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DARPA's ALASA Could Pave Way For Cheaper, Faster Satellite Launches
hypnosec writes DARPA is all set to take its Airborne Launch Assist Space Access module (ALASA) program to the next level after the program has shown promising results toward its mission of sending 100-pound satellites into low Earth orbit (LEO) for just $1 million per launch."
ALASA is a new program that seeks to streamline production and encourage re-usability and interchangeability in satellite systems.
What does this spell for SpaceX and the Indian effort to send satellites cheaply into space?
Developed by Lockheed Martin and Northrup Grunman who worked on it around the late 1990's-early 2000's? Called the X-33
And most of the bugs were worked out and would give mankind a SSTO (Single State to Orbit) capability without the need to use rocket stages ever again. And spaceplanes would have the ability to take off and land like airplanes.
Musk or someone else could definitely use this technology to revolutionize the space industry.
And not, say, NASA? Somebody explain, please.
In exchange for a lifetime's savings and several months of starvation, you could get yourself a pretty cool way to die.
The government needs to cut back on their military, and deal with the problems of homelessness, poverty, lack of basic health care for millions of Americans, and government corruption.
From your link:
Failures of the 21-meter wingspan, multi-lobe composite material fuel cells during pressure testing ultimately led to its cancellation as a federal program in 2001. Lockheed Martin has conducted unrelated testing, and has had a single success after a string of failures as recently as 2009 using a 2 meter scale model
A 2-meter scale model of a suborbital craft doesn't sound like we're close to SSTO at all.
I don't understand why the idea is being implemented in such a modest manner. The animation has the rocket stage carried aloft for ignition at high altitude by what looks like an F-18. While I don't doubt the performance of the Hornet's engines, wouldn't it make more sense to extend the payload capacity with a larger carrier craft? Say something on the order of the 747-based shuttle carriers? You would be able lift a proportionally larger rocket stage that is able to deliver a more massive payload into LEO or a proportional payload (planetary probe?) even further. It has always felt to me that an airborne launch of a space vehicle has so many more benefits. You are not restricted for being tied down to any one physical terrestrial location. Launches are additionally more versatile due to the more numerous varieties of orbits available at lower costs. Is there a good engineering reason why concepts such as the Soviet-era MAKS was not pursued?
Stay sentient. Don't drink bad milk.
That's great! Oh wait. This is about sending even more spy satellites into orbit cheaply isn't it.
Developed by Lockheed Martin and Northrup Grunman who worked on it around the late 1990's-early 2000's? Called the X-33
The DC-X is a better example, since it doesn't require a runway, it could also be used as a lunar lander and return vehicle. The companies for both got eaten by Boeing.
The single biggest reason is can you see some rich person buying a used one, like John Travolta bought a used 707, and deciding to take a planeload of ceramic coated rebar to orbit and drop it on peoples heads at 22,000 MPH? Cheap access to orbit by private individuals is not in the best interests of those currently in power.
That said, it'd be nice if the owners of the patents on the bell-less rocket nozzle linear aerospike engine would throw their patents open for Armadillo, SpaceX, and the rest; rocket engine bell are *heavy* plus there's the cooling system weight as well.
Your ceramic coated rebar wouldn't go anywhere close to 22000 MPH by the time it reaches the surface. It would probably go slower than a ground fired artillery shell, with less control over its trajectory.
Use it to throw up satellites with a designated lifespan into very low earth orbit and maybe you can have the damn things fall back to earth rather than cluttering up our gravity well...
I wonder what portion of early spacefaring civilizations actually strand themselves on the planet by putting a mess of space junk in their planetary orbits. We're well on our way. There's even shit up there. No, literally--from the early days of the space program. Rumor in the space community is they found some of it by (messy) accident on a later mission.
For the general problem, see http://en.wikipedia.org/wiki/K...
https://twitter.com/peeweeherm...
The single biggest reason is can you see some rich person buying a used one, like John Travolta bought a used 707, and deciding to take a planeload of ceramic coated rebar to orbit and drop it on peoples heads at 22,000 MPH?
Someone could do a lot more damage just by crashing the 707. For that matter, a 1 meter length of #8 rebar is about 4 kilograms, so, at 22,000 MPH would have about 193 MJ of kinetic energy, if it actually reached the ground with the same amount of energy it had before de-orbiting (which would be ridiculous). That's about 8% more than the equivalent mass of gasoline (and, once again, by the time it reaches the surface, it would be a lot less). Of course, gasoline gets to cheat on the energy density factor by using oxygen. You could argue that it's only fair to compare it to something where the energy is entirely self-contained. That's not really valid since the final destination is inside the atmosphere, but we'll give you that one anyway. We'll consider methane, which requires twice its mass in oxygen to combust. That ends up giving it 38.26% of the theoretical maximum of your de-orbiting rebar pieces by mass.
In other words, someone could do a lot more damage just by dropping various sorts of conventional bombs from a 707. Or from a smaller plane for that matter. Or going on foot. Heck, probably just by running around and beating random people with a piece of rebar considering how unlikely it is for the orbitally delivered rebar to both retain significant energy and actually hit a target.
The "rods from god" concept (usually considered with a much larger projectile of the densest practical materials rather than relatively light projectiles prone to tremendous drag like pieces of rebar) is easily shown to be not worthwhile (if you're launching the projectiles from earth with chemical rockets anyway) compared to just about any method of blowing things up. Any physicist or decent engineer with a napkin and a ball point pen can demonstrate it pretty easily. For some reason, the idea keeps coming up.
I had this idea of using ex-military jets and microsatellites and hacked-into ex-military rockets to launch satellites into near Earth orbit in 1995 - based on the proven ttest of the F-15 to airlaunch anti-sallite munitions into orbit. Unfortunately I live in New Zealand, and couldn't find any assistance to investigate my idea. I could have been doing this quite profitably from the mid-90s. But no, Karl Popper was right - New Zealand's not one for research, let alone development ...
Wesley Parish
Waiting for the upper layer daemon paulseaudio for a better design!
Hey, we have all this hardware and software laying idle, why not do a cost reduction exercise and sell the effing thingie in the commercial market?
Seriously tough, I have to wonder if the Chinese, Russians and all the other minions (Iran, North Korea) are not thinking this is a brilliant disguise to be able to deploy an extensive Anti Satellite system.
"If a boss demands loyalty, give him integrity. But if he demands integrity, give him loyalty." (John Boyd, 1927-1997)
There are at least 3 current companies working on a similar concept (air launched small to medium rocket), why are they inventing another when they could buy one of theirs for much cheaper? I can only see two reasons, they want it as a quick response orbital weapons platform and the "small satellite launcher" concept is just an excuse. Number two they're hoping to extract some good old fashioned blank check defense contractor money from the DOD. If its the latter they could have at least put a little more effort into the animation, it looks like one of those bad Sy-Fi channel movie special effects and even the flight profile looks totally unrealistic.
Satellite killers were done this way back in the 1980s - tested, but not deployed. I don't know if the ASM-135 could achieve orbit, but it could certainly intercept something in orbit, and it's the same basic technique. The only thing that would change is the rocket.
Pegasus had at least a dozen successful launches by 1995
If launching satellites from Alaska was a good idea, they would have done this decades ago.
Keep launching them from Florida.
I laughed, then I imagined said person running around hitting people with rebar screaming "RODS FROM GOD! RODS FROM GOD!", and I laughed again.
Aerospike systems are heavier and have more demanding cooling requirements, due to the central plug surrounded on all sides by hot exhaust, with radiative cooling being largely ineffective, and the increase in plumbing to all the injectors. Their advantage is in being less optimized for a particular atmospheric pressure, increased complexity and weight are tradeoffs. This is mainly a large advantage if you're using the same engines for liftoff and for the burn to orbital velocity once outside the atmosphere, which is why aerospikes are common features of SSTO schemes, but it's much less of a benefit if you have a separate booster stage and upper orbital stage or stages. They're not being held up by patents, there simply hasn't been a great deal of interest in developing them for real-world systems (the launch industry as a whole has had little incentive to do anything new for quite a while).
I want to know how John Travolta took a 707 into orbit. Presumably this is a Scientology thing. I thought they used a DC-8.
I'm a good cook. I'm a fantastic eater. - Steven Brust
If you look at what the White Knight (carrier for spaceship 1/2) is, you will see that they are effectively the carrying capacity of a 747 without the weight and drag of the huge body. I fully expect to see them launching satellite payloads from it at some point. In fact, I think I've seen some comments that they are working on that, but at a lower priority than spaceship2
Take a look at the U.K.'s Skylon single stage to orbit spacecraft http://en.m.wikipedia.org/wiki...
The single biggest reason is can you see some rich person buying a used one, like John Travolta bought a used 707, and deciding to take a planeload of ceramic coated rebar to orbit and drop it on peoples heads at 22,000 MPH?
Someone could do a lot more damage just by crashing the 707. For that matter, a 1 meter length of #8 rebar is about 4 kilograms, so, at 22,000 MPH would have about 193 MJ of kinetic energy, if it actually reached the ground with the same amount of energy it had before de-orbiting (which would be ridiculous).
I was being facetious about rebar. Yes, they would be more like shaped tungsten telephone poles with control fins. The numbers I've seen claimed 0.12kt of TNT.
For some reason, the idea keeps coming up.
It'd be quite useful as a "terror weapon or bunker buster".
But assume you're right, and they only drop 1 ton conventional bombs from orbit. Private individuals aren't going to necessarily obey national treaties voluntarily for fear of retribution.
'Rods from God' becomes much more feasible when you imagine space mining enterprise. In the distant future with captured asteroids in earth orbit, obtaining mass already in space and re-purposing it for orbital weaponry is mostly just a math exercise.
Do away with INSURANCE; It'll be cheaper;
Casteism