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Blimps... In... Space...
LandGator writes "MSNBC reports a California company with an alternate launch site in Texas, JP Aerospace, is on their third test of a blimp system specifically designed to fly to space. Blimps. To Space. At payload costs around a dollar a ton to LEO. Their concept, first unveiled at the Space Access '04 conference in Phoenix last month (with a blog report here, include the Ascender, a ground-to-near-space blimp, which docks to a helium-inflated two-mile-long station at the edge of space, over 20 miles up. Another ship, also a blimp but specifically designed to reach orbit, takes the payload from there to LEO, using well-proven electric propulsion (AKA 'ion drive'). That trip to LEO would take up to nine days, but that's a good thing; for, what goes up fast, must come down fast, and speed is energy which must be bled off by either massive amounts of expensive and explosive rocket fuel, or through ablative heat transfer which has its own problems (as we have seen before). JP Aerospace has flown many PongSats -- micropayloads the size of a ping-pong ball -- for balloon or rocket-launch. Over 1,500 PongSats have flown to date, which demonstrates a track record in near-space few of the X-Prize contenders can approach. Oh, yes, the Air Force is interested."
Well, if they can truly get cargo to space at a single US dollar/ton, this is orders of magnitude cheaper than current costs which run approx $10k/kg. Which could very well result in a total destabilization of the space launch business. (a little chaos now and then is a good thing.....yes?). Of course we also have maglev and space elevators which could also provide this a run for the money, but I suspect maglev would be more expensive and due to helium costs, space elevators might be cheaper still.
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What's even more amazing is they have only been around since 2002. Going from start-up company to your 3rd test flight in that amount of time is.. well.. impressive.
Hmmm.
Eh? That's the coolest thing I've seen in a while, if it's at all possible. Kinda blows the x-prize away.
Quid festinatio swallonis est aetherfuga inonusti?
Africus aut Europaeus?
on their third test of a blimp system specifically designed to fly to space
"Now, the object of this expedition is to see if we can find any traces of last year's expedition."
I watched C-beams glitter in the dark near the Tannhauser gate.
Incase there are actually people not reading the linked article, the interesting part is quoted here:
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I would love to see huge balloon animals in the night sky..
Or maybe I'm the only person who remembers F-troop. Seriously, this is going to be a bit weird, because at that size, it's going to be quite visible all the way up, even in orbit.
Am I part of the core demographic for Swedish Fish?
Second, LEO isn't just *up*, it's also speed that keeps you falling back to earth. That kills the up-fast-down-fast idea. Are these space blimps (inflatible tech! Dr. Schlock would be proud) going to manage to accelerate a load from a relative standstill to LEO speeds using an ion engine (which has very weak acceleration) in just a few days? Unless I'm missing something, that doesn't seem very likely.
That aside: Cool idea. This sort of infrastructure wouldn't be as awesome as a space elevator would be, but it sure seems a hell of a lot more likely (cheaper, safer, possible without huge leaps in materials, etc). Once you're moving tons of material to orbit for a very small price (costs more to ship something across the ocean!), it seems like space exploration is ready to take off (no pun inte... oh, who am I kidding?) in a very real way.
Every year during my review, I just pray the words "slashdot.org" aren't mentioned.
I can't way until they offer nine day cruises to near-space.
Imagine the view...
Seriously, this is a good stepping stone to space tourism.
Low Earth Orbit.
This is neat, but too bad it wouldn't work for the X Prize. If it takes 9 days to get up there, then comes back slowly too, they wouldn't be able to relaunch the same craft in time. That's a shame, as this sound promising and could really use the extra funding from the prize itself and that the prize's notoriety would help it get.
Hopefully this solution will be developed and used commonly when fats times to orbit aren't a must.
It's like a Sagittarius, only friskier.
So the first word visiting aliens will see will be "Goodyear."
The coolest voice ever.
I'm sure they have thought this out, but:
Can you really accelerate a big inflated condom to escape velocity with an ion drive? I mean, it can only get so high on He, and I'm assuming that at its apogee there will still be an appreciable amount of atmosphere. Would an ion drive be able to overcome the drag force? Anyone willing to do the math?
The Hindenburg was filled with hydrogen, not helium. Hydrogen burns, helium does not. Besides, the Hindenburg was painted with some rather flammable compounds..
That trip to LEO would take up to nine days, but that's a good thing; for, what goes up fast, must come down fast
What goes up fast must come down fast? Unless I'm missing something, low earth orbit still means going several thousand miles an hour. The rate you ascend at has nothing to do with how quickly you'd come down at.
AccountKiller
Whether you reach orbital velocity in 9 days or 9 minutes, you're still travelling at orbital velocity.
Pong statistics for leo.space.com:
Balls: Sent = 2002, Received = 1001, Lost = 1001 (50% loss)
Striving to be common
Striving to be common...
Hydrogen is half the density of Helium, not 1/4. And it wouldn't give anything like twice the buoyancy, either. If you're confused as to why this should be so, I recommend doing a little web research on the following terms: "monatomic gas", "chemical mole", "ideal gas law". "density of air".
-Mark
That is what the ion engine is for. They calculate it will take 9 days to acclerate the craft to 8km/s.
People have a misconception that if you put a hole in a blimp, that it crashes. If properly designed it will not.
It all comes down to the pressure difference between the insides and the outsides of the blimp.
Reading their promotional literature, they do not maintain much of a pressure difference between the insides of the blimp and the outsides. Thus, a hole will not really result in the helium being replaced with the heavier atmospheric gases.
Most blimps can manage a safe emergency landing if even significantly damaged.
Last but not least, I suspect that their choice of helium was more due to the dramatic reduction in safety precautions they have to take with the stuff on the ground. There are real advantages to using diatomic gases over monotomic gases (for example, they leak much more slowly through micro-pores). But the advantages do not make up for the disadvantage of the risk of explosion on the ground or at low altitudes.
http://www.jpaerospace.com/atohandout.pdf
Here are the details:
Atmospheric airship with crew of three takes payload to 140,000 ft. Airship uses lift and buoyancy, and driven by propellers designed to operate in near vacuum.
Dark Sky Station (DSS) at 140,000 ft. Permanent, crewed facility.
Airship that flies from DSS to orbit. Over a mile long. Uses buoyancy to climb to 200,000 ft. From there uses solar/electric propulsion to reach orbital velocity over several days.
Continuing to use solar/electic propulsion, it can keep on going to anywhere in the solar system.
Several "DSS" platforms have been flown. All equipment has been flown at 100,000 ft. and tested in the environment. Ion engine tests of the orbital airship at 120,000 ft. will occur in the next five months.
Every segment of the plan has funding. DoD is funding the atmospheric airship for reconnaissance. Telecom companies are funding DSS.
Hindenburg, anyone?
Man, I'd hate to be in the blimp industry. Give a dog a bad name, or what? One big accident almost seventy years ago and every time somebody suggests a blimp as a solution to anything, everybody assumes it's a fiery disaster waiting to happen. It's as if we'd all given up on ships after the Titanic.
Please donate your spare CPU cycles to help fight cancer and other diseases
If enough money is put into the project, we can start space industrialization in a year or three, we don't have to wait until we find out if the space elevator is actually possible, we don't have to build giant rail guns for cheap space launches if the Elevator is unworkable.
It's time to start work on actually building Space Power Satellites at the "proof of concept" level. For more info, click here
Tech Public Policy stuff
The blimp in Stephenson's The Diamond Age was filled with vacuum, and a cyberpunk author did something similar with tall buildings in one of his books (building tops were large balloons whose lift helped support the building weight so the thing could carry more floors).
This is different than a gasbag put into a vacuum. Stephenson's blimps were under compression, and the proposed blimp-in-space is under tension.
Compression's a bitch. Holding a 500-foot-dia sphere in enough equalized compression to avoid buckling and collapse is insanely difficult, which is why nanotech was the narrative used to justify it. But tension? Ha, tension's a walk in the park particularly for materials formed into skins.
Just eyeballing it, we have more than enough common materials like mylar that can produce a gasbag of sufficient size (i.e. common Goodyear blimp). If the tension proves too much for mylar, then some strenghtening can be done like sail makers do all the time, with carbon-fiber thread wrappings, etc. But my rule-of-thumb gets hazy for things that are kilometers in size under the gas pressures they must contain, since tension rises appreciably with the radius of curvature.
[You have a stable society when some nut guns down a schoolyard and the law doesn't change.]
Actually it is. Any Nuclear reactor can be tuned to produce Helium. I think they did this briefly at the Laurence Livermoor reactor for a short time before decomissioning it.
"Curiosity killed the cat, but for a while I was a suspect."- Steven Wright
This is stupid, I swear noone has any vision.
First, they're talking about 20 miles up for this two-mile 'lily-pad'. At 20 miles, we still have atmosphere, so we still have buoyant(sp) forces acting. Since there's a buyoant(sp) force at work, orbital mechanics can be damned. Your airship doesn't fall back to Earth because it's lighter than air.
Are you with me, then? You have a lovely two-mile long launch platform. From here, you launch another, smaller balloon with even less density and a few ion engines. This smaller balloon floats up as high as the remaining atmosphere allows. At this point, we'll say that the balloon is 'floating' on the very top of the Earth's atmosphere. It won't go down (buyoant[sp] force) and it won't go up (gravity). At this point, as long as the ion engines can beat the force of gravity, you have acceleration.
Acceleration, even small amounts of it, mean a lot in a vaccum. Give it a couple weeks and you'll find yourself speeding along at 8 km/s. Let go of the object you want in orbit and use the same ion engines to slow down. Physics being what they are, you should wind up back where you started with the same amount of velocity as when you left. At which point, you'll be 'floating' on the top of the Earth's atmosphere and you can manipulate your airship to get back down to the 20-mile-high 'lily-pad'.
Figure a fully outfitted luxury passenger module, including oxygen and other facilities, is ten tons per passenger.
That's $200 per passenger to get to the "edge of space", or $9000 per passenger for low earth orbit.
Space cruises for civilians now become feasible.
Pretty exciting.
Finding God in a Dog
This blimp needs air for bouyant lift, so you are inevitably going to be in the atmosphere. Ion engines, unfortunately, only work in a vacuum. And even if they did work at that altitude, the drag would so high that they wouldn't accelerate the ship at all.
.01, then the drag force at 5000 fps, 1/5 of orbital velocity, is: .5 rho Cd V^2 A
.01
If the ship was, say, 50 ft wide and had a rediculously low drag coefficient of
where
rho is density (about 1.7x10^-5 slugs/ft^3)
Cd is
V^2 is velocity squared. At 5000 fps, that's 2.5x10^7
A is area, 50 ft
This yeilds a drag of a little more than 100 lbf.
The most powerful ion engine is Nasa's new HiPEP that has a thrust of about 1/10th of a pound.
Now, I'm a big fan of JP Aerospace, and wish them all the luck in the world. Their program of launching sounding rockets from high-altitude balloon platforms was quite exciting. Hypersonic blimps, though, are just not going to happen.
Thad
I love Mondays. On a Monday, anything is possible.
I came up with a similar result. Maybe we should just shut up and short the stock later on. :)
Does the name Tacoma Narrows ring a bell?
Yes, it does. And it did to the people who looked at the space elevator as well. The Tacoma Narrows bridge fell because the period of its resonant frequency happened to be close to a naturally occurring oscillation.
In order for resonance to be a serious problem, the induced oscillation has to occur over the entire object, and it has to be close in period to the natural frequency of the object.
The fundamental period of the space elevator is 7 hours. There's nothing which occurs on the full scale of the elevator (hundreds of thousands of kilometers) which is near to 7 hours.
So induced oscillations aren't a worry.
(Wind oscillations are a non issue if they don't rip the ribbon. The ribbon is huge. The atmosphere is just a tiny sliver compared to its full length.)
Yes, I know you won't get aerodynamic lift without air, so there will be some drag, but your back-of-envelope calculation doesn't tell enough of the story to know if it's a showstopper.
My question is how the heat gets dumped on the way back. I guess it has so much surface are the heat load at any given point is small, but we're not talking about titanium here.
I don't know if anyone has noticed this, but at the "dark sky station" stationed at 100,000 feet up, since the station is floating rather than orbiting, there is no issue with zero gravity. Weightlessness is caused by the fact that an object in orbit is "falling" to the earth--and missing. But the "dark sky station" is not in free-fall; it's held aloft via bouyancy, and so workers on the "dark sky station" will experience full gravity. No problems with muscle atrophy.
Furthermore, it's not like poeple haven't flown up to 100,000 feet up in balloons; what becomes technically interesting is building a permanent or semi-permanent station as a balloon at that altitude.
The best part is that the worlds record for the highest skydive is above that altitude. So theoretically in the case of a catestrophic emergency, people could simply get into their skydiving space suits, and jump.