NerdGuy #18: Bad Guys Need Good Weapons

The HEL-A laser.

Nope, not a Hell-uv-a laser, though it is one. Rather a High-energy Laser (Airborne). A weapon that I unleashed in my latest novel, Ghostrider. (I couldn’t be sure that HEL-A is the weapon’s real name, I only found one passing reference on that. But since it’s deeply shrouded in secrecy, I’m sticking to it.)

Lasers are just…cool!

Back in college we used to swipe a 5 mW laser (about the brightness of a cat toy, though higher quality) from the physics lab, take it up onto the roof of the science building, hunker down close by the twenty-foot dome for the long-barrel 10″ telescope, and “lead” people into dinner. Even from 4 stories up and a hundred feet to the side, it would cast a sparkling bright-red dot under an inch across. The wonders of coherent light.

NerdGuy Sidetrack: Coherent Light

First, while the opposite of “coherent” light is “incoherent” light, it doesn’t mean that it babbles meaninglessly like a politician. Light follows all the laws of physics and is rarely incoherent like so many humans.

Sidetrack to the sidetrack. “Non-coherent” light comes in two varieties.

1) UVC is the reason that the holes in the ozone layer are so scary. The ozone blocks Ultra-violet C light waves from reaching us. Which is good as it is carcinogenic and even deadly. The cool thing is, UVC also appears to kill things like Coronavirus and is used to decontaminate things (like airplane interiors) when no fragile humans are around.

2) LEDs are the other form of non-coherent light. Non-coherent technically means that the properties of phase and amplitude vary randomly in space and time. But we don’t care about these today.

Back to incoherent light. It just means that the light waves don’t line up. Imagine an old-fashioned filament light bulb. It just shines light every which way from its heated filament. Two different sections of it are just popping light right in your direction, even though they’re millimetres apart so nothing lines up. Neon lights do this even more because the whole length of the tube is filled with electrically charged gas to make it emit light in all directions. To get any useful brightness in one place, you need a reflector to aim all of the little photons.

Lasers aren’t like that. They go to a great deal of trouble to line up all of the little light waves so that they’re in perfect (-ish) alignment before releasing them into the wild. The light doesn’t spread much as it travels. Instead, it delivers very near its full brightness to the target, whether making your cat dance or confusing students foolish enough to go to dinner past the science building.

This was the 1970s, so folks knew what lasers were but had no experience with them (outside of our department). People would jump and dance aside. Sometimes, just like a cat, they’d follow it for a bit. Several people tried to stomp on it like a bug. Only a very few people would put out a hand to try and block the light to determine the direction of the beam. In either case, we’d always cover the output with our fingers the moment they did that, just to mess with them.

We put the spot in front of one physics major we saw going by. He didn’t even look up, just gave us the finger and kept going.

A Lot of Laser

According to Wikipedia, 1898 was a good year for lasers as weapons. H.G. Wells gave a “Heat-Ray” weapon to the invading Martians in The War of the Worlds. That same year Garrett P. Serviss gave a “disintegrator ray” to the heroes of Edison’s Conquest of Mars. (Mars and death rays must just go together.)

Star Trek of course brought this to the common culture with phasers and even James Bond was not above a laser gun battle in one of the franchise’s worst efforts Moonraker. (Coming in just one ahead of Die Another Day at the very bottom according to IMDB rating.)

Of course, this has not all remained in the land of fiction.

Anti-personnel

Because lasers fire a light beam very efficiently, they can make a blinding light. Literally blinding. So, in 1995 the United Nations banned anti-personnel Blinding Laser Weapons. The US finally signed on in 2009.

That didn’t stop us, and I’m sure many others, from finding a loophole.

Enter the PHASR rifle. Personnel Halting and Stimulation Rifle. Low-intensity. Temporary blindness…hopefully. Yeah, some loophole.

PHASR rifle
The Air Force Research Laboratory had this in 2005. Wonder what they have now!

Many Varieties

For a quick and amusing (in a strictly scientific manner) summary, check out THIS page on Wikipedia (summarized below). Some of these are merely “in development.”

  • Electro-laser – This ionizes the air along the path of the laser and then fires a high-voltage charge along that ionized path. (Set phasers (uh, Tasers?) to stun.)
  • Pulsed energy projectile – Pump enough energy into an infrared pulse to create a destructive plasma explosion at the target.
  • Dazzlers – like the PHASR rifle, but that can blind delicate sensors as well. (We know this is up and running.)
  • Weapons – that can burn holes in things. (Yeah, now we’re talking.)

Airborne

Sure, there’s a whole history of land-based and ship-based testing of lasers, but let’s jump right to the fun part. The YAL-1.

747 Airborne Laser YAL-1 ATL
YAL-1 Airiborne Test Laser (in a 747)

Okay, now we’re talking. Take an old 747-400F (freighter), gut it, and jam a big laser-testing platform up its middle. Low-energy test in 2004, it was eventually able to down multiple test ballistic missiles, during their boost phase, before the project was cancelled and defunded.

Of course that didn’t mean the program of weaponizing lasers was done, it was just that YAL-1 had proven all it needed to. Sadly, after 4 years sitting in the Davis-Monthan boneyard, the one-of-a-kind beastie was scrapped.

Many generations of laser weapons continued under dozens of other names and were mounted on ships, trucks, and airplanes. A cool one was ZEUS, a nice little 10 kW laser mounted on the top of a Humvee for killing ordnance and IEDs from a safe distance.

I wasn’t able to find the power of the final YAL-1 laser, but an article on The International Society of Optics and Photonics describes a 1 MW (MegaWatt – million watts) laser (100 times more powerful than the IED killer and about 16,000 household lamps [back when they were incandescent]). However, it notes that the YAL-1 laser that took out a SCUD missile in testing was in “the kilowatt class.” Yes, it filled a Boeing 747-400 freighter, but this was in 2011. We’ve come a long way since then.

Ghostrider

Skipping over all of the steps in between, the newest version of the Spooky/Spectre/Dragon AC-130-based line of gunships is the “Ghostrider.” And among its massive arsenal is a laser weapon.

A laser weapon that they aren’t talking about much, for obvious reasons. A lot of digging around and I was able to determine that it was probably past the 100 kW range, most likely around 150 kW (over 10,000 nice little LED bulbs…all at once). Now this may not sound like much (just 10-15x the ZEUS IED killer). But let’s backtrack a bit.

How much power do you need? Rockets, missiles, airplanes, satellites…these are all very fussy pieces of equipment that don’t perform well after holes have been burned in them. We know that 10 kW punches holes very nicely. 150 kW will do it 15x better.

There are three other big considerations:

  1. It has to fit inside an AC-130 airplane with a lot of other armament.
  2. You have to be able to fit its power supply on board too. (Another turbine engine?)
  3. It has to work.

That last point is actually the key limiting factor. Fire a laser through something thick, like…air (Worse, moist air. Very worst, clouds or sandstorms.) and you get a problem called “blooming.” The air, and water or whatever not only decreases the beams effectiveness (it is just light, after all, and needs to shine on its target), the moist-dirty air also heats up as it absorbs the energy of the laser beam. This superheats the air, creating turbulence and can even turn the air into a plasma that the laser will turn into an explosion in the air (see the Pulsed Energy Projectile idea above), rather than burning a hole in its target. Literally, lighting the air on fire.

So, 150 kW, is probably as much fun as a gunship needs at this point until we figure out more about how to fire smaller amounts of light–coherently–through that thick air stuff. In the meantime, it let my villains play a bit.

For a long second he looked in her eyes, then reached out and took her hand. Rather than squeezing it with some unwanted but expected sympathy, he moved it to the laser’s joystick. “Get a feel for tracking the vehicle. It’s moving fast, so you’ll need to keep it steady in the crosshairs for longer than you’d think.”

At first she was veering side-to-side. Finally she had a feel for how to keep it steady in the crosshairs, reasonably.

He tapped in a quick series of settings, called in a correction to the cockpit, then pointed at a red Fire button.

He sat back to watch her carefully. His face totally unreadable. 

She wanted him to think well of her.

But she wanted Vasquez dead. So much of the pain in her life—and Mama’s—had been his doing.

Why had a man who headed a cartel, a violent competitor of the one her father worked for, helped them out at all?

And then she knew what other price Mama had paid to Hector Vasquez for their safe passage.

Taz punched and held the Fire button.

His vehicle glowed brightly in the infrared as the supercar heated. It swerved left and right but she kept the beam steady…enough. Finally, perhaps in desperation to escape or perhaps while dying of heat stroke, it swerved too far and rolled.

When it came to rest upside down, she held her aim on the car.

A second later there was the massive bloom of an explosion as the gas tank ruptured.