Mostly turkish, some serbo- croatian and albanian (immigrants from Kosovo and Bosnia) as well as arabic, turkish is by far the leading language though (I think some 18% of the German population speaks turkish at least in addition to German).OK, now I'm curious. What do they speak?
F-22 production termination is premature
@Skipjack:
I think our disagreement is largely philosophical.
I believe substantial improvements to LEO access are not going to happen if we simply focus on LEO. We need to have a reason beyond just microgravity research and spy satellites. If we confine ourselves to LEO because "it's too expensive", it will always remain too expensive, and human spaceflight will stagnate.
(Barring development of an aerospace-class Polywell, of course. Also, Reaction Engines might pull off a miracle and break the cost-to-LEO barrier - but unfortunately their approach doesn't scale well to exploration hardware.)
I think it's dangerous to get too excited about the shiny NewSpace stuff. It's very likely to either fizzle completely or not have the desired impact. Putting off our exploration plans to wait on the new! dynamic!! upstarts will probably end in disappointment.
I believe NASA's HSF side is salvageable, and that your disgust with it is unfair to the workers and engineers who have been shafted by the bureaucracy and upper management. I think we should work with what we have rather than firing everybody and starting over.
Though it's looking increasingly like NASA HSF is headed straight for a brick wall, deliberately ignoring any good options. You may get your wish, regardless of what either of us thinks.
Nonetheless, I will engage in one more round of point-counterpoint, just because I can:
If I'm not mistaken, the CF-105 Arrow Mark IIA had greater predicted speed and range while supercruising than the F-22 Raptor. Which one do you think is/was the more advanced vehicle? Dumb question, right?
Also, IIRC, apparently the delta-V required for a reusable single-stage lunar lander (that doubles as an ascender) is roughly what would be required to do a mostly-propulsive landing on Mars...
I'm hoping he is wrong this time; that would be great.
On the other hand, SpaceX did present a plan to the Augustine Commission for a heavy lifter in the Saturn V class that would cost $2B to develop. If there was any guarantee that this was not wildly optimistic (there has to be a reason it never showed up in the public debates), I would be in favour of that, since it costs so much less than even Jupiter, never mind Ares... of course, there's the question of how long it would take...
But if it were chosen now, there could be test flights in early 2013.
If it had been chosen at ESAS (something very like it was going to be until Griffin "leaned on" the results), it would be flying now.
Let's see SpaceX beat ULA in a race to get a high-performance cryogenic upper stage fielded. Start them at the same time (on a fixed-price contract, of course), and see if the Raptor stage can hold a candle to the ACES-41 in either performance or timeliness.
Apparently if PWR could sell RL-10s fast enough, they would only cost about as much as a helicopter turbine, or a reasonably nice car.
The problem with RLVs is that they are very expensive. More expensive than ELVs. To get the cost down, you need a high flight rate. And since you don't start off with a high flight rate, you price to the market you have. Killing the chance of a bigger one. It ends up not being worth the development cost.
Even Skylon has to capture almost the entire world launch market to get its costs down below those of SpaceX. The further dramatic reductions would be due to this 'foot in the door' resulting in market growth - ie: people realizing that they already own a Skylon and that flying it each time is pretty darn cheap...
Are we sure there's even enough to do in LEO to get the costs down, if we're not going to be exploring?
EDIT: corrected CF-105 Mk. II reference; the 'A' variant is the one with the predicted 700+ nm radius with supersonic flyout at Mach 1.8, supersonic combat at up to Mach 2.4, and subsonic return...
I think our disagreement is largely philosophical.
I believe substantial improvements to LEO access are not going to happen if we simply focus on LEO. We need to have a reason beyond just microgravity research and spy satellites. If we confine ourselves to LEO because "it's too expensive", it will always remain too expensive, and human spaceflight will stagnate.
(Barring development of an aerospace-class Polywell, of course. Also, Reaction Engines might pull off a miracle and break the cost-to-LEO barrier - but unfortunately their approach doesn't scale well to exploration hardware.)
I think it's dangerous to get too excited about the shiny NewSpace stuff. It's very likely to either fizzle completely or not have the desired impact. Putting off our exploration plans to wait on the new! dynamic!! upstarts will probably end in disappointment.
I believe NASA's HSF side is salvageable, and that your disgust with it is unfair to the workers and engineers who have been shafted by the bureaucracy and upper management. I think we should work with what we have rather than firing everybody and starting over.
Though it's looking increasingly like NASA HSF is headed straight for a brick wall, deliberately ignoring any good options. You may get your wish, regardless of what either of us thinks.
Nonetheless, I will engage in one more round of point-counterpoint, just because I can:
I'm not in favour of the current Constellation architecture. DIRECT works differently; the heavy lifter is also the crew launcher, just with an extra SSME and a commercially-developed upper stage.Skipjack wrote:That may be true, but the corrent Constellation architecture does not require just a heavy lifter. Crews would not be launched on AresV but on AresI. They could be launched much more savely with an RLV, which could also support the station. What use is an expolation vehicle if you cant support it with a crew for a reasonable price?However, I don't think they constitute a replacement for a heavy lifter. Exploration spacecraft cost more than their launchers, by a sizeable factor.
That would be great. But you've got to start somewhere, and making stuff reusable that we're not even sure how to make expendable any more is a bridge too far IMO. One step at a time.Also, with an architecture that prefers infrastructure over speed of development, part of the exploration architecture could be fully reusable. E.g. a shuttle between Lunar Orbit and LEO, could be reusable and be refueled with fuel from the moon (with low enough cost to LEO also with fuel from earth). You said it yourself that the exploration vehicles are expensive. So why throw them away every time?
Ablative TPS is also pretty mature, and reusable TPS is not feasible for lunar return velocity. Everything else that you mention is vastly improved in Orion as opposed to Apollo. Did you know that Orion is supposed to be able to launch, insert itself into orbit, approach the ISS, and dock without the crew having to lift a finger?That is not the only area where advancements can be made. Weight savings can be achieved by employing new technology for structural and TPS- materials, e.g. Newer, more lightweight computer technology also helps saving weight and space (sure it is not THAT much, but a bit).The fact is that chemical rocket technology is mature; it hasn't advanced all that much since Apollo, and it won't get substantially better than it is now no matter how long you wait.
If I'm not mistaken, the CF-105 Arrow Mark IIA had greater predicted speed and range while supercruising than the F-22 Raptor. Which one do you think is/was the more advanced vehicle? Dumb question, right?
DIRECT is a much more flexible architecture that could easily allow reusable spacecraft. The depot infrastructure that characterizes Phase III could readily be extended to maintaining reusable lunar landers; there's been plenty of discussion along these lines in the DIRECT threads on nasaspaceflight.Also, why has pretty much all development on the aerospike engines been stopped (other for a small college programme)?
Also, the shuttle was at least partially reusable. The constellation architecture wont be reusing anything (maybe refurbishing the Orion capsules, which will save close to nothing). DIRECT does not change this either.
Also, IIRC, apparently the delta-V required for a reusable single-stage lunar lander (that doubles as an ascender) is roughly what would be required to do a mostly-propulsive landing on Mars...
Commercial providers, of course. Even with the J-130 available, DIRECT hands off the ISS to them as quickly as possible, except for the occasional outsize module or ORU.And how are you planning on bringing crews and supplies to the ISS?If we're not going to do exploration, there's not much point developing Jupiter, now is there?
No one but Mike Griffin wants the ISS splashed in 2016. Almost certainly it will go to at least 2020. Much past that and you're pushing its design lifetime, though if it's popular enough I'm sure they'll come up with something...With the current planning the ISS will be destroyed - prematurely if you ask me. Why is that? Not because it would not be needed anymore, but because with the current plans, it will be to expensive to maintain it.
The industry veteran I'm thinking of is a very well respected poster on nasaspaceflight.com. He's a bit of a wet blanket, but he's basically never wrong unless he's misunderstood the question.Yeah, of course they feel that way. They are protecting their corporate butts.Space industry veterans tend to feel that SpaceX hasn't really felt the bite of all the overhead that goes with operating a major launch business yet, and that once they do, their costs will go up, not down.
I'm hoping he is wrong this time; that would be great.
Not true. SpaceX has had significant funding from DARPA, and NASA provides about 80% of SpaceX's external funding. Also, the resupply contract is a few billion, not a few million.Ahem, at much smaller budget: Full Falcon 9 flight- hardware at the cape, test Dragon hardware at the cape. Full Falcon 9 first and second stage ground tested. Launch in a few months from now.If DIRECT is selected, NASA and its OldSpace contractors will be able to make Jupiter fly, safely and routinely - and soon. SpaceX hasn't demonstrated anything yet as regards a launch vehicle the size of Falcon 9
All that has not cost NASA a single dime yet (other than the few millions for the resuply contract, which is also milestoned).
On the other hand, SpaceX did present a plan to the Augustine Commission for a heavy lifter in the Saturn V class that would cost $2B to develop. If there was any guarantee that this was not wildly optimistic (there has to be a reason it never showed up in the public debates), I would be in favour of that, since it costs so much less than even Jupiter, never mind Ares... of course, there's the question of how long it would take...
Too much, and hopefully never. I don't want NASA to get stuck with Ares I for the next 30 years...How much has constellation cost so far? When is that going to fly?
Unfortunately, it looks like never. Bolden's internal study has ignored the J-130 yet again. In fact, DIRECT has gotten ahold of the materials generated by the study and are claiming it's another hatchet job.When is DIRECT going to fly?
But if it were chosen now, there could be test flights in early 2013.
If it had been chosen at ESAS (something very like it was going to be until Griffin "leaned on" the results), it would be flying now.
OldSpace refers to Boeing, Lockheed Martin, ATK, PWR, etc. Commercial space companies, the lot of them. NASA hasn't designed a launch vehicle in 30 years, and the people there now have mostly never done it before. But Griffin insisted on MSFC being the design house...So far SpaceX has achieved a lot more than what has been achieved by the OldSpace guys for constellation.
We will see whether whatever they will build will fly any time...
Let's see SpaceX beat ULA in a race to get a high-performance cryogenic upper stage fielded. Start them at the same time (on a fixed-price contract, of course), and see if the Raptor stage can hold a candle to the ACES-41 in either performance or timeliness.
Apparently if PWR could sell RL-10s fast enough, they would only cost about as much as a helicopter turbine, or a reasonably nice car.
There's no proof at all that they will come if you build it. That's why almost no one is seriously attempting development of an RLV. The STS was designed and sold based on this very principle; it wasn't entirely the fault of the refurbishment-intensive design that no one lined up to launch stuff on STS.The typical chicken before the egg argument.
If you build it, they will come. Even suborbital flights have a market, if they are cheap enough, as we have learned recently.
The problem with RLVs is that they are very expensive. More expensive than ELVs. To get the cost down, you need a high flight rate. And since you don't start off with a high flight rate, you price to the market you have. Killing the chance of a bigger one. It ends up not being worth the development cost.
Even Skylon has to capture almost the entire world launch market to get its costs down below those of SpaceX. The further dramatic reductions would be due to this 'foot in the door' resulting in market growth - ie: people realizing that they already own a Skylon and that flying it each time is pretty darn cheap...
Are we sure there's even enough to do in LEO to get the costs down, if we're not going to be exploring?
EDIT: corrected CF-105 Mk. II reference; the 'A' variant is the one with the predicted 700+ nm radius with supersonic flyout at Mach 1.8, supersonic combat at up to Mach 2.4, and subsonic return...
Last edited by 93143 on Sun Nov 29, 2009 8:12 pm, edited 1 time in total.
I agree, that we have to go beyond LEO, at least to some extent (though I think there is plenty of market in LEO as well).I believe substantial improvements to LEO access are not going to happen if we simply focus on LEO. We need to have a reason beyond just microgravity research and spy satellites. If we confine ourselves to LEO because "it's too expensive", it will always remain too expensive, and human spaceflight will stagnate.
However getting cargo and crews to LEO has to be cheap first of all. Then we can go from there via orbital fuel depots, etc to anywhere.
I agree on the need for orbital depots btw. That is part of the in space infrastructure that I would be building.
Once transport to LEO via RLVs has become relyable enough, bringing nuclear reactors into space for long distance missions will be politically easier to get through.
And really for anything beyond LEO there is currently no path past nuclear engines. You might be able to do the moon without them but not in a fashion that is sustainable.
It is not my wish. Dont get me wrong. I was being pessimistic.Though it's looking increasingly like NASA HSF is headed straight for a brick wall, deliberately ignoring any good options. You may get your wish, regardless of what either of us thinks.
I prefer Jupiter over Ares1 and AresV, no question about it. But I dont think that NASA can do Jupiter. That is my problem. I just have lost all trust in NASA being able to build a launcher. Even in them being able to fund and oversee development of a launcher.
Yeah, only that I would not go directly from the Moon back to the ground. I would switch vehicles in earth orbit. Then you dont need the ablative TPS. Actually the vehicle that shuttles between earth orbit and lunar orbit would not need a TPS at all.Ablative TPS is also pretty mature, and reusable TPS is not feasible for lunar return velocity.
That was my way of thinking.
So you would do as much as possible with the LEO- RLV and then have purpose built vehicles for certain tasks.
Just like you dont fly your car across the atlantic. You drive your car to the airport and then switch on the airplane to go across the atlantic.
The LEO- RLV would be the car and the lunar shuttle the airplane.
One is cheap and has a higher usage rate. The other one (still) costs a little more but is cheaper for the mile traveled.
Yeah, but how much money was the funding from DARPA and NASA so far? The award of the resupply contract is comparably new. They have not gotten the money yet, or have they? I think it is per launch.Not true. SpaceX has had significant funding from DARPA, and NASA provides about 80% of SpaceX's external funding. Also, the resupply contract is a few billion, not a few million.
So they still have to launch first.
How many billions has the paper rocket Ares cost NASA so far? With no hardware built yet. And no, Ares 1X does not count. If that counts then Falcon 1 counts too. The latter at least uses the same engine as Falcon 9 does.
There's no proof at all that they will come if you build it.
Virgin Galactic.
Until they came, noone believed there was a market for suborbital flight. Now it is a whole new industry and a growing one too, with competitory entering the market as well.
The entire "current" world launch market. Once cheap relyable launchers become available, more customers will appear on the scene. There is a very small market for Plasma TVs that cost 100k, but a big market for Plasma TVs that cost 1k.Even Skylon has to capture almost the entire world launch market to get its costs down below those of SpaceX.
Space is big, there is lots of stuff to be discovered in space. Once in LEO, you are halfway to anywhere.Are we sure there's even enough to do in LEO to get the costs down, if we're not going to be exploring?
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We know how to make spaceships and crap--big metal or plastic airtight tube, insulated, maybe some radiation shielding depending.That would be great. But you've got to start somewhere, and making stuff reusable that we're not even sure how to make expendable any more is a bridge too far IMO. One step at a time.

The big problem is that you have to actually build it, then test it, then launch it, then do a bunch more checks, etc. And at this stage of the game, you get the chicken and egg problem even worse--if you guys are complaining about the market to LEO, how about Lunar orbit?

The fundamentals of design are known. We haven't reapplied them. Well, a few have, but nothing's gotten off paper, because due to launch costs, they're too expensive right now. Of course, that brings us around to the circular argument.
Evil is evil, no matter how small