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Airborne Launch Assist Space Access


Francesco

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DARPA has loaded this video on their Youtube channel:

It's an air launched rocket intended to put small (100 lbs) payloads to low earth orbit for 1 million $ per launch.

Interestingly, the video shows the rocket as having two stages, while the wiki page

http://en.wikipedia.org/wiki/Airborne_Launch_Assist_Space_Access

reports that there's gonna be only one set of engines, using detachable fuel tank(s) to shed weight.

This is akin to Russian Briz-M's jettisonable fuel tank, I guess.

(And to KSP crafts, yo.)

My question is, what can be done with such a small payload?

Military crafts, observation satellites?

Also, small sats funded by universities, if DARPA wants to share the technology.

In fact, does someone know what is the usual cost for a piggyback ride on a bigger launcher for micro/nano sats?

And what is the rationale behind having a system ready to launch in 24 hours?

Aren't bigger satellites already surveilling every square inch of Earth?

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And what is the rationale behind having a system ready to launch in 24 hours?

Aren't bigger satellites already surveilling every square inch of Earth?

Yes, and in much higher fidelity than you'd get from a 100lb minisat.

I may be getting old and cynical - but my first thought was "That's a great way of funding ASAT weaponry without calling it a missile". 100lb of ball bearings launched in an opposing orbit to your target is gonna pack a tremendous amount of kinetic energy.

edit: broke out the notepad for random laughs - 100lb of ball bearings launched in a westward equatorial orbit would hit something coming the other way with just under 5.2 gigajoules of energy. Slightly more than strapping a tonne of TNT to your target, lighting the fuse and running away giggling.

Edited by Tarrow
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The problem with using recon sats is that everybody knows when they'll be overhead. They're easy to dodge and spoof.

Putting a recon sat in orbit on short notice can can catch an opponent off guard, allowing you to catch activity you otherwise wouldn't.

That's enough reason for the Air Force to move ahead with this proposal.

Best,

-Slashy

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There's nothing really special about this, Orbital Sciences has been doing this since 1990, In the form of the Pegasus http://en.wikipedia.org/wiki/Pegasus%28rocket%29 , http://imgur.com/a/Ne8xJ , and there have been several proposals for it throuout the years http://en.wikipedia.org/wiki/Air_launch_to_orbit

The advantage of this system is in the low cost, and in the fact that it uses an already existing plane (F-15) without any modifications at all, instead of big, expensive carriers.

ALASA would use the Eagle's weapon communication bus, so the plane wouldn't need to be repurposed for the role of air launch.

The problem with using recon sats is that everybody knows when they'll be overhead. They're easy to dodge and spoof.

Putting a recon sat in orbit on short notice can can catch an opponent off guard, allowing you to catch activity you otherwise wouldn't.

That's enough reason for the Air Force to move ahead with this proposal.

Ah, I see. Thanks!

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Yes, and in much higher fidelity than you'd get from a 100lb minisat.

I may be getting old and cynical - but my first thought was "That's a great way of funding ASAT weaponry without calling it a missile". 100lb of ball bearings launched in an opposing orbit to your target is gonna pack a tremendous amount of kinetic energy.

edit: broke out the notepad for random laughs - 100lb of ball bearings launched in a westward equatorial orbit would hit something coming the other way with just under 5.2 gigajoules of energy. Slightly more than strapping a tonne of TNT to your target, lighting the fuse and running away giggling.

You would want to launch in an suborbital trajectory, no need to reach orbit so you don't leave the ball bearings and can carry more of them.

Such an system existed, currently the US has the SM2 missile who had hit one satellite, its primarily an ABM missile.

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And what is the rationale behind having a system ready to launch in 24 hours?

Aren't bigger satellites already surveilling every square inch of Earth?

Bigger sats are in fixed orbits. The high inclination ones can cover every inch of the Earth, but they can only pass over a specific spot for a few minutes every 3 or 4 days. If you are planning an operation that you want to monitor closely for several hours or at a specific time, this can be a problem. The only way around this is to use recon drones, but that means that you might be violating airspace of a foreign country, which can be considered a hostile act with its own set of diplomatic problems.

In addition, the orbits of military satellites are well known (and even published on astronomy websites such as www.heavens-above.com), so the bad guys know exactly when to hide their stuff.

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Don't the Chinese have functional ASAT technology?

Perhaps it's taking a "liberty ship" approach to things in the event of a conflict. If you are able to launch more surveillance satellites quicker and more cheaply than your enemy is able to destroy them, you have the advantage.

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And what is the rationale behind having a system ready to launch in 24 hours?

Aren't bigger satellites already surveilling every square inch of Earth?

Why do you need platoon/company/battallion level support weapons, when there is heavy artillery and air forces available? Because they're tactical assets that are available on short notice at your command, without having a higher-up allocate strategic assets for your use.

If there's going to be battle tomorrow, you can launch 50 off-the-shelf satellites to give you real-time surveilance information on the battlefield for the duration of the battle. When the battle is over, you can just let the orbits of the satellites degrade, because they're so cheap there'se no point in spending resources to track them.

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  • 4 months later...
Yes, and in much higher fidelity than you'd get from a 100lb minisat.

I may be getting old and cynical - but my first thought was "That's a great way of funding ASAT weaponry without calling it a missile". 100lb of ball bearings launched in an opposing orbit to your target is gonna pack a tremendous amount of kinetic energy.

edit: broke out the notepad for random laughs - 100lb of ball bearings launched in a westward equatorial orbit would hit something coming the other way with just under 5.2 gigajoules of energy. Slightly more than strapping a tonne of TNT to your target, lighting the fuse and running away giggling.

Why should you do that, the standard missile 3 fits in the vertical launcher on an warship and can intercept low orbit satellites going ballistic, where is no reason to go into orbit at all if you can target well and aegis cruisers can.

Yes using an jet as first stage you should be able to get up to medium attitude orbits if you just go ballistic.

More probably this is an way to launch the small satellite low orbit communication networks. Main benefit of using an fighter rater than an large jet is that you can take it higher before releasing as air resistance is far more of an problem for an small rocket.

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Perhaps it's taking a "liberty ship" approach to things in the event of a conflict. If you are able to launch more surveillance satellites quicker and more cheaply than your enemy is able to destroy them, you have the advantage.

That would risk triggering a Kessler cascade, after which nobody has anything in LEO.

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That would risk triggering a Kessler cascade, after which nobody has anything in LEO.

Orbits low enough to be reachable by this kind of system are going to be too low to contribute to long term debris issues. This concept is essentially what the chinese already have with the Kuaizhou system.

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  • 5 months later...

http://spacenews.com/darpa-airborne-launcher-effort-falters/

ALASA in it's current form has been cancelled due to explosions in handling tests of the new fuel; it's now considered too unsafe to be attached to a crewed aircraft. DARPA and Boeing are working to apply the technology to ground-launched vehicles.

Edited by Kryten
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They are using thw wrong platform, the F22 has high thrust to mass ratio, which means it can gain velocity on the ascent, release and and stick backwards allowing the rocket to fire remotely.  The fuel issue is a petty issue IMHO. 

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On Mon Feb 09 2015 14:53:55 GMT-0800, Francesco said:

DARPA has loaded this video on their Youtube channel:

 

 

It's an air launched rocket intended to put small (100 lbs) payloads to low earth orbit for 1 million $ per launch.

Interestingly, the video shows the rocket as having two stages, while the wiki page

http://en.wikipedia.org/wiki/Airborne_Launch_Assist_Space_Access

reports that there's gonna be only one set of engines, using detachable fuel tank(s) to shed weight.

This is akin to Russian Briz-M's jettisonable fuel tank, I guess.

(And to KSP crafts, yo.)

My question is, what can be done with such a small payload?

Military crafts, observation satellites?

Also, small sats funded by universities, if DARPA wants to share the technology.

In fact, does someone know what is the usual cost for a piggyback ride on a bigger launcher for micro/nano sats?

And what is the rationale behind having a system ready to launch in 24 hours?

Aren't bigger satellites already surveilling every square inch of Earth?

A better question would be what the point of this would be. Minotaur and SPARK can do everything this seems to be capable of doing- but with somewhat greater payload that allows for more cubes at to be launched.

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