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http://hypersonic2002.aaaf.asso.fr/pape … r.pdf].pdf paper: "Fire tests of experimental scramjet in free stream - V.L. Semenov, et al., CIAM Moscow, Russia" with the results.
Whoa, look at the photo's of that engine, looks like something out of the X-Prize contenders' sheds. Russians surely have a way to go and do things on a shoestring-budget...
http://www.testpilot.ru/russia/tsiam/igla/igla.htm]More info (in Russian):"Needle" (GLL-VK) - Hypersonic Flying Laboratory
http://www.testpilot.ru/russia/lii/gll/31/gll31.htm]And another link in Russian:) AEE-31 (VLL-EXPERT)
Thanks to Fjodor Novozhilov on HobbySpace.
The Russian pages could be translated with this engine (appears as drop-down box on top of the page in the second link). I found the English translation readable but you'll be the judge.
http://www.translate.ru]http://www.translate.ru
Anatoli Titarev
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Are there any applications for scram-jets IN the martian atmosphere? Can't think of any, but flying probes have been proposed before and silly questions sometimes have fun/useful answers.
ANTIcarrot.
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As far as I know, Wickman Spacecraft & Propulsion Company got a contract to develop a jet engine for Mars that uses magnesium powder as fuel and CO2 from Mars atmosphere as oxidiser. (references: http://sbir.gsfc.nasa.gov/SBIR/abstract … .html]NASA and http://www.space-rockets.com/marsjet.html]WSPC) This is a turbojet engine with relatively low performance, not a SCRAM jet. Its advantage is that it uses a fuel that can be harvested from Mars soil together with Mars atmosphere.
I feel the greatest use of SCRAM jet technology will be access to orbit. Many "old time" rocket guys have argued for a "big dumb rocket"; that means an expendable launch vehicle. The argument is that Shuttle proved the cost of operation is just too high for a reusable system. However, a SCRAM jet vehicle changes all that. Several attempts to design a Shuttle replacement such as X-33/VentureStar or the latest Two-Stage-To-Orbit concepts are borderline economical, any significant cost overrun would make them cost more than an expendable launch vehicle. For example, when Lockheed Martin found the launch market wasn't as great as they hoped so looked for a way out of their financial participation in X-33, and found one. However, a hypersonic air-breathing vehicle can be the holy grail: Single Stage To Orbit (SSTO) Reusable Launch Vehicle (RLV). A vehicle that can take off and land on a runway of any airport large enough for a commercial jet airliner, and comes back with everything except fuel. The airport would have to be equipped with special fuel handling facilities for the rocket engines, but such a SSTO RLV could easily land at any airport and refuel with normal jet fuel to fly itself to a more equipped airport. The ability to land at any airport is a great safety feature. What would we call such a thing? It would fly like an aircraft with air-breathing engines for most of its flight, but it would also be a spacecraft. I would call it an aerospacecraft. We could build several aerospacecraft: a cargo ship that would operate like today's Shuttle, and a small space taxi to take 3 or 4 astronauts to the space station. Bulk cargo or satellite delivery might always be more efficient with a rocket, but a reusable aerospacecraft will be more cost effective than throwing away a spacecraft like Soyuz.
The catch is developing the technology. SCRAM jet engines have been proven in wind tunnels since Ronald Regan's X-30, and recently turbine based supersonic engines. The X-30 program identified problems integrating everything into a working aircraft. That's what the X-43A is all about. We need to continue development of supersonic combustion engines and hypersonic airframes if we ever expect to achieve cheap, reliable, safe, regular access to space.
Personally, I would like to see a passenger liner capable of carrying 100 colonists from Earth to LEO for transfer to a spacecraft destined for Mars.
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Robert or anyone.
Would it be possible to design a cold weather (i.e. Mars!) solid fuel rocket that mixed magnesium powder with dry ice (frozen CO2)? Build the thing inside a slightly pressurized freezer if the ambient Mars air temperature was too high.
Lace the magnesium powder with veins of frozen CO2 and igniter cords. Keep cold until launch and then launch from Mars surface to Mars orbit.
= = =
Off thread, but follows from Robert's post.
:;):
Give someone a sufficient [b][i]why[/i][/b] and they can endure just about any [b][i]how[/i][/b]
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The same company has developed a http://www.space-rockets.com/marsprop.html]Carbon Dioxide/Magnesium powder rocket engine. I dont think it uses dry ice, though. I mentioned the jet engine since it's the only jet I know developed for Mars.
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What would we call such a thing? It would fly like an aircraft with air-breathing engines for most of its flight, but it would also be a spacecraft. I would call it an aerospacecraft.
Actually there is a word for it already... it would be a tried-and-true, dyed-in-the-wool, genuine honest-to-god Spaceplane.
The concept for a SSTO scramjet to near-orbital velocities is fairly sound, but the technology is just not there yet... today you can possibly make a plane do Mach-10, perhaps a little faster, which is a bit less than half way to orbit. You need to start talking speeds in the Mach-20 region before the orbital insertion burn becomes small enough.
There are a few hurdles to jump before such an craft can be pushed to such speeds, mainly the intense heat, drag, and fuel volume. The former two can be partially overcome by using the fuel to cool the skin and boost the efficency, and the latter mitigated by using slush hydrogen (perhaps spiked with metal powder for kick), then you could get pretty close to where a small hydrogen aerospike engine could go the rest of the way... the rest is engineering, tweaking the thing, improved thermal protection, and structure lightening (composit fuel tanks).
Barring the invention of the space elevator, with its dubious economics, a spaceplane is the only way to move people off Earth in quantity and the only way possible to move materials more efficently than lobbing a humongus rocket that took weeks to prepare and weeks between launches and only handles giant payloads.
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Hmmm Mg/CO2 rockets... why bother with using dry ice? Its brittle and it sublimates readily, making it bad for solid rockets. So, don't use solid CO2... if you put it under mild pressure, CO2 can be liquified you know.
[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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Hey, we're in agreement. Yes, spaceplane technology needs work. Giving up just because it isn't finished already is not reasonable. Cindy reported the X-43A will be flown once more to demonstrate mach 10. Horay! Next we need X-43C reinstated. Then examine results from those programs before designing the next step. Thomas Edison said "Genius is 1% inspiration and 99% perspiration."
However, I argue an aerospike engine isn't necessary. The advantage of aerospike is its fairly even specific impulse from the 1 atmosphere pressure at the surface to vacuum in space. A traditional rocket with bell cone operates efficiently over a relatively small pressure range. However, if the SCRAM jet engine can get the spaceplane most of the way out of the atmosphere, then the slight air pressure remaining could be low enough to make a rocket with bell cone more efficient.
To keep engine mass down you probably want a combined cycle engine: a single engine that can operate with subsonic combustion, supersonic combustion, air/LOX mixture, and LOX/LH2 rocket.
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A scramjet spaceplane will be spending a good deal of its acent in the thicker atmosphere though, in order to use the oxygen to power the engine. Unless the spaceplane was to just coast out of the atmosphere after accelerating to Mach-20 where it would be slowed by drag without the engine running, then the orbital insertion rocket will need to operate in the air and in space efficently... so an Aerospike would be good to maximize Isp over the acent regieme.
Doubling up on engines sounds good on paper, but the Scramjet's design is so fundimentaly different than a turbine engine or a rocket engine that I don't think that it is possible to combine them all really. One possible way around it is to combine the turbine engines for takeoff and the orbital insertion rocket, which is possible, but I think its questionable if it would save much mass (The RL-10 rocket engine weighs only a few hundred pounds).
[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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The same company has developed a http://www.space-rockets.com/marsprop.html]Carbon Dioxide/Magnesium powder rocket engine. I dont think it uses dry ice, though. I mentioned the jet engine since it's the only jet I know developed for Mars.
Robert, thank you for the link.
I have just finished reading his argument why PVC tubes are just as safe as aluminum for amateur solid rocket applications.
Any reason why a large made-on-Mars PVC tube would not work for launching an uncrewed payload to low Mars orbit using Mg/CO2 solid rockets? 100% made-on-Mars lift would seem to be a pre-condition to any viable export business.
Once in low Mars orbit, a cycling solar ion tug, using Lo road trajectories, could dock with the payloads and transfer to LEO or L1.
Give someone a sufficient [b][i]why[/i][/b] and they can endure just about any [b][i]how[/i][/b]
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I can think of a few...
One of the big reasons that amerature solid rocket motors explode is when the fuel grain cracks, which greatly increases the surface area and speeds up combustion. It speeds it up so much that the increased pressure causes the engine casing to burst and the whole engine to explode.
Dry ice is very brittle and tends to sublimate on its own. It is not stable except at very low temperatures, and even a small mishap or manufacturing defect would cause the fuel grain to crack and the whole thing to go up. A better idea would be to simply mix finely ground Magnesium with liquified CO2 into a slurry and pump that into a liquid engine. The Shuttle SRBs and most solid rockets on Earth use butadiene RUBBER as a binder to avoid fuel grain cracking.
Using PVC or any other polymer on Mars for general purpose expendable construction is simply not going to happen. To make polymers you need a substantial quantity of Hydrogen and in the case of PVC you need Chlorine too, things that are NOT plentiful in the soil.
Making a giant amerature-style solid rocket to launch bulk cargo into MEO makes no sense... it is a much better idea to simply build a DC-X style RLV powerd by Mg/LCO2 or CH4/LOX.
[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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I know that follow up experiments from the airforce were to try and use jet fuels in the scram jet engine.
Also would not a modulated system of kerosene and lox with scram jet technology be of benefit at lift off if one starts with lox and then switches over to mixing in the compressed air after launch and then to finally just scram intake air.
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Here is a resource on scramjet
http://www.tipmagazine.com/tip/INPHFA/v … type=ALERT
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Any reason why a large made-on-Mars PVC tube would not work for launching an uncrewed payload to low Mars orbit using Mg/CO2 solid rockets? 100% made-on-Mars lift would seem to be a pre-condition to any viable export business.
In 2000/2001 I looked at how to make materials from Mars resources. Of course, Robert Zubrin's book "The Case for Mars" is what gave me the idea. I posted how to make plastics, including PVC and acrylic, http://chapters.marssociety.org/winnipe … .html]here.
You could use Mg/CO2 as John Wickman did. Dry ice would tend to sublimate in warm day temperatures. Jim Benson of SpaceDev developed an acrylic/NO hybrid rocket. It uses acrylic solid with nitrous oxide as a gaseous oxidizer. Solid magnesium metal tends to form magnesium oxide as a solid coating, preventing further magnesium from reacting; that's why it has to be a powder. So a solid/gas hybrid using magnesium wouldn't work.
However, since Mars has so many resources we can use any fuel mixture you can think of. Subsurface permafrost at the poles is extensive, and on the plateau of Arabia Terra. A human outpost needs as much atmosphere as possible for radiation protection so we really want the bottom of a valley. I'm waiting for the data from the ground penetrating radar of Mars Express. If we find subsurface permafrost in an equatorial valley, that's where we send astronauts.
With enough permafrost we can make LH2/LOX fuel. LH2 is a hard cryogenic, meaning it must be kept very cold to prevent boil-off, so it isn't very storable. We may be better off with methane/LOX. Either way, we can make rocket fuel from 100% Mars resources.
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On Mars we will still need to have motorized vehicles to travel the surface and that still requires fuels research.
Also solar power is less effective on Mars than on earth for the same size cell panels.
Nuclear may be a possibility but how will one construct such reactors from Mars Materials with no mining or smelting operations.
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A solid Magnesium/LCO2 rocket wouldn't be hamperd by the Magnesium oxidizing because there is no oxygen on Mars. I don't think that it would form a Magnesium Carbonate coating anywhere near as readily as an oxide one particularly at such low pressures and temperatures, so exposing the engine to the Martian atmosphere shouldn't be an issue.
[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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This link will get you lots of other alternatives.
http://www.space-rockets.com/wspc.html
Left side bar on web page:
Earth To Orbit
PSAN-I Ammonium Nitrate & Propellants
SHARP Spaceplane
Small Launch Vehicle
Sounding Rockets
Liquid Oxygen Monopropellants
Earth - Lunar Corridor
Lunar Soil Propellant (LSP)
Shuttle Excursion Module (SEM) ™
Shuttle Landing Module (SLM) ™
Lunar Bases & Lunar Concrete
Mars
Mars Rocket Engines
Mars Jet Engines
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US ‘ready to fight in space if we have to’, says military official | Threat posed by ‘provocative’ Russia and China has left US no choice but to prepare for orbital skirmishes
https://www.theguardian.com/science/202 … y-official
China’s Mysterious Space Plane Returns to Earth
https://www.scientificamerican.com/arti … -to-earth/
Specialists speculate that it might be similar to a US spaceplane, and it could have research or military uses.
https://www.nature.com/articles/d41586-023-01639-0
"NUKEM" The Board Game Commercial- as seen in RoboCop (1987)
https://www.youtube.com/watch?v=ZYGa9KZOy7c
Last edited by Mars_B4_Moon (2023-05-28 15:32:51)
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