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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.
And not, say, NASA? Somebody explain, please.
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.
You are aware that mentally ill people and drug addicts are always going to spend whatever cash they are given, and remain homeless, right?
Those are a small minority of poor people. Even regular drug users can manage their lives if the basic needs are fulfilled. If they can't deal with cash, don't give them cash but free housing, food and medication.
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...
> You are aware that mentally ill people and drug addicts are always going to spend whatever cash they are given
You have obviously no clue.
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.
You are aware that mentally ill people and drug addicts are always going to spend whatever cash they are given, and remain homeless, right?
You are aware that you're both mischaracterizing what was said and that you're spouting nonsense, right? The GP didn't say "throw money at mentally ill and drug-addicted homeless people".
Ad you realize that poverty is defined as a certain percentage of the population at the bottom end of the bell curve, right?
Not legally it's not. Economics... life in general, in fact, isn't the kind of zero-sum game you seem to be implying it is. Poverty is defined by a number of guidelines. There are a number of factors. Whether the subject actually has adequate nutrition is an important one. Under those guidelines, 16% of Americans and 20% of American children live in poverty.
And you're aware that basic health care is already fixed, and was before the ACA, sincethe hospitals are legally required to treat you if you present at the ER, right?
What idiot/liar keeps spreading this load of nonsense around? Hospitals are legally required to _stabilize_ you! That means that, if you show up dying of something acute, they have to take you in, but can kick you out the door the moment you're not in critical condition anymore. If you show up, for example, with a terminal case of cancer, they don't have to treat, or even diagnose your cancer. If you have immediate, life-threatening symptoms, they have to provide some treatment for those symptoms. In a practical sense, it pretty much just means that they have to provide a bed for you to die in when you're ready to drop. I'm not sure they're even legally required to provide painkillers for someone dying in excruciating pain. The laws you're talking about are basically just to stop people dropping dead in the ER, and they don't even manage to stop that from happening sometimes.
The problem being that you and those like you that want taxes to pay for free food and housing (& to continue to pay for more of the same when the first houses are trashed) do not pay enough taxes to pay for these programs.
So, you also want everybody else to pay for it.
Democracy is a sheep and two wolves deciding what to have for lunch. Freedom is a well armed sheep contesting the issue
No, I don't want everybody else to pay for it. I want my taxes to be higher so my taxes will pay for it
So you only want to raise your taxes, but leave everybody else's the same ? If so, why don't you just give your money to a homeless person ?
This doesn't make a dent in cost effectiveness of Falcon 9 or PSLV.
Let us calculate per pound LEO costs for these vehicles:
ALASA: $1M / 100 lb = $10,000 / lb
Falcon 9: $61.2M / 28,991 lb = $2,111 / lb
PSLV: $20M / 7170 lb = $2,789 / lb
Tiny satellites at 100lb can easily tag along with bigger launches on these vehicles. Costs may be even cheaper for such secondary payloads or may even free in some cases. If SpaceX succeeds in first stage reuse, or ISRO per chance succeeds in RLV-TD plans, costs may come further down.
So ALASA sounds like a costly option for small satellites today and in future. But the technology as such may have potential if handled by a better managed private company that works on it as a commercial venture.
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.
Setting alarm for 4:30 AM India time...
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.
I laughed, then I imagined said person running around hitting people with rebar screaming "RODS FROM GOD! RODS FROM GOD!", and I laughed again.
Well, partially resusable anyway, and I don't know about a few months - I suspect they'll end up having to successfully land the first stage at least a couple times before they sort out whatever reusability issues are as yet undiscovered. Not to mention the challenge of getting a rocket from a barge in the ocean back to the launch facility without inflicting crippling structural or salt-water related damage - that alone may prove enough of a challenge that actual reusability has to wait until they can get approval to land back on solid ground.
Then again maybe a few guy-wires can keep it balanced on end so it can be brought to shore and transfered by, what, a size large cargo crane? Or maybe a heavy lift helicopter? Hmm. Okay - the F9v1.1 first stage has a dry weight of ~18,000kg, while the massive Mi-26 chopper can carry payloads of up to 20,000kg - just barely enough, with a 500 mile range. That would probably be the easiest way to transport it - avoiding all the complications of transferring it from ship to shore and then overland. Just carry it directly from the landing barge to the launch facility.
So hmm. Could be doable. Provided the ocean is calm enough to let the rocket remain balanced on end long enough for people to get to the barge and get guy wires in place to keep it there.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
You're volunteering to be part of the first wave of reductions I assume?
One must aways remember that economies are artifacts created to serve the people, not the other way around. If the economy becomes counterproductive to the wellbeing of the people, then it should be replaced.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
And why not? The economy exists to serve the people - if it is failing in it's purpose by disproportionately benefiting some while leaving others out in the cold, then it needs to be revised.
Besides, it's not *your* taxes that need to be raised - unless you have a seven-figure income you're one of the people being screwed over by the extreme income inequalities that have infected the US over the last several decades.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Of course this isn't a cost-saving approach, it's real goal is maximum convenience and flexibility. Let's say I want "eyes" on a particular location ASAP, but I don't have any "birds" on a good trajectory for several hours to come. This would allow me to put a satellite precisely on target in under an hour.
And if they can add a miniature projectile launcher into the same 100lb package, they've basically got a global "kill switch" for a limited range of targets. You wouldn't need more than a few pounds of depleted uranium, shaped into a steerable "bolt" and packed with some high explosive, and the necessary thrust could probably be provided by a simple spring mechanism, just like a crossbow.
With a 100lb mass budget, you could probably even allow enough propellant to get the bird back over the same spot (or near enough to shoot at it) on the very next orbit. Say the satellite costs a $mil, plus another $mil for the launch... that's cheaper, per shot, than some of the ordnance already in service. Or, if you don't mind launching two in rapid succession, you can use the first one as spotter and the second one as sniper.
XML is like violence. If it doesn't solve your problem, you're not using enough of it. --AC
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
And if they can add a miniature projectile launcher into the same 100lb package, they've basically got a global "kill switch" for a limited range of targets. You wouldn't need more than a few pounds of depleted uranium, shaped into a steerable "bolt" and packed with some high explosive, and the necessary thrust could probably be provided by a simple spring mechanism, just like a crossbow.
That's not how orbital mechanics work. If you push the "bolt" away, it will just end up in a different orbit, intersecting the original orbit at the point where it was pushed away. To actually deorbit the bolt, you'd need to push it hard enough that the new orbit intersects the Earth's atmosphere. That's a huge push. But even then you have the problem that it's going to hit the atmosphere, and burn up, or in the best case, just tumble erratically through the atmosphere, hopefully hitting the continent you were aiming for.
As the several efforts at Trucking, Air Travel, Insurance, Banking and Financial services deregulation shows
What you get from privatization is higher costs for all but the most profitable segment of the business, monopolism and eventual fraud, deceit and theft.
When there is no hound, the fox will have chicken dinner every night
It all depends on how much delta-V you can impart to your projectile, and by what means (and on what vector). Yes, it's a big push, but you've got 80lbs of reaction mass to work with (at least). It's not hard to imagine making this work with a very simple mechanical device. In particular, if you launch a spotter/sniper pair of satellites, they can both be optimized for their particular jobs.
For example, the spotter-sat could eject a small "hummingbird" reentry vehicle shortly after reaching orbit, in order to descend over the target area, and still be hovering on station a half-hour later when then "sniper-sat" comes into range.
IOW, yes that IS how orbital mechanics work, if you can generate enough delta-v, pointed in the right direction. Once you make interface with the upper atmosphere, you've got the ability to "steer" toward your target.
XML is like violence. If it doesn't solve your problem, you're not using enough of it. --AC
We're not talking about thrust that could be provided by a spring loaded system. You'll need a rocket. And depending on much how thrust you have, you may be waiting another half hour before the projectile starts to be slowed down by the atmosphere. This can be shorter, but then you'll need a bigger push. The next phase will be your few pounds of depleted uranium screaming through the atmosphere at double digit Mach numbers, and burning up in a few seconds. If you do it at night, maybe you can make a nice light show for your enemies.
If you've actually run the numbers, I'm happy to concede the point. but I think it's still an open possibility. And I think the larger point stands: This is all about convenience and flexibility, the ability to get eyes and/or ordnance onto any specific target on the globe in under an hour. If you have a different explanation, please share.
XML is like violence. If it doesn't solve your problem, you're not using enough of it. --AC
Take a look at the U.K.'s Skylon single stage to orbit spacecraft http://en.m.wikipedia.org/wiki...
They eventually plan for the Falcon 9 to refuel on the barge and then fly back to the launch pad. Have rocket, will fly it.
In Soviet Russia the insensitive clod is YOU!
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.
> You are aware that mentally ill people and drug addicts are always going to spend whatever cash they are given
You have obviously no clue.
You obviously have not worked with chronically mentally ill people, nor gone out on an intervention outcall because someone was living in a dumpster because the metal was the only way to shield them, and their perfectly good room at the supported housing facility you had them in before they went off their meds is empty because they decided their room was bugged.
I've worked closely with mentally ill persons as a volunteer (my mother was a psychiatric social worker for a county mental health program, and her specific field was the chronically mentally ill), and still remain friends with some of them to this day, and get them intervention if I know they are in trouble.
Sadly, California county mental health programs are *fricking mean*. I ran into a man having a conversation with his voices, and he has either decompensated or was in the process of decompensating, at the Subway sandwich shop off DeAnza. He wasn't hurting anyone, but when I called Santa Clara County mental health to get someone out to help him, they refused, and said that if he was a problem, I should call the police.
Had I done that, the situation would have been very very bad. What he needed was an intake/intervention person on call to come out and talk him in, and then to see his caseworker, and get back on his meds. He *DIDN'T* need to be 5150'ed, and he surea as HELL didn't need to be dragged off to county lockup by jack-booted Nazis for a couple of days until some asshole too lazy to take a trip out with a deputy in the background for backup could then drag him off and shoot him full of Thorazine for 3 days.
So yes, I kinda *DO* know what I'm talking about. Asshole.
You are aware that mentally ill people and drug addicts are always going to spend whatever cash they are given, and remain homeless, right?
You are aware that you're both mischaracterizing what was said and that you're spouting nonsense, right? The GP didn't say "throw money at mentally ill and drug-addicted homeless people".
No, he said throw money at poverty and homelessness.
You are, of course, free to argue with The National Coalition for the Homeless:
"According to the Substance Abuse and Mental Health Services Administration, 20 to 25% of the homeless population in the United States suffers from some form of severe mental illness."
http://www.nationalhomeless.or...
"Although obtaining an accurate, recent count is difficult, the Substance Abuse and Mental Health Services Administration (2003) estimates, 38% of homeless people were dependent on alcohol and 26% abused other drugs."
http://www.nationalhomeless.or...
I'm not making a value judgement here, and yes, I realize that there is some overlap in those groups, due to the tendency for mentally ill persons to "self medicate" using those drugs available to them. The point is, these problems were nowhere near as prevalent before Governor Ronald Reagan instituted new rules on involuntary commitment in California (as a budget measure), and the NY ACLU won their supreme court case about non compis mentis people being able to refuse treatment for mental health issues. Without treatment, many become homeless.
Ad you realize that poverty is defined as a certain percentage of the population at the bottom end of the bell curve, right?
Not legally it's not. Economics... life in general, in fact, isn't the kind of zero-sum game you seem to be implying it is. Poverty is defined by a number of guidelines. There are a number of factors. Whether the subject actually has adequate nutrition is an important one. Under those guidelines, 16% of Americans and 20% of American children live in poverty.
Poverty is defined politically, and it's whatever's convenient for the politician defining it that day.
It also has a dictionary definition. From that dictionary definition, it's easy to come up with an economic definition.
Look, we've been in Lyndon B. Johnson's "War on Poverty" for 51 years now. You can't win a war if you are unwilling to define victory conditions. We've proven that in the Vietnam conflict, and every war/conflict we've entered since then. When can we stop fighting "The War On Drugs"? When can we stop fighting "The War On Terror"?
What is the F'ing definition of victory conditions in "The War On Poverty"?
If we go by your definition, even a Basic Guaranteed Income can't possibly stop poverty. It's definitionally always going to be with us. We can either accept that it's always going to be with us, and declare at least an armistace, or we can keep throwing money at it with no hope of ever, ever winning, unless we are willing to implement a fully managed economy.
And you're aware that basic health care is already fixed, and was before the ACA, sincethe hospitals are legally required to treat you if you present at the ER, right?
What idiot/liar keeps spreading this load of nonsense around? Hospitals are legally required to _stabilize_ you! That means that, if you show up dying of something acute, they have to take you in, but can kick you out the door the moment you're not in critical condition anymore. If you show up, for example, with a terminal case of cancer, they don't have to treat, or even diagnose your cancer. If you have immediate, life-threatening symptoms, they have to provide some treatment for those symptoms. In a practical sense, it pretty much just means that they have to p
Cool, I hadn't heard that. You're still going to run into regulatory hurdles though - traditionally a far larger challenge than those imposed by physics.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
'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
SpaceX needs to demonstrate a handful of landings on the barge before it can land in terra firma. The primary concern isn't that the stage doesn't crash land, but that it's able to navigate with high precision to the landing spot.
Some launches have large performance margins such that the first stage will perform a boostback burn and land directly at the landing spot (near the launchpad). But in many missions the barge will be needed. The generic number is boostback = 30% performance loss, landing at the barge at the optimal location = 15% performance loss.
The Falcon Heavy has 3 stages, so in many cases the side boosters will RTLS (Return to Launch Site) and the center booster will land on the barge.