A cheap and easy way to space.

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csmyth3025

Guest
neutrino78x":3hc4pjm2 said:
So could we make an X-33 type rocketplane that launched horizontally, like an airplane? Like I said, like that Lynx rocketplane, except using hydrogen and oxygen instead of hydrocarbon (for environmentally clean exhaust). Still can't believe they canceled the X-33, it was a great idea.

--Brian

The X-33 was a sub-scale demonstration vehicle for a (proposed) larger single-stage-to-orbit spacecraft called the VentureStar. For the reasons I've mentioned in my previous posts, single-stage-to-orbit spacecraft are not feasible with the technology we have today. In the future it may be possible to air-launch orbital vehicles similar to the VentureStar, but we don't have that sort of air-launch capability yet. The proposed VentureStar would weigh in at 2,200,000 lbs, which is 5 times the external payload of the largest cargo aircraft in existence (the Russian AN-225).

Chris
 
E

EarthlingX

Guest
Here is something about Antonov that you probably didn't know, well, at least i didn't, but is related :
from http://www.antonov.com/
Aerial launch
Nowadays Antonov Aeronautical Scientific Technical Complex jointly with Russian enterprises of aeronautical branch develops the project of a launch of artificial satellites with the help of aeronautical systems. The project is called “Aerial Launch”. Launch of a carrier rocket (CR) from an airplane allows:

* to reduce the cost of space apparatus (SA) putting in the orbit in several times;
* to provide the wide range of SA orbits’ slope;
* to save time for preparation to the re-launch;
* to reduce injurious effect on ecology
* to increase a mass of the load launching to the orbit.
 
C

csmyth3025

Guest
The AN-225 and other similar heavy-lift cargo aircraft demonstrate the technical feasibility of designing an air launch platform that can achieve altitudes high enough and carry payloads heavy enough to put practical air-launch-to-orbit systems within reach. An air launch platform designed specifically for sub-orbital flights already exists in the form of the "White Knight Two" by Scaled Composites. Future iterations of this type of aircraft may go a long way towards providing "a cheap and easy way to space" for crew transport and relatively small payloads to LEO. In this regard I use the terms "cheap" and "easy" only as compared to the methods we now use.

Most of us have a hard time envisioning the future. We tend to think in terms of the technology we now have and then we sort of mentally add to that the incremental improvements we think might be made over the coming years. One unforeseen breakthrough - such as the development of the transistor - can change the technological landscape entirely. I think such a breakthrough will be needed before we have a truly cheap and easy way to space.

Chris
 
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halman

Guest
js117":2ljgqf98 said:
This launch rail system was used in and old classic Science Fiction Movie " When Worlds Collide " made in 1951.
If you have seen the movie is this what you are talking about.

I don't believe so. If I remember that movie correctly, the spaceship provided the driving power, the rail was simply a track that it rode upon.

What I envision is a cradle which rides on wheels. This cradle supports the carrier wing, which would have the orbiter on its back. The cradle is powered externally, either via a magnetic 'linear motor', or by a rocket powered sled which pushes the cradle. Or, a combination thereof, to overcome the difficulty and danger of getting a large mass rolling using magnetic fields alone. This system should be capable of accelerating the launch stack to take off velocity without the carrier wing engines being used at all.

Of course, they would be used, to insure that the engines are performing properly, but their thrust would be incidental to the acceleration to take off speed. Conversely, the launch rail provides a means of slowing the stack down in the case of an abort, using magnetic braking, resistance, and cable arrest systems.
 
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halman

Guest
scottb50":2527nb6z said:
js117":2527nb6z said:
by halman


In my visualization, a launch rail is indispensable, because the stack will weigh in at around 2,500,000 pounds. An undercarriage that could support that amount of weight is going to weigh hundreds of thousands of pounds, which is totally unnecessary. A cradle, which rolls along the launch track, can support the weight of the two vehicles, and act as the driven element in the catapult. This way, the stack is removed somewhat from the powerful magnetic fields of a railgun. The term 'catapult' implies rapid acceleration, which is misleading, I think. What is desired is to be able to accelerate the stack smoothly to a speed where the carrier wing has several tons of positive lift, so that it will fly out of the cradle, which I estimate will be at about 300-350 miles per hour. This insures positive control once the stack is airborne, and avoids the fuel penalty involved in the carrier wing's engines being solely responsible for accelerating the stack from a standing start.

Once you are airborne you are in pretty much the same place you would be on the ground, it's still going to require rockets to get to orbit, that could probably pretty much get you there directly a lot easier, and much cheaper. Escape provisions from the pad, or rail to orbit are another requirement.

Scottb50,

If what you say were true, rockets would not take off straight up, they would take off pointing about 30 degrees above the horizon. If what you say were true, the space shuttle would not have to throttle the main engines back to 60 percent immediately after lift off. If what you say were true, the space shuttle would not use 3/4's of its propellant to reach 100,00 feet and 1 mile per second.

As I explained in my previous post, escape from the rail is not necessary, because the rail is capable of bringing the stack to a stop, even from take off speed. If you want to insist that any launch system be completely safe, we will never leave Earth. The energy involved is simply too great. I believe that my concept provides greater safety than any existing launch methods, by allowing the orbiter to separate and return to the launch site at any point during the climb to launch altitude.
 
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halman

Guest
csmyth3025":3qdodw1l said:
The AN-225 and other similar heavy-lift cargo aircraft demonstrate the technical feasibility of designing an air launch platform that can achieve altitudes high enough and carry payloads heavy enough to put practical air-launch-to-orbit systems within reach. An air launch platform designed specifically for sub-orbital flights already exists in the form of the "White Knight Two" by Scaled Composites. Future iterations of this type of aircraft may go a long way towards providing "a cheap and easy way to space" for crew transport and relatively small payloads to LEO. In this regard I use the terms "cheap" and "easy" only as compared to the methods we now use.

Most of us have a hard time envisioning the future. We tend to think in terms of the technology we now have and then we sort of mentally add to that the incremental improvements we think might be made over the coming years. One unforeseen breakthrough - such as the development of the transistor - can change the technological landscape entirely. I think such a breakthrough will be needed before we have a truly cheap and easy way to space.

Chris

No one really knows what launch costs would be if we were to use a mass-produced step rocket launched with great regularity. The Russians have probably come closer to defining those costs than anyone else, but they have never been forthcoming about what those costs truly are. Irregardless, I am convinced that my concept has the potential of reducing the cost of putting a human being in orbit to the level of a few thousand dollars, if it is used on a frequent basis. The only method that could be cheaper would be a space elevator, which is simply beyond our current and foreseeable abilities.

I believe that a space elevator will someday be built, as long as the amount of commerce in space warrants the expense. To begin creating that commerce is my goal, to make affordable the transport of the critical component in any research-and-development enterprise, the human being who must learn to think in terms of zero gravity. As long as our minds are chained to conditions on Earth, we will never utilize the full potential of space.
 
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csmyth3025

Guest
When I think about it, the technologies necessary for a completly reusable launch-to-orbit system exist presently or are in avanced stages of design. We have the proven technology to build a railed vehicle system capable of attaining speeds of 350 mph. Such as system could be adapted to serve as a rail launch undercarriage.

I understand that Scaled Composites and Virgin Galactic are in the design phase for a SpaceShip 3 iteration of the SpaceShip 2 air launch platform. I can see no reason, other than funding, that would preclude a fourth or fifth generation aircraft of this design being built that would have the heavy-lift payload capability of 1 million lbs or more. This maximum payload might become more attainable if air refueling of the mother ship is empoyed. Likewise, airborne fueling of the launch craft (if feasible) might also be used.

The 100% reuseable proposed VentureStar space plane (the full-size production version of the x-33) has been listed in Wikipedia as weighing 2,200,000 lbs with a payload capacity of 45,000 lbs. These figures are for a ground-launched VentureStar, though. I suspect that an air launch version of this craft would weigh considerably less - particularly if it's designed primarily for crew transport and, thus, smaller payloads.

If these elements are put together, a fully reuseable launch-to-orbit system could be constructed in the foreseeable future.

Chris
 
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halman

Guest
If we really wanted it, this system could be operational in 5 years. It will cost a bit more, perhaps, than if we take 7 or 8 years, but not substantially so. The single greatest challenge is building the carrier wing. I advocate one which could lift at least 1 million pounds, and would prefer to see one with a 1.5 million pound payload ability, simply because I think that demand for this system would ramp up rather quickly, once it was online.

Human access to space is the single greatest thing holding back development in space. Being able to carry 10 people in a single launch would at least triple the current capacity, and still more than double what the Orion would carry.
 
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csmyth3025

Guest
Several questions:

Does anyone know what the payload capacity of the White Knight Two is? Is the design of White Kight Three already on the drawing boards? If so, does anyone know what its payload capacity would be?

The Soyuz TMA (the currently used Russian crew transort vehicle) weighs about 16,000 lb according to the article about it in Wikipedia. I guessing that this is dry weight (the vehicle without propellant and payload). Does anyone know what the mass of the fully loaded Soyuz TMA is? Also, Does anyone know what the mass of a booster rocket capable of taking the Soyuz TMA to LEO from 50,000 ft would be? Do any such rockets now exist "off the shelf"?

I ask these questions to determine if there are currently available components the could possibly be assembled as a first-generation demonstration of air-launch-to-orbit technology.

Chris
 
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js117

Guest
halman wrote

"I don't believe so. If I remember that movie correctly, the spaceship provided the driving power, the rail was simply a track that it rode upon."

I looked at the move again and there are rockets below the sled firing before the main starts
Theses are like jeto rockets that the Blue Angles us get thre C-130 up in the air.
 
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csmyth3025

Guest
rockett":cbta2yvl said:
Something like this could be "game changer":

Air Force to Test New Hypersonic Aircraft
http://www.space.com/news/usaf-hypersonic-research-sn-100309.html

Only spent "$250 million" too (sigh) :(

The difficulty in using scramjets to achieve orbital speeds is summed up in the Wikipedia article on scramjets as follows:

"...Scramjets might be able to accelerate from approximately Mach 5-7 to around somewhere between half of orbital velocity and orbital velocity (X-30 research suggested that Mach 17 might be the limit compared to an orbital speed of Mach 25, and other studies put the upper speed limit for a pure scramjet engine between Mach 10 and 25, depending on the assumptions made). Generally, another propulsion system (very typically rocket is proposed) is expected to be needed for the final acceleration into orbit..."

The SR-71 Blackbird has a reported top speed of about Mach 3.4 (officially listed as Mach 3.2). It's a very sophisticated (and expensive) aircraft. Its not designed for carrying significant payloads (only two crew members and about 3500 lbs of reconnaissance equipment). For the present I think we can consider this the maximum attainable speed of any possible carrier aircraft.

At the very least, some sort of rocket assist will be needed to accelerate a scramjet vehicle to Mach 5-7 (minimum operating range of a scramjet). This will add to the complexity - and weight - of the orbital vehicle. Additionally, it seems likely that rocket assist will be needed to attain final orbital velocity - a further complication and added weight.

It seems that, for now, an air launch of a rocket powered orbital vehicle is the most feasible approach.

Chris
 
H

halman

Guest
I just got bitten by the 'Boeing 797' hoax, but discovered that there is a germ of truth to it. See

http://en.wikipedia.org/wiki/Blended_wing_body

This design comes close to what I have envisioned for the carrier wing, although the engines would have to be under the vehicle, not on top at the rear.

I find the obsession with exotic propulsion technology, such as the scram jet, to be a little discouraging. Good old fashioned rockets will work, quite well, actually, and they are available right now. It is not that I am against new technology, but I am anxious to see us regain our ability to reach space, and waiting for something like the scram jet to be perfected could delay that process by 20 years or more.

What many people don't seem to understand is that research and development will increase dramatically once we establish a commercial presence in space. It is all very well to talk about building single-stage to-orbit vehicles, and Mars exploration craft, and such, but those kinds of things will be enormously expensive, and getting someone to foot the bill will be hard unless we are already reaping benefits from space exploration that can be measured in dollars.

Think of the first transcontinental railroad. Most people believe that it was built to make transportation to California quick and affordable, and that was the justification given to the public at the time. But the real reason was the granting of all the land on either side of the right-of-way for 5 miles to the railroad companies. They got a swath of land ten miles wide for hundreds of miles. All of the gold that came out of California was worth a fraction of the worth of that land.

Once a way is found to get people into space cheaply and reliably, the launch industry will see a huge increase in business, as large corporations put their private space stations into orbit. Dow Chemical, General Electric, Westinghouse, DuPont, and a long list of names most people would not recognize, are anxious to begin experimenting in zero gravity. But they need to get their people up there. They are not interested in making discoveries which will become public property, which is the case with the International Space Station. They are not interested in having some astronaut conducting their research. These companies want their people aboard their space stations to make the breakthroughs, secure the patents, and beat the competition in the race to bring new products to market.

Once we reach that stage, the future of space exploration is assured. When wealth is being created by new products which can only be made in space, the money for development of advanced propulsion systems will go from a trickle to a waterfall. As we open up the Moon for development, money for missions to other planets will become abundant. But we have to get business up and running in space to be certain that space will not be abandoned. Relying on government funding for missions to the Moon or to Mars is a recipe for failure. When we give the private sector a reason to want to travel between the planets, progress will be rapid.

This may seem crass and cynical, but it is the reality as I see it.
 
R

rockett

Guest
halman":1bpwhx4a said:
I just got bitten by the 'Boeing 797' hoax, but discovered that there is a germ of truth to it. See

http://en.wikipedia.org/wiki/Blended_wing_body

This design comes close to what I have envisioned for the carrier wing, although the engines would have to be under the vehicle, not on top at the rear.

It reminded me of some of the early Shuttle carrier concepts:
http://www.astronautix.com/lvs/shuttle.htm
http://upload.wikimedia.org/wikiped...concepts.jpg/300px-Space_Shuttle_concepts.jpg

Then from the 50s there were:
BOMI
http://www.astronautix.com/craft/bomi.htm
http://www.fantastic-plastic.com/BellBoMiMX-2276Page.htm

Orbital Rocket
http://www.fantastic-plastic.com/MONOGRAM ORBITAL ROCKET PAGE.htm (I had this one when I was a kid)
Passenger Rocket
http://www.fantastic-plastic.com/MONOGRAM PASSENGER ROCKET PAGE.htm

And of course the German Amerika bomber:
http://www.luft46.com/jhart/jhsang-4.jpg

Ahhh those were the days...
 
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csmyth3025

Guest
The blended wing may well offer the heavy lift capabiblity needed for for a carrier aircratft for air launch of an orbital vehicle. This may be a furture generation of the Spaceship Two concept. Time will tell.

Chris
 
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halman

Guest
rockett":207l9rnv said:
halman":207l9rnv said:
I just got bitten by the 'Boeing 797' hoax, but discovered that there is a germ of truth to it. See

http://en.wikipedia.org/wiki/Blended_wing_body

This design comes close to what I have envisioned for the carrier wing, although the engines would have to be under the vehicle, not on top at the rear.

It reminded me of some of the early Shuttle carrier concepts:
http://www.astronautix.com/lvs/shuttle.htm
http://upload.wikimedia.org/wikiped...concepts.jpg/300px-Space_Shuttle_concepts.jpg

Then from the 50s there were:
BOMI
http://www.astronautix.com/craft/bomi.htm
http://www.fantastic-plastic.com/BellBoMiMX-2276Page.htm

Orbital Rocket
http://www.fantastic-plastic.com/MONOGRAM ORBITAL ROCKET PAGE.htm (I had this one when I was a kid)
Passenger Rocket
http://www.fantastic-plastic.com/MONOGRAM PASSENGER ROCKET PAGE.htm

And of course the German Amerika bomber:
http://www.luft46.com/jhart/jhsang-4.jpg

Ahhh those were the days...

These designs all featured boosters that were rocket powered, I believe, primarily because the turbofan engine was still in its infancy. Also, composite materials had not been developed yet, so weight was still a problem.

In aviation, lift was the big problem to begin with, so multiple wings were used to compensate for the weak powerplants available. As engines became more powerful, and speeds went up, monowing designs began to appear. The drag associated with multiple wings caused them to be discontinued before World War II. As range became a factor, the swept wing came into play. As a result, our image of an aircraft is a single swept wing supporting a fuselage that protects the crew and cargo from the slipstream of 600 miles per hour.

But what if we are interested only in lift, not in speed or in range? It is conceivable that dual wing aircraft could be used for the carrier wing, so that the structural requirements imposed by a very long wing can be avoided. Or maybe a partial secondary wing, near the centers of the main wing.

Another development which did not play a part in the early shuttle designs was Boundary Layer Control, the manipulation of the airflow over the wing using exhaust gasses to 'fool' the air into behaving like the wing is moving faster than it actually is.

The design of the orbiter is fairly clear cut; a lifting body powered by rocket engines, perhaps with extendable wings to increase stability for landing. If the payload bay of the current shuttle were to be converted into tankage for propellants, and the resulting craft hauled to 50,000 feet, I am pretty sure that it could achieve orbit. But that design would be inefficient, because the engines are too powerful. Also, the current shuttle is considerably heavier than what is possible with modern composite material construction.

The real challenge lies in the carrier wing, because this involves building an aircraft such as has never before been seen, just as the White Knight was a radical departure from previous designs. We need to throw out all our preconceptions about what an airplane is, and start from scratch using aerodynamics, engine technology, and whatever else we can to design the carrier wing. Just the existence of the modern turbofan is a game changer, because the new, high-bypass engines are producing amazing amounts of thrust for their weight.

But it is essential to keep the demands on the system to the minimum. What made the space shuttle such a poor launch system was the design requirements which exceeded simply getting a few people into a very low orbit. The Air Force requirements blew the original designs out of the water, by insisting that very heavy payloads could be inserted in orbits much higher than is necessary simply for crew transfer to another vehicle. What really makes me sad is that the Air Force abandoned the shuttle shortly after it became operational, which left the program looking like a bunch of idiots.
 
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csmyth3025

Guest
On the subject of the x-33/VentureStar I recently viewed a NASA sponsored video on the x-33. The related text indicates that the x-33 was to be a 1/3 scale demonstration vehicle for the technologies to be used in the VentureStar (no payload indicated for the x-33). The video states that the LOX tanks for the x-33 were designed to hold 181,000 lbs of LOX. My calculation tells me that the liquid hydrogen needed to react with this amount of LOX would be 22,625 lbs. Even if no allowance were made for boil-off, the fuel alone for this craft would weigh almost 204,000 lbs.

Supposing that 1/2 of this fuel requirement could be eliminated by an air launch, a carrier aircraft would have to fly at least 100,000 lbs of fuel plus the mass of the x-33 itself to the launch point. I'm guessing that the VentureStar itself - air launched - would be about three times as massive.

This illustrates how far we have to go to construct a fully reuseable air-launch-to-orbit system.

Chris
 
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csmyth3025

Guest
Adding to my previous post about the x-33, I came across this tid-bit in Wikipedia:

"...A kerosene-liquid oxygen (RP-LOX)
single stage to orbit (SSTO) vehicle must have at
least a 94% propellant mass fraction..."

Applying this mass fraction to a ground-launched x-33 gives a total ignition weight of about 217,000 lbs. This leaves just 13,000 lbs. for the vehicle. Using hydrogen-LOX might improve this ratio - but I'm not sure that it would in a practical application, due to the added weight needed to contain and process the cryogenic liquid hydrogen.

Chris
 
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csmyth3025

Guest
Adding again to my post on the x-33, I found this information on the (now defunct) XB-70A:

Empty weight=210,000 lb, loaded weight=534,000 lb, max take-off weight=550,000 lb, service ceiling=77,000 ft, cruising speed= Mach 3

Assuming this aircraft took off with 100,000 lbs of fuel for itself, it could conceivably air launch the x-33.

Chris
 
J

js117

Guest
csmyth3025":2o0xphlh said:
Adding again to my post on the x-33, I found this information on the (now defunct) XB-70A:

Empty weight=210,000 lb, loaded weight=534,000 lb, max take-off weight=550,000 lb, service ceiling=77,000 ft, cruising speed= Mach 3

Assuming this aircraft took off with 100,000 lbs of fuel for itself, it could conceivably air launch the x-33.

Chris

I posted the information on the XB- 70 earlier in the post .
This was a top secret project called Blackstar.

Link http://www.spyflight.co.uk/blackstar.htm
 
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csmyth3025

Guest
js117":jeml8q0q said:
csmyth3025":jeml8q0q said:
Adding again to my post on the x-33, I found this information on the (now defunct) XB-70A:

Empty weight=210,000 lb, loaded weight=534,000 lb, max take-off weight=550,000 lb, service ceiling=77,000 ft, cruising speed= Mach 3

Assuming this aircraft took off with 100,000 lbs of fuel for itself, it could conceivably air launch the x-33.

Chris

I posted the information on the XB- 70 earlier in the post .
This was a top secret project called Blackstar.

Link http://www.spyflight.co.uk/blackstar.htm

The article you link to basically declares the Blackstar to be a hoax - or at least pure speculation.

Chris
 
E

EarthlingX

Guest
csmyth3025":2v74qxs6 said:
I've been reading the specifications for the canceled x-33 at this site:

http://www.aerospaceweb.org/aircraft/research/x33/

To my surprise, the fuel capacity is listed as 30,000 lbs of LOX and 180,000 lbs of liquid hydrogen. Are these numbers reversed or are my numbers reversed?
Chris
It is the expected oxidizer to fuel 1:6 ratio for this engine : http://www.astronautix.com/engines/rs2200.htm

Some more details and info :
Wiki : Lockheed Martin X-33
Wiki : Aerospike Engine

Wiki : Liquid rocket propellants
 
C

csmyth3025

Guest
EarthlingX":1vtdpokv said:
csmyth3025":1vtdpokv said:
I've been reading the specifications for the canceled x-33 at this site:

http://www.aerospaceweb.org/aircraft/research/x33/

To my surprise, the fuel capacity is listed as 30,000 lbs of LOX and 180,000 lbs of liquid hydrogen. Are these numbers reversed or are my numbers reversed?
Chris
It is the expected oxidizer to fuel 1:6 ratio for this engine : http://www.astronautix.com/engines/rs2200.htm

Some more details and info :
Wiki : Lockheed Martin X-33
Wiki : Aerospike Engine

Wiki : Liquid rocket propellants

Astronautix.com lists the Space Shuttle Main Engine (SSME) as having an oxidizer-to-fuel ratio of 6.00 - the same ratio given for the RS-2200. According to the Wikipedia article on the Space Shuttle, the specifications for the Shuttle's External Tank are, in part, as follows:


LOX tank

Length: 54.6 ft (16.6 m)
Diameter: 27.6 ft (8.4 m)
Volume (at 22 psig): 19,541.66 cu ft (146,181.8 US gal; 553,358 l)
LOX mass (at 22 psig): 1,387,457 lb (629,340 kg)
Operation Pressure: 20–22 psi (140–150 kPa) (gauge)
Intertank

Length: 22.6 ft (6.9 m)
Diameter: 27.6 ft (8.4 m)
LH2 tank

Length: 97.0 ft (29.6 m)
Diameter: 27.6 ft (8.4 m)
Volume (at 29.3 psig): 52,881.61 cu ft (395,581.9 US gal; 1,497,440 l)
LH2 mass (at 29.3 psig): 234,265 lb (106,261 kg)
Operation Pressure: 32–34 psi (220–230 kPa) (absolute)
Operation Temperature: −423 °F (−252.8 °C)[3]

The weight of LOX carried in the external tank is 5.92 times the weight of liquid hydrogen. This leads me to believe that when an oxidizer-to-fuel ratio is given as 6.00, the intended meaning is 6 parts oxidizer to 1 part fuel by weight.

Chris
 
E

EarthlingX

Guest
Official numbers :
NASA : The External Tank

Weight:
Empty: 78,100 pounds
Propellant:
1,585,379 pounds
Gross: 1,667,677 pounds
Propellant Weight *
Liquid oxygen:
1,359,142 pounds
Liquid hydrogen:
226,237 pounds

Gross: 1,585,379 pounds
Propellant Volume *
Liquid oxygen tank:
143,060 gallons
Liquid hydrogen tank:
383,066 gallons
Gross: 526,126 gallons
Oxidizer to fuel mass ratio about 6:1, volume ratio 1:2.

Astronautix RS-2200
Oxidizer to Fuel Ratio: 6.00.

Edit. ah, my bad, should've copy/pasted :oops:

and of course, at least concerning the Shuttle, checked the official info first :
Space Shuttle : Overview

I searched over Lockheed Martin and Skunk Works, but found no technical info.
 

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