While that might be true for the Western world, it's not necessarily true for Russia: Russian spaceship with nuclear engine developing

Ba-da Bingo, ba-da boom.

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If I set the budget, we'd have Ares and more. Unfortunately, I don't set the budget, and Ares is just too expensive and too far out for us to accomplish our goals within the budget we were given.

If we halt the ISS, all versions of Ares, and transport Orion and Altair aboard DIRECTv3's Jupiter family of Shuttle-Derived Launch Vehicles, we just might make it back to the Moon by 2020.

Well those breakthroughs are the very thing Reaction Engines may have acheived. Also isn't the cost per kilo of payload a major factor in launcher choice? Theoretically an SSTO could be an attractive option for many applications. It could, based on the figures Antice quoted, even put a crew capsule similiar to the Dragon into orbit, especially if that capsule didn't need its own re-entry capability.

Throwing away the entire jet airliner after every, say, 2000 miles, how much do you think airline travel would cost?


Bob Clark

The proposal was to transform the X-33 into a reusable, orbital vehicle using NK-33 engines. The NK-33 was a Russian 1960's era engine so I thought they would have to be taken out of mothballs for the purpose. But I recently found that Aerojet is working with the NK-33 engines to be used on Orbital Sciences’ Taurus 2 launcher:

08/31/09 10:15 AM ET
Aerojet Looking to Restart Production of NK-33 Engine.
By Amy Klamper
http://www.spacenews.com/launch/aero...33-engine.html

August 19, 2009
Russian Mail-Order Ride.
http://blogs.airspacemag.com/daily-p...il-order-ride/

Aerojet has already purchased several of the engines, and is debating whether to start it's own production lines or to use Russian production for future purchases of the engine. Then the Air Force or NASA could use these to make a reusable, single-stage-to-orbit vehicle and near term, at least for a prototype vehicle. There was some debate on the Augustine commission if NASA and the U.S. should use Russian engines for a significant portion of their launches, but this complaint might be ameliorated in regards to the NK-33 if production lines were started in the U.S.
A question would be of the payload it could carry. The preliminary calculations I made suggested it might just make orbit, so likely it would have low payload capability. Some possibilities to increase the payload might be to densify the kerosene propellant by subcooling to near LOX temperatures or to use more energetic hydrocarbon propellants. The densification would allow it carry more propellant. Some possible energetic hydrocarbon propellants are suggested here:

Alternate Propellants for SSTO Launchers.
Dr. Bruce Dunn
http://www.dunnspace.com/alternate_ssto_propellants.htm

Another possible method to increase payload would to use a version of the NK-33 with an aerospike nozzle. This would allow it to have higher Isp at sea level.

It should also be possible to use the hydrocarbon fueled X-33 as a reusable first stage booster. The Air Force is investigating such boosters as a means of cutting costs to space. Since the reconfigured X-33 would be able to reach orbit at 21,700 kg dry mass, it could be able to lift in the range of a few thousand kg's payload as the first stage of two stage-to-orbit-system.


Bob Clark

There is legitimate doubt about weither a SSTO like this is even capable of having a positive payload fraction. it seems from the literature i have perused that payload fraction at best can reach 2% of the vehicle mass. most calculations show it to be someplace closer to 1% or even negative. compare this to something Like Falcon 9 that has a payload fraction of approx 3,%.
The skylon has a theoretical payload fraction of a whooping 4,3%
Launching straight up on a tail of fire with internal oxidizer is horribly inefficient when it comes to weight to payload capability. this is why rockets stage in the first place. by dumping large parts of the vehicle during ascent you save on the amount of mass you have to bring into orbit. The X33 was a very marginal design to begin with. and the problems it had during development did not exactly help.

pure rocket powered SSTO vehicles are not a particular viable means of transport into orbit unless you go nuclear. the higher ISP of nuclear thermal engines can in theory help improve the payload fraction to something more edible. however. this is not politically sane for the foreseeable future.

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Aerojet claims their version of the NK-33 is "fully reusable":

Space Lift Propulsion.
http://www.aerojet.com/capabilities/spacelift.php

Anyone have any idea what they mean by that?

Bob Clark

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Do you a reference for those studies that say it's not possible? That may have been the case with only steel and aluminum construction materials. But the competing proposals for the X-33 suborbital demonstrator and for their full scale reusable orbital versions all used carbon composites for most of the structural mass including the propellant tanks, which amounts to a large weight saving, perhaps 1/3 to 1/2 of the structural mass.


Bob Clark

Which ended up weighing the same as aluminum tanks

Smarter people than you have said it

I have to admit i do not have the links to these studies on my current rig. it's been a while since i spendt all that much time researching the x-33's feasibility. I'm willing to cede the point and assume a theoretical payload rate of 2% it's what i use when i compare options anyhow.
Composite materials most likely do make for a positive payload ratio. however. the efficiency is still way below what single use rockets can achieve.
propellant tanks in composite materials have not been proven feasible either. not for cryogenic fuels at least. switching over to RP1 makes the composite tanks lots more viable. as long as you use a pump fed system. however. your fuel mass has not decreased. it indeed have to increase due to RP-1's lower ISP in the range of 270 to 360 seconds, while hydrogen fueled engines achieve 370-465 seconds. i havent done the math here. but for the tanks at least that difference may eat up all the savings if not even more.

If SSTO is to be feasible one needs to think untraditionally. forget how standard rocketry does things and try something new.
Ramjets might be useful. but LACE technology has it beat hands down for SSTO use. something new might show up that beats LACE tech too. but i'm not holding my breath.

using a tension supported structural system solves a lot of the insulation issues you get with a composite braced structure.
Carbon composites dont take heat all that well. so you need a thick shuttle type TPS or maybe even thicker in order for it to maintain structural integrity troughout flight. by using a tension system you can suspend your tanks inside a hollow fuselage and keep the 2 parts from touching. this reduces the amount of insulation needed. the gap helps keep the hot outer shell away from the composite structure within. it also allows venting of residual cryogenic gases into the gap to help actively cool the outer skin during the hottest parts of re-entry. in the end you only need to insulate the points where your fuselage attaches to your structural members. thus saving quite a lot of weight. as a bonus. your tanks are no longer a part of the structure of the launcher, and now only need to be sized for holding the fuel. that means thinner tank walls and thus. lighter tanks as well.

In the end. it's not one thing that will make SSTO's a feasible option. it is a multitude of new ideas and new ways of thinking that will get it done.

This is the kind of thinking that gives other proposed SSTO's their edge on feasibility compared to the X-33/venturestar. but hey. if you used any of these methods it would not resemble the X-33 in the least anymore.

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Smarter people than any of us have also said that with recent lightweight materials it is now possible.


Bob Clark

None of your proposals are feasible. They ignore physics.

The "recent"ightweight materials are still not viable.

I concur. "Carbon fiber" isn't a miracle cure.

__________________
If I set the budget, we'd have Ares and more. Unfortunately, I don't set the budget, and Ares is just too expensive and too far out for us to accomplish our goals within the budget we were given.

If we halt the ISS, all versions of Ares, and transport Orion and Altair aboard DIRECTv3's Jupiter family of Shuttle-Derived Launch Vehicles, we just might make it back to the Moon by 2020.

They don't have to be a miracle cure, just good enough.
As an example nearly twenty years ago GM introduced a concept car with body frame composed of carbon composites that achieved 100 mpg highway mileage. The body frame was constructed by, you guessed it, Scaled Composites.
This was not a hybrid car, but a standard sized four-passenger car with a internal combustion, gasoline engine:

General Motors Ultralite.
http://en.wikipedia.org/wiki/General_Motors_Ultralite

G.M. to Show a High-Mileage Experimental Car.
By DORON P. LEVIN,
Published: Monday, December 30, 1991
"The latest experimental vehicle from the General Motors Corporation, a high-mileage four-passenger car with a body made of carbon fiber, promises to enliven the debate over fuel-efficiency legislation.
"At the North American International Auto Show in Detroit next week, G.M. will show its Ultralite, which the company says can produce 100-mile-a-gallon fuel efficiency at 50-mile-an-hour highway speeds.
"That efficiency is possible, G.M. said, because the car weighs only 1,400 pounds. (A Chevrolet Corsica, which is approximately the same size as the Ultralite, weighs about twice as much.) Scaled Composites Inc. of Mojave, Calif., built the Ultralite body for G.M."
http://www.nytimes.com/1991/12/30/bu...ental-car.html

The key to the high mileage was that since the body frame and shell was lighter, you could use a smaller engine and get the same speed and acceleration of a normal weight car. The lighter engine also contributed in a synergistic effect of getting comparable performance at a lighter weight.
This is exactly what happens when using composites for most of the structural weight for a rocket. The lighter weight means you can use a lighter engine which decreases the weight even further, meaning you reduce the fuel load further again.
This was in 1991 and as the NY Times article mentions the carbon composites used in the cars body frame were quite a bit more expensive than steel. But the price of carbon composites has been dropping. One company claims they will soon introduce a process that can produce carbon composites at low price:

The affordable, 100mpg, carbon-composite passenger car.
By Loz Blain
11:12 July 17, 2008 PDT
http://www.gizmag.com/the-affordable...nger-car/9643/

Undoubtedly the price for carbon composites will drop significantly at some point. At that time reusable SSTO's will be just as inexpensive to produce as standard multi-stage expendables.


Bob Clark

Dave Akin a professor of aerospace engineering has come up with some "Laws of Spacecraft Design." Most have a humorous bent but the number 1 "law" is quite telling:

"1. Engineering is done with numbers. Analysis without numbers is only an opinion."

Akin apparently does think a hydrogen/LOX single-stage-to-orbit vehicle is possible based on the calculations he presents in one of his courses:

ENAE 483/788D - Principles of Space Systems Design
http://spacecraft.ssl.umd.edu/academ...F09.index.html

The specific lecture is on estimating the masses of components of a rocket in which he calculates the dimensions of a viable hydrogen/LOX SSTO:

Mass Estimating Relations.
• Review of iterative design approach
• Mass Estimating Relations (MERs)
• Sample vehicle design analysis
http://spacecraft.ssl.umd.edu/academ...F09L13.MER.pdf

This is for a single-stage-to-orbit but *not* reusable vehicle. Keep in mind though the mass estimations he uses are derived from standard aluminum and steel construction, based on the references he gives at the end.
Then since carbon composite construction could save 1/3 to 1/2 off the structural mass, there would be well enough margin for landing gear and thermal protections systems, which mass far less than a third of the structural mass.

Bob Clark

Synergistic effects aside. the X-33 design is still unviable as a disposable rocket replacer. It does not help how much of a diet you try to put it on. it's not made out of steel. it's made out of honeycombed aluminium and other already light materials. secondly. large parts of the structural mass cannot be made out of carbon composites. the temperature regime it is exposed to is too extreme.
The design in flawed. it's better to drop it in favor of better ideas.

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It's not good enough.

And I own a chrome-moly steel, two-wheeled vehicle that gets the energy equivalent of 600+ mpg. With an engine that evolved a few billion years ago. It's called a bicycle.

Anecdotes are not evidence, RGClark. Volkswagon tested a 214 mpg vehicle thirty years ago. That means little.

As does the fact that there's a car on the market right now that gets 300 mpg.

This, too, means nothing with respect to the viability of a SSTO craft.

The price of carbon composites has absolutely nothing to do with the engineering viability of a SSTO craft, Robert.

What does matter is that multiple stages are more efficient, to a point, than a single stage. The limit is defined by the fact that one has to have separate nozzles and control systems for each stage. Even so, Apollo would have been more efficient with seven stages, but it would have been much more costly, and significantly less reliable. They absoultely needed three stages, however, so they opted for three.

__________________
If I set the budget, we'd have Ares and more. Unfortunately, I don't set the budget, and Ares is just too expensive and too far out for us to accomplish our goals within the budget we were given.

If we halt the ISS, all versions of Ares, and transport Orion and Altair aboard DIRECTv3's Jupiter family of Shuttle-Derived Launch Vehicles, we just might make it back to the Moon by 2020.

That's a little like saying the Wright brothers "Wright Flyer" is not the best design for an airplane. My point is the X-33 being 85% built can give us a *prototype* single stage to orbit reusable vehicle NOW with the modifications to dense hydrocarbon fuels and engines.
The same would also be true for the other proposed half-scale suborbital demonstrators when likewise reconfigured to dense hydrocarbon fuels and engines. That is, they would also become full orbital, single-stage-to-orbit reusable vehicles, not just suborbital demonstrators. I would be fully in favor of the development of those being initiated. However, the cost of these starting at the beginning likely would be comparable to that of the X-33, in the range of $1 billion.
However, in the case of the X-33 it is already mostly built and paid for.


Bob Clark

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I'm aware that *hybrid* vehicles can get good "miles per gallon" (with a debatable definition of "mileage" for a partly electric vehicle). My point was the fuel load can be markedly reduced for a standard gasoline engine powered regular sized vehicle using carbon composite construction. Note the Aptera is only half-sized and even then it's able to achieve its long travel times on only one charge specifically because it also uses carbon composite construction!
If you only looked at steel constructed, standard-sized cars using the standard gasoline engine, you would say it is impossible to get 100 mpg. But because of the weight savings using carbon composites that quite importantly also drives very light engines this becomes possible.
The severe fuel savings by switching to all composite construction while using the same kind of engines is the entire point of the matter.
You do know why Scaled Composites used all composite construction for their record long distance and X-prize winning craft don't you?


Bob Clark

1. the wright brothers flight was more akin to multi stage rockets than any ssto concept.

2. the X-33/venturestar is unviable because it depended on composite structures that are non viable. the oddly shaped tanks in the X-33 are structural. that means they have to carry the vertical loads on the vehicle. Carbon composites are not able to maintain strength when cryogenically frozen. ALL X-33 performance numbers were derived using LH2-LOX as fuel. swapping fuel to RP1 or similar dense fuel means that you have to add more fuel mass to achieve the same D-V numbers.
this means you vehicle shrinks in volume. but increases in mass.
Changing fuel is therefore non-viable for the current x-33 configuration where tanks and suports are dimensioned for the large volume low density LH2.
going with aluminium tanks means that you add much weight. remember. the X33 tanks are structural. they need to carry the mass of the vehicle during launch.

3. The X-33 is just an oddly shaped rocket. it would have been much more efficient to have tried to make it in the shape of a rocket as well. especially since that would have removed a lot of the extra structural mass added to achieve the odd shape. the odd shape had only one function. and that was to add to the cross range capability of the vehicle. trading cross range for payload in such a case is the most sane thing to do.

In short. the X-33 failed due to multiple factors. not just the mess up with the non workable composite tanks. but also trough having features that did not really add to the crafts utility in any meaningful matter.
Once these shortcomings started to make themselves felt they cancelled it.
Starting over with a new design that removes these basic flaws is the most sane thing to do in such a case. the only thing worth retaining from the x-33 is the aerospike nozzle. but with the advent on expansion/deflection nozzle technology that too is becoming less likely to be useful.

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Take the Saturn V. Look at the differences between the size of the LOX and RP-1 tanks of the first stage and then look at the tank sizes of the LH2 and LOX tanks of the second stage.

Neither stage could support the other fuel type. The tanks and hence the basic structure of of the X-33 designed around the the volumetric ratio of LH2 and LOX.

Changing to RP-1 means RP-1 would have to go into the original LOX tanks and LOX in to the original LH2 tanks to even get near the proper ratio. Now, the CG of the vehicle is all messed up.

[QUOTE=RGClark;1626232

Akin apparently does think a hydrogen/LOX single-stage-to-orbit vehicle is possible based on the calculations he presents in one of his courses:

[/QUOTE]

That is meaningless. The issue is sufficient payload to make it viable. That is the problem.

You keep spamming these boards with your non viable proposals that are based on only internet links and unproven technology.

Next time, do all the numbers yourself starting from scratch.

You're ignoring the point. Akin shows a SSTO, but not reusable, hydrogen/LOX vehicle with 5,000 kg payload IS possible with standard aluminum and steel construction materials. The point is an all composite construction would shave 1/3 to 1/2 off the structural mass which then could go to landing gear and thermal protection so that it now becomes reusable. Note this does NOT require changing the fuel or engines.
Why don't you read what he says first, then comment on it?


Bob Clark

Well, quite key to my proposal was the several methods I suggested for getting the propellant mass/tank mass ratio to be comparable to that of normal cylindrical shaped tanks. If you can do just that you wouldn't need to change the fuel or the engines to get the X-33 to reach its original Mach 15 suborbital performance goals. And moreover the full-scale VentureStar would now have an increased payload capacity to orbit because of the significantly reduced dry mass that could go to further payload.
I agree with you the other competing RLV proposals could have accomplished this more easily, mainly because they wouldn't have the problem with the overweight tanks. But starting now from scratch on these would add likely a billion dollars development cost and at least 5 to 6 years development time.
The X-33 tank modifications would be trivial and low cost to accomplish and could be done within a year.


Bob Clark

No Bob. that was my point. the redesign of the tanks is not trivial. they are a part of the load carrying structure.
Redesigning it for RP1 would mean redoing the shape of the craft entirely. also the craft would grow in weight even tho it needs less volume due to the increase in propellant mass needed to get into orbit with RP1. all of these changes would alter the empty Center of gravity as well. and this factor is critical to help maintain the proper angle of attack during re-entry. to far forward and the craft will tend to dive in nose first. too far back and the craft will be unable to straighten it's glide path into a forward slope during the latter parts of the entry phase. both of these issues will kill the vehicle if not sorted properly. a blanc sheet is sometimes cheaper. and in this case I am of the firm opinion that the sunk cost fallacy holds true. the X-33 cost is well and truly sunk without much benefit to show for it.
The best option is to take the lessons learned about what does not work, and start anew.

When it comes to SSTO viability in general there are several factors that counts. one is the trade between cargo and enhanced utility. you can trade one for the other. but you cannot have the sum be less than the sum of the cargo and utility of a single use staged rocket.

Let's take the case of a single stage to orbit disposable rocket. it's cargo capability is less than the cargo capability of a similarly massed staged rocket. it's utility bonus is that it's a simpler cheaper design. however. the lesser cost of the rocket does not outweigh the higher performance of the staged vehicle. the staged rocket wins the cost per kg contest and is therefore the prefered option.

The shuttle has the same problem. it's reusablity is marginal at best since it is unable to return to it's starting position by itself. it's also a lot more complex and costly vehicle than the staged rocket. in this case the staged rocket wins again.

then we have the venturestar. at first glance it looks more promising than the shuttle. however. if you analyze the design features a bit you will soon notice that it has most of the shuttles drawbacks. it's a maintenance heavy craft that while reusable is also even more complex than the shuttle. and with even less cargo capability than the shuttle as a final insult to injury. in hindsight I'd say that the venturestar has features that are actually wasted. stuff like the lifting body shape that is not actually adding any important capability. (crossrange landing capability is not a big utility enhancer with out the ability to land at your launch site)

my last excample is the only concept currently in the works i think have a glimmer of hope when it comes to beating staged rockets. It's the skylon vehicle.
They are trying to bypass the cargo penalty partly trough the use of novel hybrid air/rocket engines as well as utilizing a lifting body shape to enhance the ascent profile into one where the needed engine power is reduced by a sufficient margin to allow a substantial mass saving in the overall design. a novel structure allows a wider use of those composites you are so fond of as well. while at the same time allowing for a thinner stiff outer shell that can take the heat without impacting the tanks and structures within. these 3 major mass savers actually bring the theoretical mass fraction up to a level where it not only competes with, but exceeds staged rockets.
as for utility. well it's a reusable HOTOL. it has the same utility level as that of an airliner. you cant get much better than that.
This is a vehicle that can potentially drop launch costs to the level where even medium rich peeps can get into space. as opposed to the filthy rich that are the only ones able to do it today.



ETA: A VTOL has a higher mass penalty than a HOTOL due to the need to use fuel during the landing phase. there are also more esoteric concepts out there that could have been used to make a VTOL SSTO. but the common problem between them all is that the extra complexity really comes at a cargo capability cost. this acts as a price multiplier for the cargo launched and throws most of these firmly onto the pile of non viable cost wise.

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Dude, I'm saying you don't have to change to RP-1.
With the change in the design of the tanks I was suggesting they would still be integral, i.e, load bearing, but would be lightweight to be comparable in weight to normal cylindrical tanks. The X-33 would still be suborbital now, but it could meet the original performance goals it was expected to before development of the full orbital VentureStar.


Bob Clark

[QUOTE=RGClark;1626495]You're ignoring the point. Akin shows a SSTO, but not reusable, hydrogen/LOX vehicle with 5,000 kg payload IS possible with standard aluminum and steel construction materials. The point is an all composite construction would shave 1/3 to 1/2 off the structural mass which then could go to landing gear and thermal protection so that it now becomes reusable. Note this does NOT require changing the fuel or engines.
Why don't you read what he says first, then comment on it?
QUOTE]

No, he only showed numbers. Akin has not built any launch vehicles.

Cryogenic composite tanks are not viable. they have too many issues.
cylindrical tanks can not support the shape of the x-33. that is 2 mutually exclusive criteria. making an entirely new vehicle with cylindrical tanks will in this case actually be a cheaper option. any change in form shape or material of the tanks will alter the crafts center of gravity profile. this negates the lifting body design entirely. lifting bodies must be balanced right or else they fail.
the last nail in the coffin for the x-33 is that it like most other failed concepts adds complexity while reducing payload capability. not only is your vehicle more costly. but it lifts less cargo than a conventional rocket. with re usability depending on major work effort and unique infrastructure you get a dinosaur that costs more than a conventional launcher per unit launched.

Let me recap the main point.
Any Launch system has to compete on the same marketplace. and the final apples to apples comparison is the cost per kg on orbit payload. in essence. you have to beat the falcon 9 on cost. it has to be cheaper than about 4800$ per kg to LEO. (2009 dollars)

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[QUOTE=RGClark;1626389]I'm aware that *hybrid* vehicles...[quote]

VW's 214 mpg car was an internal combustion engine. It was not a hybrid.

It's right-sized. They designed it to be precisely the size it is.

Thank you for helping make my point: You're wrongly attempting to translate what works for road vehicles into what will work for Earth to LEO spacelift. Again, carbon-fiber isn't a miracle cure. There are places where it's appropriate, but the Space Shuttle's External Tank, for example, wasn't one of them. Carbon fiber was considered, and discarded. They opted for AL 2195, an aluminum/lithium alloy, instead, for the Super Lightweight Tank which has been flown since 1998, and is required for the Shuttle to reach the ISS.

And thanks for helping to make another point: You're errantly believe we're opposed to composites. We're not.

We're opposed to SSTOs. Our opposition has absolutely nothing to do with the materials out of which its structure is made. Rather, it has to do with the fact that any SSTO hauls additional mass to LEO that doesn't need to be there, and in so doing, lowers it's available payload.

We're not saying it's impossible.

We're saying it's impractical.

We're in the spacelift business, not the James Bond or the sexy jet business. The $/kg to LEO cost may not matter in your world, Robert, but it matters in the real world. SSTOs are prohibitively inefficient in terms of moving payload from Earth to LEO.

__________________
If I set the budget, we'd have Ares and more. Unfortunately, I don't set the budget, and Ares is just too expensive and too far out for us to accomplish our goals within the budget we were given.

If we halt the ISS, all versions of Ares, and transport Orion and Altair aboard DIRECTv3's Jupiter family of Shuttle-Derived Launch Vehicles, we just might make it back to the Moon by 2020.

Empty Weights:

External Tank (SLWT): 58,500 lb
SRBs: 200,000 lb
Total: 258,500 lb

Weights with fuel:

ET: 1,680,000 lb
SRBs: 1,300,000 lb
Total: 2,980,000 lb

The weight fraction of the the Stage I and II propellant containers is 258,500 / 2,980,000, or just 8.67%.

Meanwhile, since the entire SSTS weighs 4,400,000 lb at liftoff, the payload to LEO of the Space Shuttle is 53,600 lb, with a weight fraction of just 1.2%.

To be fair, a good 120,000 lb of the orbiter could be shaved if it were merely a cargo container instead of a reentry vehicle, which would similarly increase the payload to 173,600 and the weight fraction to 3.9%.

In case you didn't catch my drift, the structure is but a pittance compared to the mass of the fuel required to lift the payload to orbit, and it's already as light as is economically feasible.

SSTO doesn't improve those numbers, it makes them much worse because you're now hauling additional structural material to LEO that commensurately reduces your available payload. It may be technically possible, but SSTOs are not economically feasible.

The entire approach is wrong, just as the idea of using a Space Shuttle was wrong, as it wasted sixty tons of payload every mission. It's per-mass cost to LEO is among the highest of all LEO spacelift systems in existance today.

Your SSTO cost per payload mass will be higher.

__________________
If I set the budget, we'd have Ares and more. Unfortunately, I don't set the budget, and Ares is just too expensive and too far out for us to accomplish our goals within the budget we were given.

If we halt the ISS, all versions of Ares, and transport Orion and Altair aboard DIRECTv3's Jupiter family of Shuttle-Derived Launch Vehicles, we just might make it back to the Moon by 2020.