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Laser Cannons Coming to an F-16 Near You
dxprog writes "Reuters is reporting that the US Pentagon is designing a laser cannon that's small enough to fit onto a fighter jet yet powerful enough to knock out a missile. "The High Energy Laser Area Defense System (HELLADS), being designed by the Pentagon's central research and development agency, will weigh just 750 kg (1,650 lb) and measures the size of a large fridge." Now all we need to do is make fighter jets space worthy for that true Star Wars feel."
F-16 operating ceiling = 15.240 kilometers
Minimum LEO satellite altitude = about 150 kilometers
I couldn't find any information about the range of the HELLADS system; that information is probably classified. However, TFA claims there will be a 150 kilowatt version of the laser by 2007. Any laser experts know if that power of laser can take out a target 135 kilometers away? Is the idea even feasible?
"The advanced societies of the future will be driven by competing systems of psychopathology." -JG Ballard
To quote a friend from the Israeli army that is sort-of relevant:
"M16's are not designed to kill, they are designed to maim, because a wounder soldier is more of a liability to the enemy than a dead one."
But we still use M16s... odd... (well, WE use M2's or something like that)
https://www.accountkiller.com/removal-requested
For all of the people who criticize your "mirrors" proposal: ablatives.
You can even combine defensive concepts. Missiles being relatively small, relatively mass produced items, processes that normally cost a lot can be proportionally cheap compared to the cost of the guidance systems, propulsion system, and handling costs. So, for a multipart defensive system:
* A "shiny" ablative system on the nosecap and leading edge fins - perhaps something as simple as silicon-impregnated cork mixed with aluminum, silver, or gold (better at IR) powder.
* The nosecap and leading-edge fins made of silvered (again, with a good visible/IR reflecting material) RCC (again, since they're small and the process to make them can be automated, the costs shouldn't unreasonable). RCC can take extreme temperatures without becoming ductile.
* Other parts of the body made out of unpainted, shiny aluminum or a silvered surface.
It's less extreme than other defensive mechanisms used for various kinds missiles - MIRVed warheads, anti-ship missiles that hug the water and then take a sharp climb and descent, etc. And it's certainly simpler than many of the counter-countermeasure methods used by modern missiles.
Are there any deer in the theater tonight? Get 'em up against the wall.
150 kilowatts is 201 horsepower. (conversion link; 1 horsepower = approximately 745.7 watts)
F-16 Aircraft use a powerplant ranging from 15,000 to 19,000 (28,000 to 32,000 with afterburner) pounds force of thrust.
To convert between thrust and horsepower, use this formula: [(Thrust in lbs x Speed in mph) / 550] x 1.47 = horsepower (formula link)
So let's assume an airspeed of 400 miles per hour.
Without afterburners:
Low: ((15,000 * 400) / 550) * 1.47 = 16,036.3636
High: ((19,000 * 400) / 550) * 1.47 = 20,312.7273
And with afterburners:
Low: ((28,000 * 400) / 550) * 1.47 = 29,934.5455
High: ((32,000 * 400) / 550) * 1.47 = 34,210.9091
So let's say about 18,000 horsepower on average regularly and 32,000 horsepower on average with afterburners.
A 150 kilowatt laser requires 1.1% of the total engine power produced (on average) by an F-16 turbofan engine, and 0.6% of the engine's power with afterburners engaged.
In other words, I think they've got all the power they need.
Reinvent the wheel only at either a lower cost, greater effectiveness, or your own personal enrichment and satisfaction.
All this has been thought through in the 80's, when SDI was being developed. The amount of energy directed onto one spot is so intense it will burn through anything less than a polished mirror. Some people used to think that making ICBM's reflective, or twirl in flight, would solve things...but it's kind of like pirouetting in front of a 50 caliber rifle. These lasers are nothing to mess around with, they're thousands of watts projected onto a very small spot. The thermal shock alone is mind-numbing.