Comment by stcredzero | Hacker News Reader

Comment by stcredzero | Hacker News Reader

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So, how would one go about disrupting the world of stealth aircraft? How would one make the whole notion of "Fifth Generation Aircraft" obsolete?

How about Infrared Telescopes operating above the atmosphere? Right now, all fighter aircraft need to burn liquid fuels to extract energy in the form of rapid thermal expansion of gasses, which spew out the back or which operate turbines to run fans.

Large IR telescopes could be used to spot IR sources moving rapidly against the background, which could be localized and targeted by hypervelocity missiles. Stealth planes have a very reduced radar cross section, perhaps the size of a bird, but if you know exactly where the plane is, a radar guided missile could be made to home in on even a bird-sized return in the immediate vicinity.

Such telescopes could be deployed on suborbital rocket planes that can overfly the area on a moment's notice. They could also be placed on circling high altitude drones.

I'd bet that someone at DARPA has already gone through this thought process, and a program to disrupt 5th generation fighters already begun. (Not necessarily with this idea, though.)

Don't think that would be so great in practice.

* The IR part would be vulnerable to countermeasures ( flares etc http://en.wikipedia.org/wiki/File:CH-46_Sea_Knight;_Flares.j... )

* The communication between the telescope and missile would be vulnerable to jamming.

* The communication between the telescope and missile would have to be very fast to make the missile catch up to fast manuring jets.

* If you IR telescopes would be space based they would be more expensive then jets, meaning you probably want have enough of them.

* All high altitude and space based weapon system are very vulnerable to a nuclear weapons. When a nuclear weapons is detonated in low earth orbit there are almost no atmospheric pressure to compress the explosion and little gravity to lower it. Instead the gravity will bend the explosion around the earth, radiating near earth space and high altitudes. Because of this just a single nuclear devise can take out must the world satellites and high altitude airplanes. (This is one of the reason last resort type nuclear weapons don't uses GPS/GLONASS/Galileo satellite navigation. Satellite navigation is amused to be destroyed early in a nuclear war). While a full nuclear war is not very likely, detonating a single nuclear devise like this maybe be more acceptable if attacked.

Fighter jets on the other hand is a proven and efficient weapon against other jets.

    - The IR part would be vulnerable to countermeasures

Yes, but to fool the observer, the decoy would have to travel at the speed of the jets, for as long as the jets. At that point, you might as well have loaded some explosives onboard as well and just have launched a cruise missile.

    - The communication...would be vulnerable to jamming.

Line-of-sight communication by lasers.

    - The communication...would have to be very fast

You picked the straw-man granularity. This is to replace AWACS, not the seeker on the end of the missile. This is to get the seeker on a missile close enough to invalidate stealth.

    - IR telescopes would be ... more expensive than jets

You'd only need one for many fighter aircraft.

    - ...space based weapon system are very vulnerable to a nuclear weapons.

If your air superiority system requires the other side to deploy nukes, then it really seems to me that you've got a winner!

    Fighter jets on the other hand are a proven 
    and efficient weapon against other jets.

Points off for misreading. I never said to replace fighters, period. Radar didn't replace fighters, it just enabled fighters to make intercepts more easily. Disrupting X doesn't mean replacing X.

I agree. In addition to or replacement for AWACS this may work, but you still need to hit the jet with a missile. Detecting is't enough, you also have to stop them.

- Line-of-sight communication by lasers.

I would turn and pull up so the missile must chase me, then deploy my military grade smoke generator :) ( edit: here I am: http://www.dontgivvafuq.com/misc/pics/nam/uh1/uh-1_smokescre... )

    I would turn and pull up so the missile must chase me

Remember I stated a hypervelocity missile. You're assuming a pilot would have enough time to react after the missile has been detected. Still, there's the chance that the missile wouldn't work, so one could still vector fighters in for an intercept. That big smoke plume is going to help my pilots out a lot.

Also, if the incoming airplanes are on a stealth strike mission, their cover has already been blown.

I am convinced now that the disruptive technology for air power is directed energy beams (laser guns). Northrup Grummann have demo'd 25KW lasers the size of large trucks.

Lasers make missiles unnecessary, counter measures impossible and the only hope is to slip through unnoticed.

But working common lasers make almost every area of military activity now a totally different game.

When dad worked there while the ATF-23 program was going, the rumor going arou d the uncleared portions of the facility was that it was going to be armed with a laser, not cannon.

Variants of large scale Passive Radar http://en.wikipedia.org/wiki/Passive_radar was supposed to beat first generation stealth. I suppose it's a closely guarded secret if it still does for the more modern systems. This also disrupts the standard tactics of taking out the radars first to let non stealthy planes follow.

There are also some research around high frequency radar and its ability to overcome stealth.

The SA-3/S-125 Neva soviet surface-to-air missile system are rumored to have something that resembles such a radar. The Yugoslavia army used one to shoot down an Americana first generation stealth fighter in 1999[1]. It may have been the radar, but there are also reports that the bomb-bay doors was opened, raising its radar signature.

High frequency radar are also very vulnerable to clodering. The version that is known to exist can only be used if the plane is flying above the missile battery. If the radar is illuminating the plane in such a way that there is a mountain or other terrain behind it, there will be to much noise to make out the plane. But breakthrough in digital computer based system is expected to change this in the future.

1: http://en.wikipedia.org/wiki/F-117_Nighthawk#Combat_loss

I remember hearing the Russians had a similar satalite IR setup that could actually track our subs in the 1980's, +/- 0.1deg C was claimed.

Surely that was the mcguffin in Roger Moore's The Spy Who Loved Me ?

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