F-35 High Energy Laser

spaz wrote: "The biggest obstacle remains the Corona effect. This occurs with power cables charged with extreme voltages at high altitudes. Those conditions mean the air around the cable becomes a conductive plasma, creating the conditions for a dangerous short circuit. Modern aircraft routinely fly at altitudes above 30,000ft where the Corona effect becomes most pronounced. Hybrid electric vehicles will need megawatt powers, meaning they will need to distribute the power from the generator to the motor along cables carrying hundreds of thousands of watts. No solution to the problem yet exists, but lightweight insulation materials may be promising."

Maybe they discovered the needed cable insulation for the Corona Effect at the University of Melbourne, a ceramic based cable insulator that is heat and fire resistant.

Electrical Cable Triggers Lightweight, Fire-Resistant Cladding Discovery
Tue, 11/20/2018 - 10:40am
by University of Melbourne

A University of Melbourne researcher has led the successful development of an organic, non-combustible and lightweight cladding core - a product that was previously thought to be impossible to create.

Typically, lightweight cladding is made from organic, carbon-based, composite materials like plastic, but these materials by their nature are combustible. Non-combustible materials like steel, ceramic tiles or concrete are much heavier and more expensive to produce and install.

University of Melbourne Fire Engineering Group research leader Kate Nguyen has discovered that the plastic insulation around electrical cables uses tiny ceramic particles that activate and chemically interact with each other, forming and spreading a heat resistant network through the material.

...The biggest obstacle remains the Corona effect. This occurs with power cables charged with extreme voltages at high altitudes. Those conditions mean the air around the cable becomes a conductive plasma, creating the conditions for a dangerous short circuit. Modern aircraft routinely fly at altitudes above 30,000ft where the Corona effect becomes most pronounced. Hybrid electric vehicles will need megawatt powers, meaning they will need to distribute the power from the generator to the motor along cables carrying hundreds of thousands of watts. No solution to the problem yet exists, but lightweight insulation materials may be promising."

Wouldn't something like a shielded cable work?

This Corona effect has always been an issue for radars. That is why they run in sealed pressure controlled boxes.

I suspect they will do the same with tactical laser weapon pods for fighters. They can have enough batteries/capacitors in the sealed pod to to fire it a few times, and then recharge it over time with lower voltage/power from the aircraft.

The "Killacycle" electric drag racing bike got 500+ HP out of a ~200lb lithium battery pack. 500 HP is ~373kw, so that should be good for a ~150kw laser assuming <50% efficiency, and at 9.7kwh of capacity, it would in theory be able to fire the laser for ~90 seconds. It may even be preferable to avoid the complexity of recharging in flight and just put enough battery in the pod to last an entire sortie.

The "Killacycle" electric drag racing bike got 500+ HP out of a ~200lb lithium battery pack. 500 HP is ~373kw, so that should be good for a ~150kw laser assuming <50% efficiency, and at 9.7kwh of capacity, it would in theory be able to fire the laser for ~90 seconds. It may even be preferable to avoid the complexity of recharging in flight and just put enough battery in the pod to last an entire sortie.

Don't forget cooling; the energy that isn't going into the laser shot is almost entirely waste heat, which has to be dealt with somehow.
That will likely be some sort of active cooling system; if the laser is an isolated pod, that will cut into the power available for the laser.

Why DARPA thinks air assets will be the last to get laser weapons

By: Aaron Mehta

Dec 20, 2018

WASHINGTON – It’s been a running joke inside the defense technology community for years: lasers are the weapons of the future ... and always will be. But while experts have long predicted laser systems, also known as directed energy weapons, are juuuust over the horizon, more and more technology experts have said they believe lasers are truly in the realm of the possible in the near-term for the Pentagon. Which raises the question: who gets them first?

Speaking at the Washington Post earlier this month, Steven Walker, director of the Defense Advanced Research Projects Agency, said, if possible, the Air Force would love to get directed energy up and running tomorrow. "I never met a four-star general who didn’t want a laser on his airplane,” Walker said. “It would be really neat. That would be a really neat technology and capability.” But weight remains an issue, Walker warned. Quite simply, the technologies needed to support a laser weapon are heavy. “All this power generation and cooling adds up in terms of weight," he said. As a result, “I think airplanes will probably be the last, sort of, application of it, but I think we’re very close to having a ship-based capability,” he said. “The Navy’s done some demonstrations in that space. I think ground capability, lasers from the ground, from trucks, are being worked pretty heavily. And those will be closer than a laser on the airplane.”

https://www.c4isrnet.com/electronic-war ... r-weapons/

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This does not mean you can't initially put four smaller and lighter lasers on to a flight of four fighters, and have them surround and mutually attack the same target at the same time, coordinated via data-fusion pointing, timing and coop-engagement.

That makes sense.

I think USAF will be the last of the three major branches to have a combat laser deployed, and when they do the first platform won't be on a fighter it'll be an AC-130. Seems they are always fiddling around with the weapon load of AC-130s and JSOC is often a bit quicker to adapt and try new things. AC-130 seems like a natural platform since it can handle the weight, operates at lower altitudes, and is definitely something that could make use of unlimited magazine that comes with DEWs.

That makes sense.

I think USAF will be the last of the three major branches to have a combat laser deployed, and when they do the first platform won't be on a fighter it'll be an AC-130. Seems they are always fiddling around with the weapon load of AC-130s and JSOC is often a bit quicker to adapt and try new things. AC-130 seems like a natural platform since it can handle the weight, operates at lower altitudes, and is definitely something that could make use of unlimited magazine that comes with DEWs.

A heavy experimental DEW has already been installed and tested in the weapon bay of an Avenger drone. No particular need to get humans that close. In fact you could put a similar system into the bay of an MQ-25 Stingray.

Current undersecretary of defense R&D doesn't think airborne lasers will be effective.

https://www.defensenews.com/2020/05/20/ ... e-defense/

Noting however that he's talking specifically about their effectiveness as ballistic missile defense systems; he's not commenting on their use for self-defense, close-in air-to-air combat, counter-UAS, etc.

Is a practical laser system EVER going to be a reality o. An F-35?

https://breakingdefense.com/2020/12/gen ... ed-lasers/

The article here mentions some nice innovations.
But what happened to the dream of removing the lift fan, and having the engine transaxle set up power the laser?

Was the dream just that?

I read through that entire BrakingDaFence article... only to read nothing new. Freedberg baits the reader in with tales of breakthroughs that General Atomics has made to create a laser small enough to fit in a C-130J. Now maybe GA has done some really good engineering to scale things down and save weight, decrease cooling requirements... but I read about distributed slab lasers several years ago. So I'm still scratching me hedd awunderin where is this technological magic marvel breakthough Freedberg dangled in front of my eyes?

But at 250" long, I do not see this 250KW lazer fitting in an F-35 anytime soon.

I am still waiting for LM to announce a 100KW laser (or more powerful) for an F-35. One article I read about the LM fibrerlaser technology stated that the longer the individual fiber, the more optical gain... BUT that the fibers can be looped, wound in a helix etc... So LM could conceivably wind all the laser fibers around the periphery of an internal weps bay from what I understand.

Also, recent posts have shown the F-35 produces more power than any other tactical aircraft right now. Upwards of 400KW(!?!) It may not be necessary to replace the Bee's lift fan with a laser module connected to the -600 motor via a driveshaft -- all Panthers may already generate the necessary power. Also, the amount of electrical power produced by a -600 driveshaft is probably in the megawatts, and would pose a tremendous cooling problem.

Much ado about not very much, I'm afraid...

After some further reading, I should say the latest Freedberg BrakingDaFence article is much ado about some contracts announced a year or more ago. For the curious reader, I found these two articles to be more interesting about the current state-of-the-art for laser weapons:

EXCLUSIVE Killing Cruise Missiles: Pentagon To Test Rival Lasers

Lockheed Launches Laser Production Line; Bets On Fiber Tech

The article indicates size, weight, scalability, thermal stability, beam-combining, high-power level and precision-dwell are largely solved and good enough for an airborne laser weapon.

Probably not for retrofit to F-35s but look how far things have come in the past decade alone.

Certainly this can be integrated into aircraft at this point though. The article talks about two known airborne laser efforts, one for the Lockheed C-130, and another for an undisclosed Boeing aircraft. What are the chances GA aren't doing the same, or planning to?

The article also mentions two other competitors to GA in producing he 300 kilowatt prototypes for follow-on programs from there for services to select as the basis for a weapon.

The companies are clear the next fighter will require a high-energy compact low-weight laser, in the 300 kilowatt range, and they need to turn their best technology into a weapon. GA just seem to have the best for now to produce a practical weapon in the air. So I'm not so pessimistic.

Bottom line is, does F-35 require a HEL to win the next major war? No. Would be nice, but not necessary.

Does F-35 require a high output tactical DIRCM to win the next major war? Probably no, but it can definitely preserve a lot of aircraft and pilots if it has one and dramatically expands the tactical possibilities and the ability to fight the aircraft. Plus advanced DIRCM technology can be applied to everything in the air for very positive defensive affect thereafter.

Walk before you run.

A scalable high-powered DIRCM can evolve into multirole effectiveness. Which then leads to a scalable effective HEL attack weapon on the next generation of strikefighters, which are specifically designed for it, i.e. 6th-gens have a HEL design optimization and integration, a short engagement cycle, and practically unlimited ammo, rate of fire limited by thermal dissipation.

So stealth becomes even more critical, see-first and fire-first as well, sensors and beams must have maximum performance in variable WX. Materials that provide both signature reduction plus laser energy resistance and energy dissipation too. An emphasis on autonomous unmanned aircraft (evolution of a Loyal Wingman) with higher range and auto drone AAR continuous loiter performance out front. Comms networks which can't be jammed, to maintain unmanned and autonomous data flow from these to the manned aircraft.

It all looks to be viable and within reach.