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#26 2004-06-03 17:39:27

Ian Flint
Banned
From: Colorado
Registered: 2003-09-24
Posts: 437

Re: STOP PRESS: Scaled announce launch date

That was the reasoning behind Concorde.  Sales were lower than expected, and Concorde was not profitable.  The space plane would probably be much more expensive and dangerous than Concorde, and only a little faster.

Ah, but Concord didn't let you see the Earth from above the atmosphere or give you a few minutes of zero-g to play in.  And, Concord was restricted to trans-Atlantic flight (I think) because of low altitude sonic booms.  The sonic booms of the spaceplane would be at very high altitude.

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#27 2004-06-03 23:17:33

Rxke
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From: Belgium
Registered: 2003-11-03
Posts: 3,669

Re: STOP PRESS: Scaled announce launch date

Another very important killing Concorde setback was that it was not allowed to fly over densely populated regiions "because of the noise," so no good airports connection like NY.... Making a fast flight insignificant because of time wasted on the ground travelling to the big cities..
Britons/French say this was purely politics (Boeing Lockheed etc behind the curtains)

But what i'm impressed with mainly is the cost of SSO/White Knight: what they're doing is a fraction of the cost of X-15/B-52 or the first suborbital rockethops... Using modern tech, materials. That's the main lesson learned IMO.

Being unimpressed is being cynical. ANY one interested in avionics/spaceflight can't be honestly unimpressed by what they're achieving here.

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#28 2004-06-03 23:56:14

Euler
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From: Corvallis, OR
Registered: 2003-02-06
Posts: 922

Re: STOP PRESS: Scaled announce launch date

Another very important killing Concorde setback was that it was not allowed to fly over densely populated regiions "because of the noise," so no good airports connection like NY.... Making a fast flight insignificant because of time wasted on the ground travelling to the big cities..
Britons/French say this was purely politics (Boeing Lockheed etc behind the curtains)

New York initially banned Concorde flights, but stopped in 1977.  Concorde was doing New York-London flights for more than 25 years.

But what i'm impressed with mainly is the cost of SSO/White Knight: what they're doing is a fraction of the cost of X-15/B-52 or the first suborbital rockethops... Using modern tech, materials. That's the main lesson learned IMO.

Being unimpressed is being cynical. ANY one interested in avionics/spaceflight can't be honestly unimpressed by what they're achieving here.

I am unimpressed.  The difference between an x-prize class suborbital spacecraft and an orbital spacecraft is at least as large as the difference between the Wright brothers' airplane and a supersonic jet.

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#29 2004-06-04 02:45:41

Hazer
Member
From: Texas/Oklahoma
Registered: 2003-10-26
Posts: 173

Re: STOP PRESS: Scaled announce launch date

Perhaps the difference isn't so large, maybe the difference between a ME-262 and a F-14.
Needless to say, unless the current Moon-to-Mars program gets it's rear in gear, something like this may be the beginning of a series of events that gets us to Mars.
Honestly--does anyone expect the collective Space Agencies of the world to wake up one morning and decide to do something along the lines of Marsdirect?


In the interests of my species
I am a firm supporter of stepping out into this great universe both armed and dangerous.

Bootprints in red dust, or bust!

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#30 2004-06-04 09:06:41

GCNRevenger
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From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: STOP PRESS: Scaled announce launch date

Well in short Hazer, the answer is "no," there is no "maybe" about it that the difference in performance and minimum requisit complexity for a suborbital and an orbital vehicle is very great.

The SS1/WH setup can achieve speeds in the low Mach number region well under Mach five, and that is using most of its airspeed to climb to about half way to a useable orbital altitude. An orbital vehicle needs to reach Mach TWENTY Five of horizontal ground speed, not airspeed, AND reach DOUBLE the height in the process. And how will you get back down? You need an RCS system for attitude control, you need a reliable and reuseable heat shield, you need thermal insulation for the rest of the vehicle, you need stronger wings to handle Mach-20+ conditions, you need a powerful air conditioning system, and of course you need a reliable OMS engine for deorbiting, and certainly many things I haven't mentioned... Orbital flight is so much harder than Burt or Carmak make it seem that its laughable.

And as the DC-X program goes... even if it met its very optimistic mass estimates (which I have doubts), its maximum payload would still be pretty small (~10MT), and the vehicle itself would cost several billions of dollars ($6-7Bn est) to make, AND has never done more than hover a few hundred feet... to say nothing of its slightly crazy reentry scheme. Build one privatly? Not a chance...

And as far as "incrimental" development to orbit... again I say, that isn't going to happen no matter how hard you wish it. There is no market for a small and fairly dangerous vehicle with a very long lead time for high-speed intercontenantal travel. None. If it takes more than hours to prepare for flight from the order, then you might as well just take a regular airliner. Its too hazardous for everyday flights, corperations will not put money into such a thing as a customer (our CEO died today in a plane crash, again, for the third time) or will insure such a vehicle. The demand for faster business travel will not be met by a little cheap space ship.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#31 2004-06-04 09:19:23

clark
Member
Registered: 2001-09-20
Posts: 6,362

Re: STOP PRESS: Scaled announce launch date

LOL!

GNC, don't ever give up!

You say 10MT is too small, yet in your post prior to that, you say 10MT is enough!   :laugh:

The DC-X is estimated at 2-5 billion. Not 6-7 billion. The technology exsisted in the 90's. It's sitting on shelfs now. We've made strides in the material sciences to deal with the heat shield issues (which were developed for all of those 2nd and 3rd generation shuttle replacements). While the reentry concept is screwy for the DC-X, most agree it would have reentered tail first, instead of doing that little sumersault.

It was being designed to use either an aerospike or bell shaped engines- multiple engines to allow for successful orbital insertion even with rocket failure. Hover capability to burn off excess fuel in case of an abort.

It could be built privately as all seperate technology components have been proven on various other rockets. It's just a matter of integration and scaling up the design. The hover tests you poo-poo was designed to test the basic landing scheme, which was VTOL- perfect for any commercial spaceport that are now being developed. Again, the DC-X dosen't have to be SSTO, it could be designed as a TSTO launched on a cheap reusable first stage (which should improve the mass ratio to orbit).

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#32 2004-06-04 10:00:55

dicktice
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From: Nova Scotia, Canada
Registered: 2002-11-01
Posts: 1,764

Re: STOP PRESS: Scaled announce launch date

Euler: You wrote: "I am unimpressed. The difference between an x-prize class suborbital spacecraft and an orbital spacecraft is at least as large as the difference between the Wright brothers' airplane and a supersonic jet." Now, be honest: If you had witnessed from the tram running alongside that field, from 1904 onwards, the Wright Brothers teaching themselves how to operate that beast of a first three-axis-control "flying machine" in history, would you not have been impressed? Many weren't, it seems, and I think it was because, in that one aircraft (the Wright Flyer), they had solved all the problems that had prevented the rest of humanity from flight, since time began. Same as with balloons and dirigibles: Once proven to work, the way becomes obvious how to go about making further improvements, to enlarge and impove upon what these true innovators had begun from scratch. Burt Rutan, in my opinion, is in the process of proving what is tantamount to what the Brothers Wright did, back then: In this case, the invention of the first successful proof-of-concept flyback launching system leading to practical spaceflight. Similar to the Wright Flyer--once airborne out of ground effect, the pilot could in principle take it to any height he dared within the atmosphere--Rutan's SpaceshipOne isn't limited in principle to any height above the atmosphere. Both impressive inventions are unique in the on-going history of transportation: later to be reconfigured and endlessly improved upon after the fact by commercial as well as military interests, waiting--as I say--in the wings.

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#33 2004-06-04 10:34:18

GCNRevenger
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From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: STOP PRESS: Scaled announce launch date

Did I say that 10MT was -too- small? Nooo, i'm just saying that its pretty small, and isn't quite as big as current launchers. For the reccord, the DC-I was planned to have a 9MT capacity plus two crew, so I think it fair to assume a 10MT max unmanned payload.

And I disagree with you that it would be so inexpensive, I can't imagine it costing under $6Bn ($5Bn in 1991 dollars) to go from dinky hover & tank testbed to giant mega 40M tall and 12M wide production model with heat shield and all... nah, ain't gonna happen privatly unless you get His Billness to chip in.

The DC-I was also going to have a single aerospike version of the old J-2 engine... no engine out capacity there, and an engine that doesn't exsist. The DC-Y was going to use clusters of old RL-10's, and would only be a testbed.

And I agree that the heat shield is possible, but will take some doing to make the thing come back down tail-first... thats, like, uh, where the engine is and the landing gear and such.

Putting a "cheap reuseable first stage" on it would be the kiss of death for its supposed super ultra high simplicity of launch, because staged rockets aren't. Stage recovery, stage refurbishing, stage recertification, stage reintegration, stage testing... See "Shuttle SRB"

Again, as far as the Wright Brothers ---> Burt Rurtan goes, they didn't have as big a challenge to meet. Little proof of concept design that is hundreds of times too small and a hundred times less complex than a practical vehicle is of very dubious usefulness in my book. Getting into space is hard. Real hard. Its not anything like building airplanes, be they made of fabric and cloth powerd by motorcycle engines or out of carbon composists and powerd by a rocket engine.

Oh and as far as sending up two DC-I's, one with payload and one with fuel, 10MT of fuel minus docking and fuel transfer hardware isn't going to get you anywhere, especially since the stuff would boil off (LOX/LH). For goodness sakes, just use a kick stage and a bigger launcher.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#34 2004-06-04 10:48:04

clark
Member
Registered: 2001-09-20
Posts: 6,362

Re: STOP PRESS: Scaled announce launch date

And I disagree with you that it would be so inexpensive, I can't imagine it costing under $6Bn ($5Bn in 1991 dollars) to go from dinky hover & tank testbed to giant mega 40M tall and 12M wide production model with heat shield and all.

And therein lies the problem, you can't imagine it.  big_smile
It cost 200 million to put together the scale model, doing stuff that hadn't been done before. 2 Billion is a factor of 10 for a full scale, 4 billion is a factor of 20. I can't imagine it costing mroe than 5 billion.  tongue

The DC-Y, latter to become the Delta Clipper, was going to use multiple engines for engine out capability- we've had a decade of experience with the RL-10's so it dosen't need to be a test bed for those engines. We can just use them.

Coming down tail first isn't a big deal since the ship weighs 1/10 on return. Hell the Shuttle has it's landing gear on the belly two, so what's the difference here? The engines can be used to slow decent, or protected behind the heat shield during reentry. I fail to see any major barrier here.

Putting a "cheap reuseable first stage" on it would be the kiss of death for its supposed super ultra high simplicity of launch, because staged rockets aren't. Stage recovery, stage refurbishing, stage recertification, stage reintegration, stage testing... See "Shuttle SRB"

Perhaps, but I think there can be some solutions. Multiple first stages (As in more than 10) allows for the lead time related to refurbishing and all that other crap. And any comparison to how we do things with the Shuttle is just lame, any follow up to the Shuttle needs to learn from the mistakes of the Shuttle- which include how refurbishing is handled. Assuming that we would simply repeat the same process without improvement boggles the mind. If we did, then yeah, I would agree, but improvements can be made. Major improvements haven't been made because of the structural design of the Shuttle- they can only do so much.

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#35 2004-06-04 11:06:18

GCNRevenger
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From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: STOP PRESS: Scaled announce launch date

$5Bn? Now you are starting to talk some sense... where exactly do you intend to get these billions of dollars, for a vehicle that can't lift current satellites, for which there is very little market? Space tourism? I don't think there is enough money in that business either. Angel investors are not a credible form of income either.

I think you are a liiiitttle confused on which vehicle is which... the DC-Y was going to be an orbital testbed, 20M tall, about 1/10th as heavy, using a variation on the old RL-10 engines that trades Isp for thrust. The DC-I, the "Delta Clipper," is not the DC-Y; its ten times as heavy and 40M tall, using a lone new aerospike engine based loosely on the Saturn-V's J-2. It would take too many RL-10's to power the DC-I, that just won't happen, too many things to go wrong and too many things to have to service.

And as far as reentry, again, you are talking big money to make the vehicle reentry-proof like that... using engines for slowing down, I don't like that option at all. Stick with the heat shield and aerobraking.

So you say that a reuseable stage will be "really not like Shuttle SRBs, easy and cheap"? Ah huh. Why? Why would it be any easier or cheaper relativly speaking than Shuttle's boosters? How would it be cheaper? We already have learned quite a bit from Shuttle, but that doesn't mean that what we've learned makes it any easier! Now you want to go and recover a liquid fueled engine and fly it multiple times? You have to test the electronics, tank integrity, engine gimbals, turbopump, landing mechanism, and several other things often besides the cost of simply remating it to the upper stage and testing the assembled vehicle. Its not that easy.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#36 2004-06-04 11:55:07

dicktice
Member
From: Nova Scotia, Canada
Registered: 2002-11-01
Posts: 1,764

Re: STOP PRESS: Scaled announce launch date

GCNR: You wrote--
"Again, as far as the Wright Brothers ---> Burt Rurtan goes, they didn't have as big a challenge to meet. Little proof of concept design that is hundreds of times too small and a hundred times less complex than a practical vehicle is of very dubious usefulness in my book."

Yep, that's exactly right: They had/have what was/is too small and complex to go all the way: That's were the genius lies in my book--the basic, optimum, affordable first step that points the way to the future--the "hard" stuff to follow being literally impossible without that first step.

You also wrote--
"Oh and as far as sending up two DC-I's, one with payload and one with fuel, 10MT of fuel minus docking and fuel transfer hardware isn't going to get you anywhere, especially since the stuff would boil off (LOX/LH)."

Right again. But if your fuel vehicle carried a cargo of water-ice you could store it indefinitely and, when wanted, refuel by electrolysis and liquify the oxygen and hydrogen in space, without loss.

And you mentioned: "It ain't that easy" to work in orbit. We're talking about the future here. Isn't working hard in space what spacemen are supposed to do, up there? Sounds like an interesting and exciting occupation to me.

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#37 2004-06-04 12:05:29

Rxke
Member
From: Belgium
Registered: 2003-11-03
Posts: 3,669

Re: STOP PRESS: Scaled announce launch date

UNIMPRESSED?

Maaan, I can't believe you... Oh, wait, you mean unimpressed regarding orbital capabilities etc... OK.

I just meant: impressive how a little company slapped together this amazing PLANE... A 3-seater, better than the X-1... And for the heck of it, they built a carrier, too.

I think Rutan is a very original thinker, regarding planes, not too sure about space-stuff... But give the guy carte-blance and some $Billions... Imagine what he'd come up with ...

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#38 2004-06-04 12:45:37

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: STOP PRESS: Scaled announce launch date

Nooo still aren't getting it... manned space travel isn't ever going to be easy with any forseeable technology period, because rocket fuel doesn't offer enough push per pound, and Burt et al. aren't going to fix this. It is fundimentally harder than any Wright Brothers comparison because the physics of rocket fuel and the structure to hold it versus gravity & atmosphere dictate that no small time venture will ever pull it off alone. It doesn't matter if you have a first step or not, because the next step can't be done without unrealistic investment. No (government) bucks, no Buck Rogers

You also have this mistaken notion about "launch water ---> make rocket fuel later" thing... electrolosys of water requires alot of energy, which you don't have in orbit. Therefore, it will take time to liquify and crack that much water, in which time the fuel you produce will largely boil off. Oh and you have to add more energy to liquify the hydrogen and oxygen too to keep tanks small. You'll need radiators for that too. If you plan on liquifying boiloff gasses, that will take power and radiators as well... You just aren't going to pull this off in orbit without a pretty large fuel station.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#39 2004-06-04 18:51:26

dicktice
Member
From: Nova Scotia, Canada
Registered: 2002-11-01
Posts: 1,764

Re: STOP PRESS: Scaled announce launch date

To refuel in orbit, simply: Obtain melt-water by concentrating Solar radiation on configured ice cargo; electroyized by direct current generated by emf generated via thermopile junctions, heated on one hand by concentrated Solar radiation, and chilled on the other hand shielded from the Sun by radiating into space; resulting hydorgen and oxygen gas further chilled separately until liquified; used to refuel self propelled by boil-off gas into the respective LOX/LH2 tanks. Nothing to it, really, for a motivated team of engineers to work out.

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#40 2004-06-04 23:13:36

Mad Grad Student
Member
From: Phoenix, Arizona, North Americ
Registered: 2003-11-09
Posts: 498
Website

Re: STOP PRESS: Scaled announce launch date

Putting a "cheap reuseable first stage" on it would be the kiss of death for its supposed super ultra high simplicity of launch, because staged rockets aren't. Stage recovery, stage refurbishing, stage recertification, stage reintegration, stage testing... See "Shuttle SRB"

And yet you're such a proponent of Spacex's Falcon 1. That has a resuable first stage on it, and guess what, it is simple. The Shuttle SRBs aren't simple because of the first letter of the acronym, they are SOLID rockets. The SRBs go back to the factory, are taken apart into segments, recast with ammonium perchlorate, shipped to Florida, reassembled, and mounted on the shuttle fuel tank. All in all, the SRBs are about as resuable as a cheepo firecracker is, they're practiacally all-new by the second flight. The Falcon 1 fist stage, by contrast, is a LIQUID rocket. For liquid rocket stages all that you need to do is ship them back to the pad and refuel them, just like refilling your gas tank. Granted, that's a simplification, but it's actually not that big a pain to re-use a liquid first stage, and it's a lot easier than having to build a new one each flight.

Also, it really wouldn't cost all these billions of dollars just to make an orbital-capible vehicle. The DC-X was made in a very short time frame, on a shoestring budget compared to what most major NASA projects are allloted. Sure, the DC-X didn't get anywhere near orbit, but projects like it, and the SkunkWorks back when Kelly Johnson was involved with it, prove that you can get major things done with minimal investment, provided you have someone who knows how to get things done in charge.

I'm not a big fan of them in the X-Prize, but http://armadilloaerospace.com]Armadillo Aerospace is another good example of maximum result with minimum finances. The entire project is funded out of John Carmack's (Of Doom and Quake) pocket and so far he's only invested about $2 million. The result? They've produced hydrogen peroxide-burning engines that can easily be scaled up to produce 20,000 pounds of thrust and software that will be used on their full-size X-Prize vehicle. That doesn't sound like much (They're highest flights are up to 30 feet with thier "landers," tech demonstrators), but they have a full size vehicle ready to go, Carmack's just skittish about risking the vehicle just yet when there are so many bugs in the concept. He won't win the X-Prize, but Armadillo will get into space by the end of the year, and prove that even a group of computer programers working in their spare time on a Monster Garage budget can get to space. That will be a far bigger accomplishment than any altitude they reach.

I belive that after they're confident in their X-Prize vehicle, Armadillo plans to make a one-person-to-orbit-class VTVL rocket, a la what the end result of the DC-X project was supposed to be. Now that actually will be an accomplishment, I wish John Carmack and his team the best of luck, but I'm not holding my breath. At the pace they move it will be at least six years untill the reach orbit, but you never know...

Oh, incidentally, it's been confirmed, I'm going to see the SS1 launch! big_smile  Very, very happy about it, I'll make sure to take some crappy pictures with my crummy camera and will try to share them with all of you guys.


A mind is like a parachute- it works best when open.

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#41 2004-06-04 23:59:47

Euler
Member
From: Corvallis, OR
Registered: 2003-02-06
Posts: 922

Re: STOP PRESS: Scaled announce launch date

I belive that after they're confident in their X-Prize vehicle, Armadillo plans to make a one-person-to-orbit-class VTVL rocket, a la what the end result of the DC-X project was supposed to be.

I doubt that they will make it to orbit.  If you ignore air resistance and gravitational losses, it takes about 30 times more energy to get to LEO than it does to get to 100 km.  Note that that is not considering all of the energy that you need to carry the additional fuel that the rocket will need.  The orbital vehicle will also have a reentry speed about 7 times faster, meaning that the areodynamic stresses will be 50 times larger.

Getting to 100 km is easy.  Getting into orbit is hard.

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#42 2004-06-05 02:04:42

Rxke
Member
From: Belgium
Registered: 2003-11-03
Posts: 3,669

Re: STOP PRESS: Scaled announce launch date

Oh, incidentally, it's been confirmed, I'm going to see the SS1 launch! big_smile  Very, very happy about it, I'll make sure to take some crappy pictures with my crummy camera and will try to share them with all of you guys.

Better take yer tent with ya, then... From the RLV section of HobbySpace:

"
Alt.space Woodstock... I hear that the motels in the Mojave area were quickly booked solid for the SS1 flight and I know of at least one hangar that will be packed with people. ..."

It's going to be HUGE!  :up:

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#43 2004-06-07 07:51:00

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: STOP PRESS: Scaled announce launch date

I think you might have over-simplified the reuseable liquid stage recovery procedure a little bit... the thing comes back down in the ocean on Elon's rocket for goodness sakes... salt water, repacking the parachutes/floaters, new jettison charges, engine rechecked before firing, tank pressure testing, flight computer/electrical testing, altimeters... *rattles off list* ...You can forget about weekly flights.

And thats just to get the thing back and ready to fire, not re-mated to an upper. I think that if anyone will manage to make a orbital vehicle it will be Elon, but i've got doubts he will get much business for such a small vehicle. The Falcon-V is pretty much a pipe dream ATM... That said, I don't have much faith in him either until he actually tests his little rocket.

Thanks Euler... yeah, and for every pound of rocket fuel you carry, you need more rocket fuel to push it and so on. The little SS1 needs to be nearly a hundred times more powerful before it could think about orbit.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#44 2004-06-07 08:07:35

dicktice
Member
From: Nova Scotia, Canada
Registered: 2002-11-01
Posts: 1,764

Re: STOP PRESS: Scaled announce launch date

I read somewhere, that the discarded boosters from Soyuz launches make dandy hog-farm shelters, where they came down out on the steps in whatever 'Stan country lies in the direction launched. And they're for free.

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#45 2004-06-07 08:38:36

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: STOP PRESS: Scaled announce launch date

*Laughs*

Actually I think the US sold a stage tank for the aborted "Titan V" Barbarian rocket, to be used to launch Star Wars laser satellites, to a farmer... then needed it back for a mockup for President Regan to stand in front of on TV when proposing said laser satellites.

The DC-X and Carmack's rocket were a long, long, long way from ever being an orbital vehicle. I don't think its clear that the DC-X could keep light enough to carry a useful payload when scaled up to its big-brother the DC-I.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#46 2004-06-07 08:48:44

clark
Member
Registered: 2001-09-20
Posts: 6,362

Re: STOP PRESS: Scaled announce launch date

The DC-X et al. were being designed with a different goal though GNC, they were being designed to reduce operational costs.

We've had another decade of advances in material science, aerodynamics, computer miniturization, etc. The useful payload is people (yeah, I know, there supposedly isn't a market) who, as this board attests, are more than willing to go on a joy ride to space.

Think of it like a theme park, and the ride to space is the ultimate attraction- the biggest E-Ticket ride there is. That's how sub-orbital is going to make a buck, and it will take a handful of people. Orbital, with 10MT of payload can take quite a few people, no?

Scaling up also improves the mass ratio's given that you always have a minimum mass penalty on certain pieces of the rocket. Making it bigger isn't really going to make it worse.

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#47 2004-06-07 08:55:51

GCNRevenger
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From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: STOP PRESS: Scaled announce launch date

What i'm saying is that the DC-X itself would never ever reach orbit, and that its unclear that the real-deal big brother rocket could hit its optimistic mass estimates to be able to get there with a reasonable payload mass. In either event, the DC-I would be too expensive (>$5-7Bn) for a tourist rocket and its payload is less than current launchers, which may scare off satellite people.

The SO people are going to make bucks off tourists because SO is easy, but orbit is hard enough to make an orbital program unprofitable just for tourists.

Our materials science has advanced, but you forget that rocket fuel, the biggest contributor to vehicle mass, has not. The SSME and RL-60 already run at above 90% of the maximum theoretical efficency for LOX/LH2, the best practical fuel there is, because the hydrogen and oxygen bonds simply won't re-arrange any faster than that. Even if your structure dry mass were near zero, you would still need a big expensive rocket just to carry the fuel you need to get the fuel to get into orbit. THATS why Burt/Carmack/et al aren't going anywhere fast. Current rocket technology is reaching a plateu, where it just isn't getting any better as long as we rely on chemical rockets.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#48 2004-06-07 09:11:57

clark
Member
Registered: 2001-09-20
Posts: 6,362

Re: STOP PRESS: Scaled announce launch date

What i'm saying is that the DC-X itself would never ever reach orbit,

Well, yeah. It wasn't designed to go to orbit. It was designed to test the portions involved with launch and reentry. The follow-on's to the DC-XA program would have made orbit.

and that its unclear that the real-deal big brother rocket could hit its optimistic mass estimates to be able to get there with a reasonable payload mass.

I respectfully disagree, and I just wish they would build the damn thing to settle this between us.  big_smile

. In either event, the DC-I would be too expensive (>$5-7Bn) for a tourist rocket and its payload is less than current launchers, which may scare off satellite people.

Even at 5-7 billion, it costs less than what it does to develop a new commercial jet. And I think what you might be missing here is that the DC-X was being designed to lower operating costs. It was being designed to be more like a jet airliner, and less like a rocket. It can have a lower payload mass because you can turn the rocket around every week (which was how they said the Shuttle would make money!). Then launch costs become a factor based on fuel costs- not construction costs.

Everytime we fly, the prices will fluctuate a little- why? Not because the airplane needs an extra bolt, or a new engine. No, it costs more or less based on the price of fuel. That is the driver. The cost of the ship is pretty much taken out of the equation because it can depreciate and you can use it a bunch of times.

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#49 2004-06-07 09:19:13

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: STOP PRESS: Scaled announce launch date

Ah but there is a market for a commertial jet liner, a market consisting of dozens of copies of aircraft (more for your devel. money) that each carry hundreds of people willing to pay hundreds of dollars and fly hundreds of times per year.

There is no market for such an RLV today, even if its launch overhead costs were essentially zero, in order to repay these billions of dollars needed to build it. A few dozen space tourists a year willing to cough up $10M once in their lives isn't going to bring in enough money to make it fly. Plus, there aren't enough satellites to be launched, which today cost several times what their launch vehicle does, to bring in the cash either even if the DC-I monopolized the launch market entirely.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#50 2004-06-07 09:20:38

Bill White
Member
Registered: 2001-09-09
Posts: 2,114

Re: STOP PRESS: Scaled announce launch date

Everytime we fly, the prices will fluctuate a little- why? Not because the airplane needs an extra bolt, or a new engine. No, it costs more or less based on the price of fuel. That is the driver. The cost of the ship is pretty much taken out of the equation because it can depreciate and you can use it a bunch of times.

This can be explored with a simple exercise.

Ascertain the acquisition cost of your alt-space RLV.

DH-1, DX-1, JP Aerospace's dirigible to LEO, space elevator, hypersonic skyhook, matter/energy transporter, whatever, the technology doesn't matter. How much does ONE cost?

Estimate a reasonable useful service life. Amortize the acquisition cost over that service life with a reasonable interest rate.

Then estimate a reasonable payload delivery capacity per week or month. X kilos per month.

Then calculate your cost per pound for capital investment.

IMHO, these alt-space thingees are going to have one heck of a time beating the Ukrainians on price, even if sufficient demand existed to fly often.

So, who will invest billions to build one on spec (as a speculative investment)?

= = =

$6 billion in R&D, right? To recoup over 10 years at 9% interest that will require how much per month in revenue?

At 9% interest isn't the monthly interest $45 million?

Absent government subsidy, you need to generate $45 million per month in paying revenue just to cover the interest, not even thinking about principal, fuel, salaries and insurance.

At $1000 per pound you need to lift 45,000 pounds just to pay the interest on the R&D. At $100 per pound you need to lift 450,000 pounds per month just to pay the interest.

= = =

Doesn't PlanBush cancel most investment in lower cost Earth to LEO, to focus instead on EELV CEV?

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