Canal Defence Light | Hacker News Reader

Canal Defence Light

en.wikipedia.org

33 pointsvinnyglennon16 comments

The UK was very fond of making specialised of tanks in WW2 - notably "Hobart's Funnies":

https://en.wikipedia.org/wiki/Hobart's_Funnies

The Soviets also used searchlights to dazzle enemies during attacks - particularly that attack on Seelow Heights:

https://en.wikipedia.org/wiki/Battle_of_the_Seelow_Heights

"The idea is credited to a Greek citizen, Marcel Mitzakis, who devised the system for the de Thoren Syndicate in the 1930s; they were advised by J F C Fuller."

https://en.wikipedia.org/wiki/Archimedes#Heat_ray

Putting his heritage to good use it seems :)

I remember seeing one of these at the Tank Museum in Dorset, UK. If you're in the area, it's worth a visit. The weird contraptions mounted on some WW2 tanks must be seen to be believed.

According to Wikipedia, you saw the only one in existence with its original tank model/structure.

Can't imagine driving one of these into battle. Seems like it'd be a giant "shoot me first!" announcement.

I thought that too but, if it's too bright to look at, you can't hit it. Or maybe you have retreat beyond your weapons effective range just so you aim at it.

Though I'm sure the enemy would have eventually found some welding glass or even oil-smeared glass

> Though I'm sure the enemy would have eventually found some welding glass or even oil-smeared glass

You don't exactly carry either for an amphibious assault. And once beaten back, there likely wouldn't be a second attempt.

Not that much of a problem for defensive positions. They can be fortified, and successfully attacking a tank is difficult either way, especially for an amphibious force with limited munitions and firepower available.

And without night vision gear (prototypes were only available by 1945), the only options are flares (which would aid attackers as much as defenders), or search lights (which are much harder to destroy this way).

"Curiously, the actual use of the system resembled its name, which was intended to be spurious."

Names are important.

So why is it no longer in use? Seems to me that emitting an extremely bright flashing light is a great way to disorientate enemy infantry in close quarter combat scenarios.

Blinding flashes of light are widely used by infantry forces of several states, including the US, in the form of flashbangs[1]. They are much smaller and cheaper than a searchlight system mounted on a tank, and being deployed as a hand grenade allows their use indoors.

[1] https://en.wikipedia.org/wiki/Stun_grenade

I'm aware. I was specifically talking about vehicles, but I see that I didn't include that information in my previous post. I think with present day technology the lights could be a lot smaller than searchlights no?

I think now the preference is to use night vision, IR sensors or the like and remain as concealed as possible.

From the linked wikipedia article:

"There was brief interest in resurrecting a CDL on M4 Sherman design (T52) that had started in 1944 but it was recognized that four battalions could be fitted with normal searchlights for the cost of a single CDL tank."

Which sounds like a good lesson in right-sizing a task.

I wonder if it's possible to create an extremely disorienting strobe system, that an operator would carry around, but the operator has special optics that cancel out the strobe's effects. Maybe his goggles are special night vision ones that have a framerate synchronized with the strobe, so it looks like it's always light (or dark).

Maybe add a seizure-inducing harmonic to the light pattern for good measure.

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