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I was at the www.space.com site to find this which I liked, and then did some related searching and thinking:
http://www.space.com/16378-hybrid-rocke … t-spg.html
Quote:
A new hybrid rocket motor fired up Friday (June 29), demonstrating technology that its builders say could lead to efficient, alternative-fuel launch vehicles down the road.
California-based Space Propulsion Group, Inc. (SPG) test-fired the 22-inch-wide (56-centimeter) liquid oxygen/paraffin motor for about 20 seconds Friday, blasting a streak of bright flame into the air at the company's testing facility in Butte, Mont.
The trial was the fifth for this particular motor, SPG officials said, and it demonstrated a flight-weight version of the design.
The company says future propulsion systems using the motor's hybrid technology have the potential to be five to 10 times cheaper than existing rockets. And the paraffin fuel has the added benefit of being non-toxic, officials said.
"We believe propulsion drives the cost of access to space and that complexity generally drives propulsion system cost," SPG president and chief technical officer Arif Karabeyoglu said in a statement after the test-fire. "By using a commercially available paraffin-based fuel, we have created an economically viable alternative that could significantly reduce the price of space accessibility, as well as help preserve the environment."
Hybrid rocket motors use propellants that are in two different states of matter, as opposed to purely liquid or solid rockets.
Proponents of hybrid technology claim that it combines the advantages of the other two types, offering the simplicity of solid systems and the safety of liquid rockets. (Solid rockets, such as the boosters that helped loft NASA's now-retired space shuttle, generally can't be shut off once they've been lit.)
Hybrid rockets are playing a large role in the burgeoning private spaceflight industry. Virgin Galactic's suborbital SpaceShipTwo vehicle employs hybrid motors, as does Sierra Nevada's Dream Chaser, a mini-shuttle that's in the running to transport NASA astronauts to and from the International Space Station.
Follow SPACE.com on Twitter @Spacedotcom. We're also on Facebook and Google+.
Quote Again specifically:
The company says future propulsion systems using the motor's hybrid technology have the potential to be five to 10 times cheaper than existing rockets. And the paraffin fuel has the added benefit of being non-toxic, officials said.
Paraffin
http://en.wikipedia.org/wiki/Paraffin
Quote:
Paraffin waxParaffin wax (or simply "paraffin", but see alternative name for kerosene, above) is mostly found as a white, odorless, tasteless, waxy solid, with a typical melting point between about 46 and 68 °C (115 and 154 °F),[4] and having a density of around 0.9 g/cm3.[5] It is insoluble in water, but soluble in ether, benzene, and certain esters. Paraffin is unaffected by most common chemical reagents but burns readily.[6]
Pure paraffin wax is an excellent electrical insulator, with an electrical resistivity of between 1013 and 1017 ohm metre.[7] This is better than nearly all other materials except some plastics (notably Teflon). It is an effective neutron moderator and was used in James Chadwick's 1932 experiments to identify the neutron.[8][9]
Paraffin wax is an excellent material to store heat, having a specific heat capacity of 2.14–2.9 J g−1 K−1 (joule per gram kelvin) and a heat of fusion of 200–220 J g−1.[10] This property is exploited in modified drywall for home building material: a certain type (with the right melting point) of wax is infused in the drywall during manufacture so that, when installed, it melts during the day, absorbing heat, and solidifies again at night, releasing the heat.[11] Paraffin wax phase change cooling coupled with retractable radiators was used to cool the electronics of the Lunar Rover.[12] Wax expands considerably when it melts and this allows its use in wax thermostatic element thermostats for industrial, domestic and, particularly, automobile purposes.[13][14]
In industrial applications, it is often useful to modify the crystal properties of the paraffin wax, typically by adding branching to the existing carbon backbone chain. The modification is usually done with additives, such as EVA copolymers, microcrystalline wax, or forms of polyethylene. The branched properties result in a modified paraffin with a higher viscosity, smaller crystalline structure, and modified functional properties. Pure paraffin wax is rarely used for carving original models for casting metal and other materials in the lost wax process, as it is relatively brittle at room temperature and presents the risks of chipping and breakage when worked. Soft and pliable waxes, like beeswax, may be preferred for such sculpture, but "investment casting waxes," often paraffin-based, are expressly formulated for the purpose
So, I can see making old fashoioned "Potted" electircal devices if necessary. (You never know what emergency might happen)
Or using the stuff to maintain comfortable/habitible conditions in a habitat, per temperature regulation. It apparently was already used on the Moon for a cooling fluid, how about a heating fluid on Mars?
As a Rocket fuel.
TwinBeam mentioned crash-landing raw materials on another thread, I mentioned a "chain method" also on that thread, but it has other traffic of another nature, and this would step on that so I am starting this thread.
It seems to me that it would be a good candidate for hard landing/crash landing.
If packets of it were strapped on to the sides of a lander, and the lander had a spin at the time of release, the the bags of paraffin would eject from the lander and reduce it's load. If there were air/Nitrogen bubbles in the plastic phase paraffin, then upon impact, the air bubbles would absorb some of the shock, and perhaps keep the bags from bursting. Even if they burst, I am inclinded to think that the paraffin would largely be usible for a reasonable period of time, with cleaning.
I am wondering if instead of bringing Hydrogen to Mars, and extracting Oxygen from the atmosphere from it, it would be better to use paraffin as the fuel, and then simply extract Oxygen from CO2 directly, and casting away the CO remnant?
Hydrogen would be hard to deliver to Mars as a liquid. Water would be expensive to deliver to Mars, since you are delivering a lot of Oxygen.
If Parafin can be eject-landed, and Oxygen pulled directly from the CO2, then the humans would simply pick up the solid pieces of bagged paraffin, and use it during the mission for what utility it had, and the reuse it as a fuel to get to orbit.
The following is not part of this topic, but it is interesting. Maybe later:
http://www.space.com/16367-private-moon … almaz.html
Last edited by Void (2012-07-01 08:44:30)
I am starting to ask seriously "Why do I do this?"
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I was at the www.space.com site to find this which I liked, and then did some related searching and thinking:
http://www.space.com/16378-hybrid-rocke … t-spg.html
Quote:
A new hybrid rocket motor fired up Friday (June 29), demonstrating technology that its builders say could lead to efficient, alternative-fuel launch vehicles down the road.
California-based Space Propulsion Group, Inc. (SPG) test-fired the 22-inch-wide (56-centimeter) liquid oxygen/paraffin motor for about 20 seconds Friday, blasting a streak of bright flame into the air at the company's testing facility in Butte, Mont.
The trial was the fifth for this particular motor, SPG officials said, and it demonstrated a flight-weight version of the design.
The company says future propulsion systems using the motor's hybrid technology have the potential to be five to 10 times cheaper than existing rockets. And the paraffin fuel has the added benefit of being non-toxic, officials said.
"We believe propulsion drives the cost of access to space and that complexity generally drives propulsion system cost," SPG president and chief technical officer Arif Karabeyoglu said in a statement after the test-fire. "By using a commercially available paraffin-based fuel, we have created an economically viable alternative that could significantly reduce the price of space accessibility, as well as help preserve the environment."
Hybrid rocket motors use propellants that are in two different states of matter, as opposed to purely liquid or solid rockets.
Proponents of hybrid technology claim that it combines the advantages of the other two types, offering the simplicity of solid systems and the safety of liquid rockets. (Solid rockets, such as the boosters that helped loft NASA's now-retired space shuttle, generally can't be shut off once they've been lit.)
Hybrid rockets are playing a large role in the burgeoning private spaceflight industry. Virgin Galactic's suborbital SpaceShipTwo vehicle employs hybrid motors, as does Sierra Nevada's Dream Chaser, a mini-shuttle that's in the running to transport NASA astronauts to and from the International Space Station.
Follow SPACE.com on Twitter @Spacedotcom. We're also on Facebook and Google+.
Quote Again specifically:
The company says future propulsion systems using the motor's hybrid technology have the potential to be five to 10 times cheaper than existing rockets. And the paraffin fuel has the added benefit of being non-toxic, officials said.
Paraffin
http://en.wikipedia.org/wiki/Paraffinhttp://upload.wikimedia.org/wikipedia/c … raffin.jpg
Quote:
Paraffin waxParaffin wax (or simply "paraffin", but see alternative name for kerosene, above) is mostly found as a white, odorless, tasteless, waxy solid, with a typical melting point between about 46 and 68 °C (115 and 154 °F),[4] and having a density of around 0.9 g/cm3.[5] It is insoluble in water, but soluble in ether, benzene, and certain esters. Paraffin is unaffected by most common chemical reagents but burns readily.[6]
Pure paraffin wax is an excellent electrical insulator, with an electrical resistivity of between 1013 and 1017 ohm metre.[7] This is better than nearly all other materials except some plastics (notably Teflon). It is an effective neutron moderator and was used in James Chadwick's 1932 experiments to identify the neutron.[8][9]
Paraffin wax is an excellent material to store heat, having a specific heat capacity of 2.14–2.9 J g−1 K−1 (joule per gram kelvin) and a heat of fusion of 200–220 J g−1.[10] This property is exploited in modified drywall for home building material: a certain type (with the right melting point) of wax is infused in the drywall during manufacture so that, when installed, it melts during the day, absorbing heat, and solidifies again at night, releasing the heat.[11] Paraffin wax phase change cooling coupled with retractable radiators was used to cool the electronics of the Lunar Rover.[12] Wax expands considerably when it melts and this allows its use in wax thermostatic element thermostats for industrial, domestic and, particularly, automobile purposes.[13][14]
In industrial applications, it is often useful to modify the crystal properties of the paraffin wax, typically by adding branching to the existing carbon backbone chain. The modification is usually done with additives, such as EVA copolymers, microcrystalline wax, or forms of polyethylene. The branched properties result in a modified paraffin with a higher viscosity, smaller crystalline structure, and modified functional properties. Pure paraffin wax is rarely used for carving original models for casting metal and other materials in the lost wax process, as it is relatively brittle at room temperature and presents the risks of chipping and breakage when worked. Soft and pliable waxes, like beeswax, may be preferred for such sculpture, but "investment casting waxes," often paraffin-based, are expressly formulated for the purpose
So, I can see making old fashoioned "Potted" electircal devices if necessary. (You never know what emergency might happen)
Or using the stuff to maintain comfortable/habitible conditions in a habitat, per temperature regulation. It apparently was already used on the Moon for a cooling fluid, how about a heating fluid on Mars?
As a Rocket fuel.
TwinBeam mentioned crash-landing raw materials on another thread, I mentioned a "chain method" also on that thread, but it has other traffic of another nature, and this would step on that so I am starting this thread.
It seems to me that it would be a good candidate for hard landing/crash landing.
If packets of it were strapped on to the sides of a lander, and the lander had a spin at the time of release, the the bags of paraffin would eject from the lander and reduce it's load. If there were air/Nitrogen bubbles in the plastic phase paraffin, then upon impact, the air bubbles would absorb some of the shock, and perhaps keep the bags from bursting. Even if they burst, I am inclinded to think that the paraffin would largely be usible for a reasonable period of time, with cleaning.
I am wondering if instead of bringing Hydrogen to Mars, and extracting Oxygen from the atmosphere from it, it would be better to use paraffin as the fuel, and then simply extract Oxygen from CO2 directly, and casting away the CO remnant?
Hydrogen would be hard to deliver to Mars as a liquid. Water would be expensive to deliver to Mars, since you are delivering a lot of Oxygen.
If Parafin can be eject-landed, and Oxygen pulled directly from the CO2, then the humans would simply pick up the solid pieces of bagged paraffin, and use it during the mission for what utility it had, and the reuse it as a fuel to get to orbit.
The following is not part of this topic, but it is interesting. Maybe later:
http://www.space.com/16367-private-moon … almaz.html
Interesting - I do favour the "rough landing" as I would call it of "non-delicates". However, I see no reason to add to the mass burden if we can use ISRU. I really don't think heating habitats will be a problem if we land lightweight PV panels. Burning paraffin on a constant basis would require monitoring.
There may be some argument for landing it on the first mission if we want to be sure of a return fuel supply I guess.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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I'd rather just solve the straightforward lander problem, than to try to develop ways and means of crash-landing stuff. Not everything is "hard" enough to crash and survive. We certainly are not. Most of our equipment isn't, either.
It's maybe low-level retro thrust during entry to raise the altitude at which you go "merely" supersonic, and then high-level retro thrust from there to touchdown. Maybe a supersonic chute or ballute might help reduce fuel burn a tad, maybe not. I'm not at all "scared" of making hypersonic retro thrust a good working tool. The only real issues are retro plume aerodynamic stability and holes in the heat shield through which to thrust. Both have solutions, just not yet tried.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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I respect all opinions on this, but if such engines are actually 5-10 times cheaper to use, it has to be attractive.
Oh, I don't plan to burn paraffin to heat the structure Louis. It is a fluid that retains heat well, and can be melted with solar heat, pumped into the tanks as warm, and retain heat overnight. Maybe the people would sleep on the tanks, with a blanket above them.
So after the humans arrive, they load up the pariffin tanks with the stuff strewn about outside, and start melting it with solar heat. Later when the mission is over, it is fuel, for the burn up to orbit.
And by the way the plastic bags that would hold the paraffin would then be recycled to 3D printers to make stuff.
Paraffin wax is an excellent material to store heat, having a specific heat capacity of 2.14–2.9 J g−1 K−1 (joule per gram kelvin) and a heat of fusion of 200–220 J g−1.[10] This property is exploited in modified drywall for home building material: a certain type (with the right melting point) of wax is infused in the drywall during manufacture so that, when installed, it melts during the day, absorbing heat, and solidifies again at night, releasing the heat.[11] Paraffin wax phase change cooling coupled with retractable radiators was used to cool the electronics of the Lunar Rover.[12] Wax expands considerably when it melts and this allows its use in wax thermostatic element thermostats for industrial, domestic and, particularly, automobile purposes.[13][14]
My concern is that I constantly hear how hard it is to land a big payload. Well, if you dump off "Ballast" in the form of useful materials, then you lighten the payload before the thump-down, allowing additional slowing with the engines. So, maybe you get to have your cake and eat it to. Not bad from my thinking.
I agree that getting stuff from the locality is a nice plan, but you won't be getting beef jerky right away. I wonder how hard a stick of beef jerky can hit the Martian surface and still be food?
Now, if your beef jerky were in the form of a chain, including plant fiber and also a digestable glue, you could go drag it back to the camp, cut pieces off, put them in a sealed pot of water, and dump that into a hot paraffin bath, and go out to work. I get the idea that you might want your people to eat something more basic, but still, for moral, heated food might be better some times. I might be a little concerned on how you do the dishes however. How do you prevent food poisioning? Maybe it can be solved.
As for Steel, yes you might collect iron, but before you do that you need tools, Steel slammed hard to the surface from a high drop may or may not survive as chain. Parts might be good and parts might be broken and mangled. Well join the good parts to make such an amount of chain as you need (Not that much I expect), and take the other pieces, and heat them in a solar focus, and shape it into tools you will need to gather ISRU materials and to process them. You cannot start with rocks and expect to make goods, you have to have some starter tools, and some raw materials you bring to make more tools with those tools. It is not necessary to soft land the processed materials such as chain and beef jerky (Or some other food with similar properties), it does make sense that they must be retrievable, so I think dropping them from one of the main delivery vehicles is the best, since that way they will not be miles away (I hope).
I see it as a cone of provision. Soft land the starter tools, hard drop the materials for the second wave of tools, gather local materials for the third wave of tools.
I also wonder if it would be possible to manufacture Paraffin from Phobos and Demos? Carbon, Hydrogen, Nitrogen? And then eventually manufacture it on Mars.
It does make sense to me that that material can be easily stockpiled. I am not sure about easily manufactured however.
I actually hope I am not exasperating you Rocket Man.
Some times I just have to do what I do, until an imovable object stops me, such as reality.
Last edited by Void (2012-07-01 19:04:50)
I am starting to ask seriously "Why do I do this?"
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OK, I'm not sure that anything of any size and utility to people on Mars can be truly "crash landed", meaning what they used to call a hard landing: no deceleration of any kind after the hypersonics are over. Mach 3 + impact pretty much dissociates matter as we know it, here or anywhere else. The "hypersonics" are typically over in the M 3-5 range.
On the other hand, those two small rovers used airbags to survive terminal-velocity parachute delivery. Unlike Earth, low-altitude terminal velocity on Mars with any practical chute is pretty close to local Mach 1. That kind of thing does not scale up very well, since mass grows as size cubed, while area (as for chutes) grows only as size squared.
Paraffin wax is a useful material, probably also to folks on Mars. Just like steel and a lot of other things. I really believe a M3+ impact is violent enough to vaporize even large quantities of it, based on kinetic impactor weapons tests I have seen. So, I think we might have to do better than supersonic crash landings.
On the other hand, there's lots of things that could survive a high-subsonic impact, even without an airbag. That might be a fruitful concept to explore. Surface sound speed on Mars is on the order of 240 m/sec, much slower than the 300+ here. Different gas, and much colder, too.
A 340-ish m/sec "terminal velocity" is very definitely still well supersonic on Mars. You do that with ribbon chutes or similar, not slow terminal velocity cargo chutes.
The Spacex Dragon set up with its Super-Draco thrusters could actually land stuff one-way on Mars. Those thrusters are canted 45 degrees or so, and exit from ports on the capsule's sides, not through the heat shield. My guess is that they plan on using small amounts of thrust during the hypersonics to put its end nearer 10 km altitude than 1 km, and then go to high thrust for deceleration-to-touchdown at reasonable net gee. Based on what I've read about Dragon, a wild guess for deliverable cargo mass this way might be 2-3 tons. But it'll require bigger thruster fuel tanks inside the capsule, for sure.
There's about a 30% drop in net performance (thrust and Isp) for rockets canted 45 degrees. It's the cosine factor effect. I do believe some cant angle is required to maintain hypersonic and supersonic plume stability so that attitude control is not upset by screwed-up unsteady aerodynamics. However, I also think that 10-15 degrees cant angle might serve as very stable, although that would require firing your thrusters through the heat shield during the hypersonics.
That through-the-heat-shield notion sounds very scary, because of what happened to shuttle Columbia's wing. But you have to remember, that structure was unsealed and admitted a whopping lot of throughflow through the hole in the leading edge. If on the other hand, the compartment containing your thruster is otherwise sealed to admit no throughflow, then there is no danger whether you are firing through the open port in the heat shield or not. The static gas column in the compartment is itself far better insulation and protection than any heat shield could ever be. The key to this concept is "static gas column". You leak, you die. But this can actually be done, and already was with the Gemini B heat shield test 4 decades ago.
Gemini B was a Gemini variant intended for the USAF MOL program that ended up being cancelled after 1 unmanned flight. There was a crew access hatch through the heat shield into the MOL station. It was a removable plug hatch cover. The gap around that plug hatch in the heat shield is exactly the static gas column effect I am talking about. It worked fine.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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I hold your opinion in high regaurd. You did not dismiss the idea out of hand, that is nice.
Anyway, facts are facts, and I believe that you have them understood quite well, beyond my abilities.
Dumping something off the ship just prior to landing is actually the only loophole I have noticed, that could defy the existing plans that are well thought out.
It is nice that you have the patience to consider it.
I am starting to ask seriously "Why do I do this?"
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Actually, dumping mass before touchdown is a very old and time-honored tradition. Lots of airplanes have dumped fuel before landing, for about half a century now.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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I like the idea, personally. I had thought of something similar, for harder resources like already-alloyed metals (making iron/steel on site wouldn't be difficult, given enough of an oxygen sink... I do it all the time in my forge at home, reducing iron oxide into iron at high temperatures in a charcoal fire... on Mars you'd use an oxygen grabber like carbon, and an induction furnace, though) but hadn't thought about dropping softer items.
What if the ParaffinPak(tm) (just for fun) was a big sheet wrapped around the spacecraft, or a long ribbon? Seems to me it could aerobrake from a relatively stable orbit without gaining too many BTU's to maintain containment. Say, an aluminum foil pack around a paraffin sheet. Kind of like a CapriSun drink, or any number of freeze-dried or vacuum-sealed foods in foil packs.
There's also stainless steel foils that would do quite well at elevated temperatures, but you'd have to worry about boiling the paraffin and rupturing the container.
Anyhow, it would seem like the whole thing could be made to have a ridiculously low terminal velocity. Slow down to low supersonic speeds, shed the paraffin blanket like a sabot on an artillery shell, and let the whole thing drift down rather gently over the course of 3/4 of an orbit or so. Or as above, drop it off prior to significant aerobraking, and let it skim the atmosphere for 2-3 orbits before it starts plunging to its doom.
Lots of numbers to be run to see exactly how hot it would get - I'm not sure if it's possible to aerobrake with something like an airfoil shape that would be effective at such high altitudes, but to repeatedly skip along the atmosphere and bleed kinetic energy a little at a time, never quite heating the material beyond its boiling point, and then descend when it's slow enough that the stagnation temperature is well below the boiling point to begin with.
Then there's always semi-active cooling - set up the foil bag so it's rigid under the pressure of expanded, molten paraffin, and design it so that it self-circulates the paraffin through the structure and dumps heat on the top side, and picks it up on the leading edge and bottom where it's hottest, and just build in expansion areas to keep the whole thing from rupturing and turning into a streak of fire across the sky.
(That in itself is an interesting thought... would the paraffin have anything to react with in a nearly pure CO2 atmosphere? would there be enough reactive species from the shock wave to "ignite" the leaking liquid, or would you be spilling a hundred-mile-long strand of paraffin droplets across the surface?
*ponders*
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Ok, so luck of the draw, I get an email from a friend of mine. I copy it below, as the NASA press release. Neat stuff. Anyone want to tag along?
RELEASE: 12-236
NASA HYPERSONIC INFLATABLE TECH TEST SET FOR VIRGINIA LAUNCH JULY 21
WALLOPS ISLAND, Va. -- NASA Space Technology Program researchers will
launch and deploy a large inflatable heat shield aboard a rocket
travelling at hypersonic speeds this weekend during a technology
demonstration test from the agency's Wallops Flight Facility on
Wallops Island, Va.
NASA has four consecutive days of launch opportunities for the
agency's Inflatable Re-entry Vehicle Experiment (IRVE-3), starting
July 21, with the liftoff window from 6 a.m. to 8 a.m. EDT each day.
The test is designed to demonstrate lightweight, yet strong,
inflatable structures that could become practical tools for
exploration of other worlds or as a way to return items safely to
Earth from the International Space Station. During this technology
demonstration test flight, NASA's IRVE-3 payload will try to re-enter
Earth's atmosphere at hypersonic speeds -- Mach 5, or 3,800 mph to
7,600 mph.
"As we investigate new ways to bring cargo back to Earth from the
International Space Station and innovative ways to land larger
payloads safely on Mars, it's clear we need to invest in new
technologies that will enable these goals," said Michael Gazarik,
director of NASA's Space Technology Program. "IRVE-3 is precisely the
sort of cross-cutting technology NASA's Space Technology Program
should mature to make these future NASA and commercial space
endeavors possible."
The IRVE-3 experiment will fly aboard a three-stage Black Brant XI
launch vehicle for its suborbital flight. The payload and the heat
shield, which looks like a large, uninflated cone of inner tubes,
will be packed inside the rocket's 22-inch-diameter nose cone. About
six minutes after launch, the rocket will climb to an altitude of
about 280 miles over the Atlantic Ocean.
At that point, the 680-pound IRVE-3 will separate from the rocket. An
inflation system similar to air tanks used by scuba divers will pump
nitrogen gas into the IRVE-3 aeroshell until it becomes almost 10
feet in diameter. Instruments on board, including pressure sensors
and heat flux gauges, as well as cameras, will provide data to
engineers on the ground of how well the inflated heat shield performs
during the force and heat of entry into Earth's atmosphere.
After its flight, IRVE-3 will fall into the Atlantic Ocean about 350
miles down range from Wallops. From launch to splash down, the flight
is expected to take approximately 20 minutes.
"We originally came up with this concept because we'd like to be able
to land more mass and access higher altitudes on Mars," said Neil
Cheatwood, IRVE-3 principal investigator at NASA's Langley Research
Center in Hampton, Va. "To do so you need more drag. We're seeking to
maximize the drag area of the entry system. We want to make it as big
as we can. The limitation with current technology has been the launch
vehicle diameter."
Cheatwood and a team of NASA engineers and technicians have spent the
last three years addressing the technical challenges of materials
withstanding the heat created by atmospheric entry and preparing for
the IRVE-3 flight. The team has studied designs, assessed materials
in laboratories and wind tunnels, and subjected hardware to thermal
and pressure loads beyond what the inflatable spacecraft technology
should face during flight.
This test is a follow on to the successful IRVE-2, which showed an
inflatable heat shield could survive intact after coming through
Earth's atmosphere. IRVE-3 is the same size as IRVE-2, but has a
heavier payload and will be subjected to a much higher reentry heat.
IRVE-3 is part of the Hypersonic Inflatable Aerodynamic Decelerator
(HIAD) Project within the Game Changing Development Program, part of
NASA's Space Technology Program. Langley developed and manages the
IRVE-3 and HIAD projects.
Journalists interested in attending the IRVE-3 launch at NASA's
Wallops Flight Facility should contact Wallops Public Affairs Officer
Keith Koehler at 757-824-1579 or keith.a.koehler@nasa.gov to arrange
for media accreditation.
NASA TV will air the IRVE-3 launch live and stream it on the Web at:
For more information about IRVE-3 and the HIAD Project, visit:
For more information about NASA and agency programs, visit:
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I guess I could put this here as an update of notions:
So, I have the following references on Paraffin Wax, and Nitrous Oxide.
http://www.space.com/23648-new-rocket-e … video.html
http://www.youtube.com/watch?v=DMVgAB_dau4
http://en.wikipedia.org/wiki/Paraffin_wax
http://en.wikipedia.org/wiki/Nitrous_ox … _reactions
http://en.wikipedia.org/wiki/Neutron_radiation
Rocket fuel and Oxydizer (With the option to hard land Paraffin Wax with minimal protection and still have it be useful and retrievable).
Internal engine fuel and Oxydizer (Cars, Tractors, MG Sets (Motor Generator Sets)).
Parafin Wax, other uses:
Radiation Shielding in the case of Paraffin Wax.
Candles a strange thougt, but in a lighting outage for emergencies, perhaps candles could be used in a limited fashion.
Electrical insulator for potted electrical and electronic devices.
Thermostats for process control systems.
Nitrous Oxide:
Medical use for the Nitrous Oxide
Another feature is that it can be solid or liquid form at temperatures reasonably sustainable in the Martian environment (With technological tricks
employed). More managible than Liquid Oxygen for instance.
So, I guess the people that built this:
http://www.space.com/23648-new-rocket-e … video.html
Probablly have all those notions.
As for spacecraft shielding, I would say that your fuel tank for the Paraffin could be a tin can with a flexible bag inside. As you use up the fuel,
you loose some of your shielding, but you create more interior space (Inside the flexible bag) that people can use. The wax would be held between the tin
can walls and the bag.
So a mission could start with a capsule, and a totally filled Paraffin Wax tank, and then on your first burn, that would hollow out, and you could put
your sleeping quarters in it, and move some of your controlls into it. Thereby having more space to use.
Then the insertion burn, would consume much of the balance, and you would either land the capsule to the surface of Mars and have protection there, or
if you had enough fuel you would land the whole thing, depleating your on board supply of Paraffin.
If staying in orbit, you could refill the Paraffin tank from Paraffin blocks put in orbit by a previous supply mission (Such as an electric rocket),
or could refill them from Parraffin blocks hard landed at your intended landing site.
Could you have sent a robot to manufacture Nitrous Oxide from the Martian atmosphere also? I am inclide to think paraffin wax would require a developed industrial base, and could not be done automatically by robot lander.
Last edited by Void (2013-11-21 15:55:57)
I am starting to ask seriously "Why do I do this?"
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This is a very interesting technology. I wonder, what do people think of doing OTRAG as a hybrid rocket with Peroxide/Paraffin instead of Gasoline/Nitric acid? Seems to be an idea with some potential. The net propellant density would be quite high, at 1330 kg/m^3. It might also be simpler to do a hybrid rocket than a liquid one. Maybe it would even be possible to make the modules reusable?
How do you guys think reusability affects the economics of OTRAG?
-Josh
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Well, wasn't the point to bring down the cost by mass manufacture of the units? If you can make them reusable for less than the cost of a new unit, then of course it would make sense to reuse them, but not otherwise.
Use what is abundant and build to last
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Well, that's true. On the one hand, the modules' simplicity pushes me towards the thought that construction will be simple. On the other hand, the tough construction required for hybrid rockets would make reusability and recovery fairly simple.
-Josh
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The main advantages of hydrocarbon-acid are (1) a long history of reliability, and (2) hypergolic ignition. This can still be done with solid hydrocarbon, that being the motor in Spaceship Two.
In small sizes, it is about as easy to to use a heavy pressure tank for the acid and dispense with propellant pumping in favor of direct pressure feed. In larger sizes, the heavier tank becomes too much of an inert weight problem.
The tank will never be light: you have to protect it from being eaten away by the acid. Injector plates are a short-life part for that reason.
Just some practical stuff. I dunno whether hydrogen peroxide is reliably hypergolic with hydrocarbons, liquid or solid. It is with hydrazines.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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Well, OTRAG would certainly be small-sized. I think there are some benefits for Peroxide over Nitric Acid as an oxidizer, since you don't have to worry about NOx (the space industry is going to have to answer to the EPA and the Clean Air Act just about as soon as it really gets going). The densities are also similar. Admittedly, you're switching acidity for higher reactivity, but IMO it's a reasonable trade.
I wonder if you could make it self-pressurizing by dissolving a nonreactive or oxidizing gas (Think O2, N2, Ne, He) in the peroxide and letting it boil out as the pressure decreases, slowing the decline.
-Josh
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An older pressurant scheme is just a solid propellant gas generator. All sorts of weapons used this. Some still do. Maybe not something a colony might manufacture, but certainly something you could easily bring along from Earth on an exploratory mission. Very simple, very reliable.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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That makes a whole lot of sense to me. I was thinking more in the context of Earth launch.
You bring up a very interesting point about Mars launch, though, which is that we need to start thinking about it. I'm gonna make a separate thread.
-Josh
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German company launches candle wax-powered rocket on test flight into space
https://www.reuters.com/science/german- … 024-05-03/
The company, which has 65 employees and was spun off from Germany's space agency DLR, said it already had orders for satellite transportation worth 100 million euros ($105 million).
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Study of the properties and composition of Chinese space kerosene grades
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