEO, and there would be no need for a capsule with
big heat shield.
Jeff Findley
"Rand Simberg" <simberg.i...@org.trash> wrote in message
news:44242423....@news.giganews.com...
>
> Yes, the current architecture (and CEV design) assumes that people
> returning from the moon will always return all the way to earth. Get
> rid of this requirement (for instance, by developing routine
> transportation to/from LEO) and now someone on a lunar excursion would
> return instead to LEO, and there would be no need for a capsule with
> big heat shield.
Aerobraking and/or propulsive entry into LEO from the trans-lunar
trajectory?
Jeff
--
Remove icky phrase from email address to get a valid address.
Will McLean
Henry Spencer wrote:
> In article <1139254275.1...@z14g2000cwz.googlegroups.com>,
> Will McLean <mclea...@aol.com> wrote:
> >> ...Sure, you could eventually evolve it
> >> into something useful, but at that point there would be nothing of the
> >> original CEV architecture left...
> >
> >The CEV, however, could be used essentially as is in the mission
> >profile I described.
>
> Yes, but your mission profile is still very much like the existing one.
> It's not clear that we are well-served by anything like that profile. For
> example, if not just the lander but also the Earth-Moon transport becomes
> reusable -- perhaps with a high-performance lander based in LEO, perhaps
> with an inter-orbit transport based in LEO and a lander based in lunar
> orbit -- then there is no role left for an Apollo-style capsule at all.
>
That's a lot of perhaps. (And assumes something other than the capsule
to get from Earth to to LEO)
And not all of these scenarios dispense with the capsule. It might be
most economical to recover your EDS stage by multi-pass aerocapture,
but you wouldn't want to subject your crew to that.
> Even if you stick with an expendable lander, as payload to the surface
> increases and stay times get longer, leaving part of the hardware in orbit
> imposes more and more penalties.
Can you be more specific? If you are building a robust surface base,
the need for anytime return decreases: if someone has apendicitis, you
treat him in sick bay rather than sending him on a week long space
voyage home. And space seems like a more benign place than the lunar
surface, being beaten up by the long day-night cycle.
> Eventually you start wanting to build a
> lightweight return vehicle -- the lighter, the better -- which is taken
> down to the surface. Here you still have an Apollo-style capsule with a
> propulsion module under it, but it almost certainly can't be the big heavy
> one being designed for CEV.
> --
> spsystems.net is temporarily off the air; | Henry Spencer
> mail to henry at zoo.utoronto.ca instead. | he...@spsystems.net
And what superfluous mass do you remove? If you can pare the mass
safely, why haven't you already done so?
(And now you start wanting an airlock on or in the capsule so you don't
track in as much dust. Which conflicts with the desire to make it as
light as possible.)
Will McLean
Rand Simberg
Findley" <jeff.f...@ugs.nojunk.com> made the phosphor on my monitor
glow in such a way as to indicate that:
>
>"Rand Simberg" <simberg.i...@org.trash> wrote in message
>news:44242423....@news.giganews.com...
>>
>> Yes, the current architecture (and CEV design) assumes that people
>> returning from the moon will always return all the way to earth. Get
>> rid of this requirement (for instance, by developing routine
>> transportation to/from LEO) and now someone on a lunar excursion would
>> return instead to LEO, and there would be no need for a capsule with
>> big heat shield.
>
>Aerobraking and/or propulsive entry into LEO from the trans-lunar
>trajectory?
Either or both, depending on the cost of propellant on the moon or at
EML1.
Brian Thorn
It's baseline crew of six versus Apollo's baseline three (Apollo was
capable of five, but only at significantly higher risk to the crew.)
It's baseline ground landing versus baseline water splashdown (Apollo
could do ground landing as well, but again, only at significantly
higher risk to the crew.) CEV's design goal is six months flight. We
don't know what Apollo could have been pushed to, but SL-3 showed it
ran into problems on long flights. CEV is intended for at least some
reusability, and this, I suspect, is where most of the extra mass is
going.
Brian
Brian Thorn
Simberg) wrote:
>Yes, the current architecture (and CEV design) assumes that people
>returning from the moon will always return all the way to earth.
A fairly safe assumption.
>Get
>rid of this requirement (for instance, by developing routine
>transportation to/from LEO) and now someone on a lunar excursion would
>return instead to LEO, and there would be no need for a capsule with
>big heat shield.
Then how do you get back into LEO? Aerobraking is still going to need
a big heat shield and/or heavy hulls for radiation protection.
Propulsive LEO entry is going to need much more mass than a big heat
shield, plus a bigger engine for TEI and LEOI, plus a bigger booster
for TLI.
Straight in seems far more economical, especially if the crew module
is reusable, as CEV is meant to be (with a new, bolt-on heat shield.)
Brian
Pat Flannery
Will McLean wrote:
>The current design is launchable on the larger EELVs and Falcon 9 (if
>it meets its payload goals).
>
>
>
Let's see Falcon 1 get airborne before we even begin discussing what a
Falcon 9 can do.
Pat
Rand Simberg
Thorn <btho...@cox.net> made the phosphor on my monitor glow in such
a way as to indicate that:
>On Tue, 07 Feb 2006 22:52:03 GMT, simberg.i...@org.trash (Rand
>Simberg) wrote:
>
>
>>Yes, the current architecture (and CEV design) assumes that people
>>returning from the moon will always return all the way to earth.
>
>A fairly safe assumption.
Not for long, if private enterprise starts to get serious about LEO.
>>Get
>>rid of this requirement (for instance, by developing routine
>>transportation to/from LEO) and now someone on a lunar excursion would
>>return instead to LEO, and there would be no need for a capsule with
>>big heat shield.
>
>Then how do you get back into LEO? Aerobraking is still going to need
>a big heat shield and/or heavy hulls for radiation protection.
Not as big as an entry heatshield. And it doesn't need the L/D. It's
a different design.
>Propulsive LEO entry is going to need much more mass than a big heat
>shield, plus a bigger engine for TEI and LEOI, plus a bigger booster
>for TLI.
Mass isn't the issue--cost is. And that depends on the cost of
propellants in various locations.
>Straight in seems far more economical, especially if the crew module
>is reusable, as CEV is meant to be (with a new, bolt-on heat shield.)
Under current infrastructure (and high cost of access) assumption,
yes. We need to change that, but instead, NASA is simply accepting
it, and building yet another unaffordable, unsustainable program.
Jorge R. Frank
news:442858de....@news.giganews.com:
> On Tue, 07 Feb 2006 17:34:46 -0600, in a place far, far away, Brian
> Thorn <btho...@cox.net> made the phosphor on my monitor glow in such
> a way as to indicate that:
>
>>On Tue, 07 Feb 2006 22:52:03 GMT, simberg.i...@org.trash (Rand
>>Simberg) wrote:
>>
>>>Get
>>>rid of this requirement (for instance, by developing routine
>>>transportation to/from LEO) and now someone on a lunar excursion would
>>>return instead to LEO, and there would be no need for a capsule with
>>>big heat shield.
>>
>>Then how do you get back into LEO? Aerobraking is still going to need
>>a big heat shield and/or heavy hulls for radiation protection.
>
> Not as big as an entry heatshield. And it doesn't need the L/D. It's
> a different design.
Scary. Aerocapture is sensitive to atmospheric conditions, and slight
errors in navigation or targeting could be fatal if you don't have an
"abort-to-surface" option. And the easiest way to do that is to size your
aerocapture heatshield for entry.
--
JRF
Reply-to address spam-proofed - to reply by E-mail,
check "Organization" (I am not assimilated) and
think one step ahead of IBM.
Rand Simberg
R. Frank" <jrf...@ibm-pc.borg> made the phosphor on my monitor glow
in such a way as to indicate that:
>>>Then how do you get back into LEO? Aerobraking is still going to need
>>>a big heat shield and/or heavy hulls for radiation protection.
>>
>> Not as big as an entry heatshield. And it doesn't need the L/D. It's
>> a different design.
>
>Scary. Aerocapture is sensitive to atmospheric conditions, and slight
>errors in navigation or targeting could be fatal if you don't have an
>"abort-to-surface" option. And the easiest way to do that is to size your
>aerocapture heatshield for entry.
Perhaps, but I'd prefer propulsion anyway. It's all a matter of
building an orbital propellant infrastructure, which to me is an
intrinsic part of being spacefaring, and which is also sadly something
that Mike Griffin's NASA seems quite resistant to doing.
Brian Thorn
Simberg) wrote:
>Perhaps, but I'd prefer propulsion anyway. It's all a matter of
>building an orbital propellant infrastructure, which to me is an
>intrinsic part of being spacefaring, and which is also sadly something
>that Mike Griffin's NASA seems quite resistant to doing.
For good reason. You try explaining this one to Congress...
"First, we need a launcher and a ship to get materials to L1 (or
wherever) to build a Prop Depot. That ship has to be self-sufficient
at first, because there is no Prop Depot yet for them to top off the
tanks and burn back into LEO on the way home. Um, yes Senator,
technically that means we'll have a ship that can go to the Moon
without needing a Prop Depot, but really... hear me out... Then, once
we have a Prop Depot, we'll need a new, much cheaper ship that just
goes back and forth from LEO to the Prop Depot. And if something goes
wrong and it can't get to the Depot, the crew's dead, because it can't
re-enter Earth's atmosphere on its own, we cut that heat shield to
save weight, and it won't have enough fuel to burn back into LEO, but
don't worry...
And oh, by the way, the companies we want to launch our ship and build
our Prop Depot, you've probably never heard of them, and the only one
who's actually built a real spacecraft only got it to Mach 3 and 62
miles up, but that's the only way we can afford this. Can we have our
$5B check now, please?"
Is it any wonder NASA hasn't gone to Congress with something like
this? :-)
So that's how we got Constellation (although I'd prefer EELV-derived
launch systems, that's really just a small detail in the big picture).
About the best we can hope for is that the Constellation architecture
is sufficiently flexible to adapt to new infrastructure as it comes
along, i..e, replace the EDS with tank farm refuelling, but keep the
CEV and LSAM. Or replace the CEV with a t/Space vehicle or two
launched by Falcon 9s as they become available, but keep the EDS and
the LSAM. Or never build the current LSAM at all (we have years to
decide on this still) and instead build a reusable lander system
that's refuelled at an L1 Prop Depot...
Brian
Rand Simberg
Thorn <btho...@cox.net> made the phosphor on my monitor glow in such
a way as to indicate that:
>>Perhaps, but I'd prefer propulsion anyway. It's all a matter of
>>building an orbital propellant infrastructure, which to me is an
>>intrinsic part of being spacefaring, and which is also sadly something
>>that Mike Griffin's NASA seems quite resistant to doing.
>
>For good reason. You try explaining this one to Congress...
>
>"First, we need a launcher and a ship to get materials to L1 (or
>wherever) to build a Prop Depot. That ship has to be self-sufficient
>at first, because there is no Prop Depot yet for them to top off the
>tanks and burn back into LEO on the way home. Um, yes Senator,
>technically that means we'll have a ship that can go to the Moon
>without needing a Prop Depot, but really... hear me out... Then, once
>we have a Prop Depot, we'll need a new, much cheaper ship that just
>goes back and forth from LEO to the Prop Depot. And if something goes
>wrong and it can't get to the Depot, the crew's dead, because it can't
>re-enter Earth's atmosphere on its own, we cut that heat shield to
>save weight, and it won't have enough fuel to burn back into LEO, but
>don't worry...
>And oh, by the way, the companies we want to launch our ship and build
>our Prop Depot, you've probably never heard of them, and the only one
>who's actually built a real spacecraft only got it to Mach 3 and 62
>miles up, but that's the only way we can afford this. Can we have our
>$5B check now, please?"
>
>Is it any wonder NASA hasn't gone to Congress with something like
>this? :-)
Yes, I'm sure that that's exactly the way they'd "sell" it.
That is, if they wanted to do what they're doing now...
There is, of course, a better way to sell it to Congress (and more
importantly, at least one hopes, to the American people).
It would be a useful exercise to rewrite your cynical nonsense to
demonstrate that, but unfortunately, I'm too busy right now trying to
help one of the bidders win the business for this monstrosity. But
remind me again in a couple weeks--it would make a good blog post.
>So that's how we got Constellation (although I'd prefer EELV-derived
>launch systems, that's really just a small detail in the big picture).
>About the best we can hope for is that the Constellation architecture
>is sufficiently flexible to adapt to new infrastructure as it comes
>along, i..e, replace the EDS with tank farm refuelling, but keep the
>CEV and LSAM. Or replace the CEV with a t/Space vehicle or two
>launched by Falcon 9s as they become available, but keep the EDS and
>the LSAM. Or never build the current LSAM at all (we have years to
>decide on this still) and instead build a reusable lander system
>that's refuelled at an L1 Prop Depot...
It that's the best we can hope for, then it's pretty hopeless.
Thankfully, NASA's plans are almost completely irrelevant to our
nation's (or our species') future in space.
richard schumacher
he...@spsystems.net (Henry Spencer) wrote:
> Yes, but your mission profile is still very much like the existing one.
> It's not clear that we are well-served by anything like that profile. For
> example, if not just the lander but also the Earth-Moon transport becomes
> reusable -- perhaps with a high-performance lander based in LEO, perhaps
> with an inter-orbit transport based in LEO and a lander based in lunar
> orbit -- then there is no role left for an Apollo-style capsule at all.
>
> Even if you stick with an expendable lander, as payload to the surface
> increases and stay times get longer, leaving part of the hardware in orbit
> imposes more and more penalties. Eventually you start wanting to build a
> lightweight return vehicle -- the lighter, the better -- which is taken
> down to the surface. Here you still have an Apollo-style capsule with a
> propulsion module under it, but it almost certainly can't be the big heavy
> one being designed for CEV.
Does anyone point these things out to Barbara Mikulski or Dana
Rohrbacker?
Will McLean
I see that Mike Griffin's NASA is proposing a Fuel Depot Demonstration
Challenge with a $5 million purse. The draft rules are out for comment,
you might wish to write in.
Elsewhere, Griffin has said that if a commercial provider can get
propellant to an orbital fuel depot cheaper than NASA can launch it on
the SDHLV, he would very much like to use it to refuel the departure
stage so it can loft more payload to the moon. Even at only two
launches a year, that's a substantial market by current launch
standards.
What Griffin does seem to be resistant to is betting the program on
orbital cryogenic propellant transfer and cheap launch being available
and dependable when needed. I'm not sure I blame him.
Will McLean
genedi...@hotmail.com
she doesn't give a fig about what is the most effiicient way to explore
the cosmos. Mikulski simply looks at NASA as an aerospace WPA project,
securing jobs for her home district. This is why she really wants a
Hubble repair mission. It's not that she is awed by the pretty
pictures, it's that the Space Telescope Science Institute is based at
Johns Hopkins in Baltimore. Every time she can win more work for the
defense contractors or Hopkins APL around here, the more she can count
on being re-elected. My guess is Rohrbacker is the same.
Gene
Rand Simberg
<mclea...@aol.com> made the phosphor on my monitor glow in such a
way as to indicate that:
>> Perhaps, but I'd prefer propulsion anyway. It's all a matter of
>> building an orbital propellant infrastructure, which to me is an
>> intrinsic part of being spacefaring, and which is also sadly something
>> that Mike Griffin's NASA seems quite resistant to doing.
>
>
>I see that Mike Griffin's NASA is proposing a Fuel Depot Demonstration
>Challenge with a $5 million purse. The draft rules are out for comment,
>you might wish to write in.
Yes, that is minimally encouraging.
>Elsewhere, Griffin has said that if a commercial provider can get
>propellant to an orbital fuel depot cheaper than NASA can launch it on
>the SDHLV, he would very much like to use it to refuel the departure
>stage so it can loft more payload to the moon. Even at only two
>launches a year, that's a substantial market by current launch
>standards.
Yes, but actions speak louder than words. Given NASA's history, it
would be a foolish investor indeed who took his word for it, when all
of his plans indicate otherwise.
>What Griffin does seem to be resistant to is betting the program on
>orbital cryogenic propellant transfer and cheap launch being available
>and dependable when needed. I'm not sure I blame him.
Instead he's betting the program on the odds that NASA and its
contractors will be able to manage a very expensive program over
multiple administrations with little to show for it for over a decade,
without Congress killing it.
I think that it would be a far safer bet to expect the market to step
up, if a credible incentive were offered.
snidely
genedi...@hotmail.com wrote:
> [...] My guess is Rohrbacker is the same.
I think he favors defense contractors. He is interested, for instance,
in a continuation of the C-17 program, "and not just because it is the
last plane being built on a California assembly line" (paraphrase of
remarks he made to KFWB on February 7).
I think he favors space projects to the extent that they help the same
consituency, but he does like the GeeWhizz aspect, too.
/dps
Will McLean
Rand Simberg wrote:
> On 8 Feb 2006 07:31:22 -0800, in a place far, far away, "Will McLean"
> <mclea...@aol.com> made the phosphor on my monitor glow in such a
> way as to indicate that:
>
> >> Perhaps, but I'd prefer propulsion anyway. It's all a matter of
> >> building an orbital propellant infrastructure, which to me is an
> >> intrinsic part of being spacefaring, and which is also sadly something
> >> that Mike Griffin's NASA seems quite resistant to doing.
> >
> >
> >I see that Mike Griffin's NASA is proposing a Fuel Depot Demonstration
> >Challenge with a $5 million purse. The draft rules are out for comment,
> >you might wish to write in.
>
> Yes, that is minimally encouraging.
>
> >Elsewhere, Griffin has said that if a commercial provider can get
> >propellant to an orbital fuel depot cheaper than NASA can launch it on
> >the SDHLV, he would very much like to use it to refuel the departure
> >stage so it can loft more payload to the moon. Even at only two
> >launches a year, that's a substantial market by current launch
> >standards.
>
> Yes, but actions speak louder than words. Given NASA's history, it
> would be a foolish investor indeed who took his word for it, when all
> of his plans indicate otherwise.
>
I would certainly want to keep NASA's institutional imperatives in
mind. For it to be attractive to NASA, the depot has to be able to
deliver 125 tons of propellant for less than the marginal cost of
launching the CaLV and an unmanned lander. If it can do that, however,
I don't see a major reason for NASA not to buy it.
By using the EDS to brake into lunar orbit rather than the lander, the
lander should be able to land an extra seven tons of payload on the
surface without major changes to the design. Stretch the lander, and
you can get more, at the cost of more fuel from the depot.
All things being equal, NASA shouldn't have much preference between
buying the extra hardware and buying the propellant: the NASA fiefdoms
will stay much the same size in either case. But if the depot costs
less, paying less for the transport will be a plus for NASA, since
money will be tight.
Will McLean
Rand Simberg
Because it makes the prodigious investment in the (unnecessary) heavy
lifter, with its expensive ground infrastructure, look foolish?
Will McLean
What looks foolish is coming up with some bogus reason why you can't
use cheap fuel from an orbital fuel depot after you've said how much
you wanted to.
In any case, there are plenty of plausible sounding reasons the NASA
head at the time can advance for why a heavy lift vehicle is still
desirable: launching the Mars Reference Mission, avoiding orbital
assembly, and providing a much less constrained shroud.
If it's someone other than Griffin he can add that it's a different
NASA now and it's time to look forward, not back, etc etc.
They aren't going to spend serious money on the CaLV before 2009 at the
earliest. If orbital propellant transfer starts looking better by then,
the cost of changing plans will be minimal.
Will McLean
Rand Simberg
>They aren't going to spend serious money on the CaLV before 2009 at the
>earliest. If orbital propellant transfer starts looking better by then,
>the cost of changing plans will be minimal.
Perhaps, but that begs the question of whether or not they're going to
do much to make it look better by then, and whether benign neglect
will result in it.
I'm glad that they have a Centennial Challenges prize for a depot
demonstration, but it seems ridiculously underfunded to me. Given
current launch costs, how in the world do they think that anyone would
be able to do it within an order of magnitude of five million? And if
it turns out that someone can, it throws all of NASA's plans in a
cocked hat, in terms of the implications for launch costs and orbital
operations.
Will McLean
Rand Simberg wrote:
> On 9 Feb 2006 06:45:17 -0800, in a place far, far away, "Will McLean"
> <mclea...@aol.com> made the phosphor on my monitor glow in such a
> way as to indicate that:
>
> >They aren't going to spend serious money on the CaLV before 2009 at the
> >earliest. If orbital propellant transfer starts looking better by then,
> >the cost of changing plans will be minimal.
>
> Perhaps, but that begs the question of whether or not they're going to
> do much to make it look better by then, and whether benign neglect
> will result in it.
>
Orbital Expressed is scheduled to do multiple automated dockings and
fuel transfers before then. (Admittedly, non cryogenic). And if Musk
can actually deliver the Falcon 9 for the price he claims, the depot
looks a lot more attractive.
> I'm glad that they have a Centennial Challenges prize for a depot
> demonstration, but it seems ridiculously underfunded to me. Given
> current launch costs, how in the world do they think that anyone would
> be able to do it within an order of magnitude of five million?
Secondary payload attached to a LOX using upper stage, using the
residual propellant. Note that the amount you need to store is fairly
small.
For extra savings, have the team be a part of a rocket company that's
only paying marginal cost.
Will McLean
Rand Simberg
>> >They aren't going to spend serious money on the CaLV before 2009 at the
>> >earliest. If orbital propellant transfer starts looking better by then,
>> >the cost of changing plans will be minimal.
>>
>> Perhaps, but that begs the question of whether or not they're going to
>> do much to make it look better by then, and whether benign neglect
>> will result in it.
>
>Orbital Expressed is scheduled to do multiple automated dockings and
>fuel transfers before then. (Admittedly, non cryogenic). And if Musk
>can actually deliver the Falcon 9 for the price he claims, the depot
>looks a lot more attractive.
For sure.
>> I'm glad that they have a Centennial Challenges prize for a depot
>> demonstration, but it seems ridiculously underfunded to me. Given
>> current launch costs, how in the world do they think that anyone would
>> be able to do it within an order of magnitude of five million?
>
>Secondary payload attached to a LOX using upper stage, using the
>residual propellant. Note that the amount you need to store is fairly
>small.
I haven't read the rules yet (too busy), but would that win the prize?
What technologies are they trying to demonstrate? Just LOX transfer?
Will McLean
Rand Simberg wrote:
>
> >> I'm glad that they have a Centennial Challenges prize for a depot
> >> demonstration, but it seems ridiculously underfunded to me. Given
> >> current launch costs, how in the world do they think that anyone would
> >> be able to do it within an order of magnitude of five million?
> >
> >Secondary payload attached to a LOX using upper stage, using the
> >residual propellant. Note that the amount you need to store is fairly
> >small.
>
> I haven't read the rules yet (too busy), but would that win the prize?
> What technologies are they trying to demonstrate? Just LOX transfer?
See below. They're not as clearly worded as they could be. As I read
them, you need to get the required amount of LOX and LH to orbit, store
them in tanks for a total of 120 days and at least two weeks before the
end of the period, get them into separate tanks and keep them liquid
until the end of the period
I hope the intent is to include propellant transfer, since that's the
important problem. But the wording is ambiguous.
The most elegant solution would use a LH fueled upper stage, and use
residual fuel for the LH demonstration as well. However, they aren't
always going to LEO, and the people that launch them may be less
cooperative about modifications to their stage. The 20 kg of LH
required could use dedicated tanks.
Will McLean
Appendix 1. The Fuel Depot Demonstration Challenge - Draft Rules
Overview
The purpose of the Fuel Depot Demonstration Challenge is to promote the
development of cryogenic fluid management technologies that have wide
application in the space community. The development of a
high-efficiency cryogenic fluid storage and transfer system could
significantly lower the cost and complexity of space exploration
missions and enable new commercial space markets.
The Fuel Depot Demonstration Challenge purse of $5,000,000 will be
awarded to the first team that could build, launch, and demonstrate a
subscale liquid hydrogen and liquid oxygen storage or production
facility system in Earth orbit.
Definitions
a. Advance Notification Information - In accordance with the Advance
Notification Period Terms, Team will:
(1) Provide to Org the location and the start date of the Competition
Attempt.
(2) Provide to Org a detailed description (and possible demonstration)
of their System's safe design and operation.
(3) Provide to Org a detailed description of, and receive written
acceptance of, the data acquisition methods employed to verify and
validate System performance in order to win the Challenge. If Org does
not approve the proposed data acquisition methods, Org will identify
specific shortcomings and provide this information to the Team. It will
then be the responsibility of Team to resubmit a new data acquisition
procedure that addresses the shortcomings of their previous submission.
(4) Notify Org of any known Competition Attempt delays at its earliest
opportunity. If, in the opinion of Org, Team provides serial notices of
delays for the purpose of gaining competitive advantage, the Team will
be required to reinitiate the advance notification process.
b. Advance Notification Period Terms - At least 60 days prior to any
Competition Attempt:
(1) Team must be officially registered and provide their intent to
compete in the Challenge by providing design compliance and operational
safety information to Org.
(2) Team will provide Org with all Advance Notification Information.
(3) Team will show or demonstrate compliance with all Minimum Design
Requirements.
c. Challenge - The Fuel Depot Demonstration Challenge.
d. Competition Attempt - The operation by Team of the System under Test
Conditions for the Test Duration with the intention of winning the
Challenge. The Competition Attempt will take place in accordance with
the Advance Notification Period Terms and consist of the following
events:
(1) Put a tank (or tanks) containing the Minimum Mass of the
Propellants in LEO. (NOTE: the Propellants can be delivered to LEO,
generated while in LEO, or anything else in between.)
(2) Store the Propellants in the tank (or tanks) for the Storage
Duration while in LEO.
(4) At least two weeks before the end of the Storage Duration in LEO,
the Propellant Minimum Mass should be liquefied and stored in separate
tanks as saturated liquids at 16 +/- 0.5 pounds per square inch
(absolute) for the remainder of the Storage Duration.
e. Deadline - January 1, 2012 (local date and time in Washington, D.C.,
U.S.A.). The Deadline may be extended at the sole discretion of NASA.
f. Low Earth Orbit - Any orbit around the Earth above the altitude of
200 kilometers, aka LEO.
g. Minimum Mass - At least 20 kg of liquid hydrogen and at least 120 kg
of liquid oxygen.
h. Minimum Design Requirements - The System shall:
(1) Be capable of storing the Minimum Mass of both Propellants in
separate tanks for the Storage Duration.
(2) Survive an Earth-to-orbit launch environment.
i. Org - Organization that is administering and executing the
Challenge.
j. Propellants - Hydrogen and oxygen.
k. Storage Duration - 120 days.
l. System - All equipment (including all hardware, software, power
system, thermal cooling system, etc.) that is part of the Propellant
production and storage system entered by Team to compete in the
Challenge.
Rules
a. Technical specifications not already covered in this Agreement about
any Challenge details will be provided by Org to Team at the time of
registration. These technical specifications may be subject to future
updates by Org at its sole discretion.
b. Before the Competition Attempt, Team shall comply with the Advance
Notification Period Terms.
c. For the Competition Attempt, Team shall provide or make arrangements
for the use of the System and all the other necessary launch vehicles,
test facilities, equipment, fluids, and consumables that will prove the
performance of their System.
d. The System must be launched into Low Earth Orbit and successfully
perform and complete all the Functional Tasks.
e. If Team successfully completes the Competition Attempt before the
Deadline, the Team shall be deemed the winner of the Challenge and
receive the prize purse of $5,000,000 (five million U.S. dollars).
Questions for Consideration by Respondent
Are any of the definitions given missing, over-specifying, or
incorrectly specifying important qualitative and quantitative
parameters? (E.g., the maximum allowable mass is too low, etc.) If so,
what should the proper parameter specification be and why?
Are there any logistical or practical situations that have been
overlooked? (E.g., considerations of safety, validation, operation of
the competition event, etc.) If so, what situation has been overlooked
and how should it be handled?
Is the prize purse adequately sized? Why or why not?
Are there alternative ideas for conducting the competition, or scoring
and awarding the prizes for the competition? If so, what are your
proposed ideas and why?
Rand Simberg
>
>Rand Simberg wrote:
>>
>> >> I'm glad that they have a Centennial Challenges prize for a depot
>> >> demonstration, but it seems ridiculously underfunded to me. Given
>> >> current launch costs, how in the world do they think that anyone would
>> >> be able to do it within an order of magnitude of five million?
>> >
>> >Secondary payload attached to a LOX using upper stage, using the
>> >residual propellant. Note that the amount you need to store is fairly
>> >small.
>>
>> I haven't read the rules yet (too busy), but would that win the prize?
>> What technologies are they trying to demonstrate? Just LOX transfer?
>
>
>See below. They're not as clearly worded as they could be. As I read
>them, you need to get the required amount of LOX and LH to orbit, store
>them in tanks for a total of 120 days and at least two weeks before the
>end of the period, get them into separate tanks and keep them liquid
>until the end of the period
If one has to do LH as well, then your solution proposed above
wouldn't work, per se.
>I hope the intent is to include propellant transfer, since that's the
>important problem. But the wording is ambiguous.
It's *an* important problem, but it's not *the* important problem.
There are a number of technologies to be developed (and which are
apparently being given short shrift by NASA), including transfer,
long-term storage, settling, ullage management, automated docking with
fueling, etc.
Will McLean
Rand Simberg wrote:
> On 9 Feb 2006 09:50:13 -0800, in a place far, far away, "Will McLean"
> <mclea...@aol.com> made the phosphor on my monitor glow in such a
> way as to indicate that:
>
> >
> >Rand Simberg wrote:
> >>
> >> >> I'm glad that they have a Centennial Challenges prize for a depot
> >> >> demonstration, but it seems ridiculously underfunded to me. Given
> >> >> current launch costs, how in the world do they think that anyone would
> >> >> be able to do it within an order of magnitude of five million?
> >> >
> >> >Secondary payload attached to a LOX using upper stage, using the
> >> >residual propellant. Note that the amount you need to store is fairly
> >> >small.
> >>
> >> I haven't read the rules yet (too busy), but would that win the prize?
> >> What technologies are they trying to demonstrate? Just LOX transfer?
> >
> >
> >See below. They're not as clearly worded as they could be. As I read
> >them, you need to get the required amount of LOX and LH to orbit, store
> >them in tanks for a total of 120 days and at least two weeks before the
> >end of the period, get them into separate tanks and keep them liquid
> >until the end of the period
>
> If one has to do LH as well, then your solution proposed above
> wouldn't work, per se.
>
Well, you'd need to add the dedicated hydrogen tanks at 50kg each. I
hadn't realized how heavy they were relative to the mass carried. Still
not a monsrously large payload.
> >I hope the intent is to include propellant transfer, since that's the
> >important problem. But the wording is ambiguous.
>
> It's *an* important problem, but it's not *the* important problem.
> There are a number of technologies to be developed (and which are
> apparently being given short shrift by NASA), including transfer,
> long-term storage, settling, ullage management, automated docking with
> fueling, etc.
How would you edit the challenge proposal to be more effective?
Will McLean
Rand Simberg
>> It's *an* important problem, but it's not *the* important problem.
>> There are a number of technologies to be developed (and which are
>> apparently being given short shrift by NASA), including transfer,
>> long-term storage, settling, ullage management, automated docking with
>> fueling, etc.
>
>
>How would you edit the challenge proposal to be more effective?
I can't answer that, until I've looked it over and thought about it,
something that I've unfortunately little time to do right now.
Dr John Stockton
dated Thu, 9 Feb 2006 09:50:13 remote, seen in news:sci.space.policy,
Will McLean <mclea...@aol.com> posted :
>
>(4) At least two weeks before the end of the Storage Duration in LEO,
>the Propellant Minimum Mass should be liquefied and stored in separate
>tanks as saturated liquids at 16 +/- 0.5 pounds per square inch
>(absolute) for the remainder of the Storage Duration.
>
>e. Deadline - January 1, 2012 (local date and time in Washington, D.C.,
>U.S.A.). The Deadline may be extended at the sole discretion of NASA.
>
>f. Low Earth Orbit - Any orbit around the Earth above the altitude of
>200 kilometers, aka LEO.
>
>g. Minimum Mass - At least 20 kg of liquid hydrogen and at least 120 kg
>of liquid oxygen.
Weird. Mass is in kilograms, altitude is in kilometres above an
unspecified datum, but they give the pressure in Imperial units !
Still, two out of three is progress.
And they don't actually say what time, 00:00 to 24:00, is the deadline.
--
© John Stockton, Surrey, UK. ?@merlyn.demon.co.uk Turnpike v4.00 MIME. ©
Web <URL:http://www.merlyn.demon.co.uk/> - w. FAQish topics, links, acronyms
PAS EXE etc : <URL:http://www.merlyn.demon.co.uk/programs/> - see 00index.htm
Dates - miscdate.htm moredate.htm js-dates.htm pas-time.htm critdate.htm etc.
Russell Wallace
> The most elegant solution would use a LH fueled upper stage, and use
> residual fuel for the LH demonstration as well. However, they aren't
> always going to LEO, and the people that launch them may be less
> cooperative about modifications to their stage. The 20 kg of LH
> required could use dedicated tanks.
Is hydrogen the best fuel for this job? I'm a programmer not an
aerospace engineer, but as I understand it, hydrogen is commonly used
for upper stages because it's lighter than anything else - but most
launchers don't need to store their upper stage fuel in orbit for long
periods of time. If you do need to do that, would something like propane
or kerosene be a better option?
--
"Always look on the bright side of life."
To reply by email, replace no.spam with my last name.
Rand Simberg
Wallace <russell...@gmail.com> made the phosphor on my monitor
glow in such a way as to indicate that:
>Will McLean wrote:
>> The most elegant solution would use a LH fueled upper stage, and use
>> residual fuel for the LH demonstration as well. However, they aren't
>> always going to LEO, and the people that launch them may be less
>> cooperative about modifications to their stage. The 20 kg of LH
>> required could use dedicated tanks.
>
>Is hydrogen the best fuel for this job? I'm a programmer not an
>aerospace engineer, but as I understand it, hydrogen is commonly used
>for upper stages because it's lighter than anything else - but most
>launchers don't need to store their upper stage fuel in orbit for long
>periods of time. If you do need to do that, would something like propane
>or kerosene be a better option?
It depends. The advantages of hydrogen are its high specific impulse,
and the fact that it's probably the easiest of all fuels to create off
planet (just crack water). The disadvantage is low density (which
tends to reduce the Isp advantage somewhat, since it requires larger
tanks), more difficulty of storage, and transfer (though those are
surmountable).
It's a trade, to which there is no obvious answer (despite the
religious entreaties of both sides of the debate), and the answer will
always depend on what figures of merit you choose to use.
I'm starting to tend to methane myself, but that's because I'm more
interested in asteroids than the moon (the latter makes more sense for
hydrogen, because making hydrocarbons requires imports).
Brad Guth
sooner the better), and it otherwise sucks if the massive size and thus
added inert/dry mass of what it takes for accommodating the likes of
such volumes of LOX/LH2 is a factor.
Does gross liftoff mass mean anything these's days?
If it does, then perhaps using LRBs instead of SRBs, and perhaps that
of the first core stage if not also the 2nd stage of h2o2/c3h4o are
just the best ever ticket to ride, with the LH2/LO2 as final 3rd stage.
H2O2/C3H4O (h2o2/c3h4o) does not suck because, it is compact and can be
efficiently stored as slush or even safely managed at relatively high
temperatures, and for next to forever at that.
BTW; the h2o2/aluminum makes for a really nifty energy battery
density.
-
Brad Guth
Will McLean
Russell Wallace wrote:
> Will McLean wrote:
> > The most elegant solution would use a LH fueled upper stage, and use
> > residual fuel for the LH demonstration as well. However, they aren't
> > always going to LEO, and the people that launch them may be less
> > cooperative about modifications to their stage. The 20 kg of LH
> > required could use dedicated tanks.
>
> Is hydrogen the best fuel for this job? I'm a programmer not an
> aerospace engineer, but as I understand it, hydrogen is commonly used
> for upper stages because it's lighter than anything else - but most
> launchers don't need to store their upper stage fuel in orbit for long
> periods of time. If you do need to do that, would something like propane
> or kerosene be a better option?
>
NASA has a hydrogen fueled upper stage engine in production. It has
flown to the moon using the J-2, and can put it back into production. A
propane or kerosene burning upper stage engine would be a significant
project.
Will McLean
Will McLean
Russell Wallace wrote:
> Will McLean wrote:
> > The most elegant solution would use a LH fueled upper stage, and use
> > residual fuel for the LH demonstration as well. However, they aren't
> > always going to LEO, and the people that launch them may be less
> > cooperative about modifications to their stage. The 20 kg of LH
> > required could use dedicated tanks.
>
> Is hydrogen the best fuel for this job? I'm a programmer not an
> aerospace engineer, but as I understand it, hydrogen is commonly used
> for upper stages because it's lighter than anything else - but most
> launchers don't need to store their upper stage fuel in orbit for long
> periods of time. If you do need to do that, would something like propane
> or kerosene be a better option?
>
Fred J. McCall
:I'm glad that they have a Centennial Challenges prize for a depot
:demonstration, but it seems ridiculously underfunded to me. Given
:current launch costs, how in the world do they think that anyone would
:be able to do it within an order of magnitude of five million? And if
:it turns out that someone can, it throws all of NASA's plans in a
:cocked hat, in terms of the implications for launch costs and orbital
:operations.
Uh, that's why it's a 'prize' and not a 'contract', Rand.
If they want to put enough money into the prize to fund it, what
they'll get is a one-off 'trick' just to claim the prize.
If they want to put enough money into the prize to fund it, they could
just hire someone to do it.
--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn
Rand Simberg
McCall <fmc...@earthlink.net> made the phosphor on my monitor glow in
such a way as to indicate that:
>simberg.i...@org.trash (Rand Simberg) wrote:
>
>:I'm glad that they have a Centennial Challenges prize for a depot
>:demonstration, but it seems ridiculously underfunded to me. Given
>:current launch costs, how in the world do they think that anyone would
>:be able to do it within an order of magnitude of five million? And if
>:it turns out that someone can, it throws all of NASA's plans in a
>:cocked hat, in terms of the implications for launch costs and orbital
>:operations.
>
>Uh, that's why it's a 'prize' and not a 'contract', Rand.
>
>If they want to put enough money into the prize to fund it, what
>they'll get is a one-off 'trick' just to claim the prize.
I didn't say they should put enough in it to fund it, just that they
shouldn't put in a trivial amount.
Brad Guth
serious rocket butt, such as utilizing LRBs of h2o2/c3h4o instead of
those inert massive SRBs gets zilch worth of a Usenet responce.
Apparently getting the most payload per launch into space isn't such a
big deal after all. It's just another brown-nosed game because of whom
gets all of the bucks for having provided the LOX/RP-1 and LO2/LH2
that's first stage wossy and even 2nd stage inferior to the h2o2/c3h4o
alternative.
Are those two elements on the taboo/nondisclosure (aka need-to-know)
list?
-
Brad Guth
Brad Guth
Flannery" would have to totally agree with whatever spook "Me" had to
contribute;
:stupid and/or meaningless questions which are irrelevant
:and/or answered with a 5-minute search on Google .
So, of whatever's Saturn-V ice-loading and of various mass totals are
"irrelevant" in rocket-science, just like their rocket/payload ratios
and of the inert/dry mass factors are supposedly "irrelevant",
especially if such info pertains to anything NASA/Apollo. Therefore
you folks can't be the least bit bothered to so much as answer upon
these five relatively simple questions that are NOT as your
disinformation and evidence exclusionary crapolla stipulates as
available within any "5-minute search on Google". Why am I not the
least bit surprised that the CEV fiasco is going to take considerably
more than a best all-out effort of any modern day 60:1 ratio that
probably can't hardly manage GSO, and that's with disposable composite
SRMs and using every other fly-by-rocket trick in the book.
In addition to all of the pretentious arrogance and that of the usual
ongoing intellectual as well as biological bigotry as to global
warming, of the perpetrated cold-war(s), and otherwise as to what folks
obviously can't accept as to the 6-Day war and USS LIBERTY fiasco, or
that of the "KAL007 Coldwar Mystery", "911" or "WMD", and since no one
that's taken seriously within thus Usenet from hell really gives a
flying hocky puck as to the reality of global warming or even as to our
local environmental and badly sluffing geophysics fiasco plus ocean
thermal expansion factors that's adding further environmental insult to
injury. As such, I'll add five simple questions for the old
NASA/Apollo (aka MI6/NSA~CIA) gipper of brown-nosed minions and spooks
to answer: (though bet they can't)
Because of what LO2/LH2 represents, and that we're talking about
substantial surfaces that were wsustained ell below freezing, whereas
at least for most all of the first two stages of the Saturn-V launch
phase had to have been packing along a considerable amount of ice
tonnage. After all, the Saturn-V(Saturn 5) was essentially an
absolutely impressive 2-stage deployment of getting considerable
tonnage into LEO, whereas some of that initial tonnage had to have
represented a substantial amount of ice loading. Aparently their
LOX/RP-1 application was actually nearly twice as good as reported,
thus no need for LRB's of h2o2/c3h4o.
Why is there no information as to the amount of Saturn-V ice loading?
Why are the gross liftoff tonnage figures reported as all over the
place?
Why is there even a kg difference as to the mass of each phase and of
the totals?
Why is the tonnage and velocity as deployed past LL-1 not perfectly
clear as a "Chapel Bell"?
Why is there no mention of LL-1 or ME-L1 or EM-L2 as associated
rocket-science or satellite station-keeping information tagged along
with anything that's NASA or Apollo?
-
Brad Guth
Michael Kent
> So that's how we got Constellation (although I'd prefer EELV-derived
> launch systems, that's really just a small detail in the big picture).
A small detail in the big picture, perhaps, but a very large one in
the current budget mess. When first proposed, the VSE came with a
$1 billion / year plus-up to the NASA budget. That's enough to pay
for the $5 billion CEV in five years, which is the amount of time NASA
had until the Shuttle would be retired.
What the VSE didn't come with was a big enough plus-up to fund the Stick.
That extra $5 billion development is what is blasting holes in the aero-
nautics, science, Shuttle, and Station budgets. Without the Stick there
wouldn't be nearly the opposition in Washington that there is now.
Mike
-----
Michael Kent Apple II Forever!!
St. Peters, MO
mic...@syndicomm.remove.this.com
Michael Kent
> In article <1139247512.1...@g43g2000cwa.googlegroups.com>,
> Will McLean <mclea...@aol.com> wrote:
>>However, there's nothing about the *CEV* design that precludes a
>>significantly different misssion profile
[snip]
> A system designed from the start for sustained long-term operations would
> look quite different.
I'm becoming increasingly convinced that ESAS is not *intended* to lead
to long-term lunar operations. I think it's pretty obvious from watching
the agency the last 20 years that NASA really really wants to go to Mars.
Up until now, they haven't been allowed to. But under the VSE, they can
go to Mars, but they must finish the Station and go back to the moon
first.
NASA responded to these priorities by studying what the absolute minimum
was to satisfy the requirement to "finish the Station" so they could
retire the Shuttle and go to the moon. I'm convinced that as soon as
the first landing is done they will say "We've fulfilled the President's
requirement -- now on to Mars!"
Rand Simberg
mic...@syndicomm.remove.this.com (Michael Kent) made the phosphor on
my monitor glow in such a way as to indicate that:
>> A system designed from the start for sustained long-term operations would
>> look quite different.
>
>I'm becoming increasingly convinced that ESAS is not *intended* to lead
>to long-term lunar operations. I think it's pretty obvious from watching
>the agency the last 20 years that NASA really really wants to go to Mars.
>Up until now, they haven't been allowed to. But under the VSE, they can
>go to Mars, but they must finish the Station and go back to the moon
>first.
>
>NASA responded to these priorities by studying what the absolute minimum
>was to satisfy the requirement to "finish the Station" so they could
>retire the Shuttle and go to the moon. I'm convinced that as soon as
>the first landing is done they will say "We've fulfilled the President's
>requirement -- now on to Mars!"
That's called the "touch and go" philosophy. I'm not sure that it's
what's driving the current architecture, but it could be.
Either way, it won't be sustainable, and will come to tears, as Apollo
did.
Monte Davis
>That's called the "touch and go" philosophy.
Hadn't heard that one before, but I like it -- as pithy as "flags and
footprints."
Douglas Holmes
"Michael Kent" <mic...@syndicomm.remove.this.com> wrote in message
news:cfQJf.12$WZ4....@news.more.net...
> Brian Thorn <btho...@cox.net> wrote:
>
>> So that's how we got Constellation (although I'd prefer EELV-derived
>> launch systems, that's really just a small detail in the big picture).
>
> A small detail in the big picture, perhaps, but a very large one in
> the current budget mess. When first proposed, the VSE came with a
> $1 billion / year plus-up to the NASA budget. That's enough to pay
> for the $5 billion CEV in five years, which is the amount of time NASA
> had until the Shuttle would be retired.
>
> What the VSE didn't come with was a big enough plus-up to fund the Stick.
> That extra $5 billion development is what is blasting holes in the aero-
> nautics, science, Shuttle, and Station budgets. Without the Stick there
> wouldn't be nearly the opposition in Washington that there is now.
>
You hit the nail on the head.
Not only was it originally supposed to be EELV based but take to 2014.
At the very least the EELVs could have handled the unmanned tests unchanged.
With the compressed schedule this would have saved millions if not billions
over the next several years.
The Stick IMO has the potential to kill or seriously harm this whole
program.
Even more then before since it now needs both an unflown larger solid
and a brand new upper stage of which the largest part is an engine
that has yet to be built or tested.
All the while NASA keeps saying the reason to use it is that it is
a proven system. It is this kind of logic that can kill astronauts.
Jeff Findley
"Douglas Holmes" <noholme...@verizon.net> wrote in message
news:jz1Kf.3005$GQ.2768@trnddc03...
> The Stick IMO has the potential to kill or seriously harm this whole
> program.
> Even more then before since it now needs both an unflown larger solid
> and a brand new upper stage of which the largest part is an engine
> that has yet to be built or tested.
To be fair, the J-2S has been built and tested, but that was literally
decades ago:
http://www.astronautix.com/engines/j2s.htm
The most recent notes (from the above web page) on this engine are:
It was estimated by ATK Thiokol in 2005 that restarting the J-2S
program,
including engine fabrication, design and reliability verification,
certification, and production, would require four years. Although no
J-2S
tooling was known to exist, modern soft tooling could be developed
quickly and less expensively than the original hard tooling. There was
an
existing manufacturing and supplier network in place to support a J-2S
restart.
> All the while NASA keeps saying the reason to use it is that it is
> a proven system. It is this kind of logic that can kill astronauts.
I doubt that, given the J-2S lineage, but it certainly has the potential to
increase development time and cost for The Stick if any development problems
are encountered.
Jeff
--
Remove icky phrase from email address to get a valid address.
Brad Guth
Obviously I can see that some Usenet spook pulled entirely out of the
CEV on a stick moon-race.
It must have been something to do with the supposed better than 60:1
liftoff/payload ratio of their inert massive hocus-pocus Saturn-V
that's running seriously amuck.
Either that or it's having to do with those far better and thus nifty
LRBs using h2o2/c3H4o.
Sorry about that.
-
Brad Guth