Police Study of tactical use of Strobe

[KITROBASKIN]

Following a thread that gets the same question asked over and over is not very interesting.

That said:
Have the flashlights with a right angle head been considered as a way to illuminate the target and use the flashlight in an aggressive/defensive way? What disadvantage is there? I understand one can be punished for using a flashlight too aggressively in your country but... We are interested in how the flashlight is specifically used in a hand to hand (or knife) fight.

 

[Grizzlyb]

Hello Kitrobaskin,

First of all, we DON'T use a flashlight in an aggressive way.

And Yes we have considered those. Some had potential, but non of the manufactors worked with us, so we went the other route with a normal light.
Also to find the switches could be a problem. (same problem with side switches.)

Most right angled lights are used for handsfree work.
Then it will hang somewhere and can't be directed exactly.

All lights that are mainly used for blinding/disorienting need to be directed exactly in the eyes of the opponent.
A tactical hotspot at 10 feet is about 1 foot so there is no margin for error.

When you keep a right angle light in your hand it can be used as good as any other light, as long as you have enough training with it (and you have a good momentary switch that you can find 100 time in 100 tries).
But You will also have to develope a "quickdraw" holster for it.

And in fights with knives, we never go hand to hand. That's a certain way to get hurt realy bad.:shakehead

 

[alexl]

Thanks - I have up to page 7 so far so makes sense now.

This particular part is interesting, I will read on to see if any did...

Some manufacturers make oscilating strobes, some make strobes on the 3Hz or 10Hz rim and others between 15Hz and 20Hz. We may assume that those manufacturers all did some sort of research? (but what kind and how thorrow we don't know)

edit - Great on page 8

I cannot find the following specifications on the website for the TDL20 - http://www.edenwebshops.co.uk/en/pt/-eden-tdl-20-tactical-torch.htm

Runtime - in different modes
Candela rating?
Throw metres?

 

[texas cop]

Grizzlyb, I've not looked at this thread for awhile. Just notice the light you use listed, looks nice. I'm using a SolarForce host with near identical size. The dropin is a three amp high/strobe, 450 mah low XM-L2 U2. Its set for strobe, high, low with no memory. Modes are scrolled through with the light pressed against my leg as need be. High is around 900 lumens with a bit larger hot spot. 18650 Panasonic 3400 mah protected for power. I use a bit brighter light as it might need to light up a parking lot or field. After waterproofing it, I put it at the deep end of the pool for two days, no water got in. It does rain in Texas occasionally. Waterproofing was Teflon tape on the head threads, tightened bezel, tightened switch retaining ring, grease on the tail threads. Very happy with the setup. No idea of the strobe but its fast, guessing 12-18 per second.

 

[Roanqoan]

Very informative. Thanks for posting.

 

[alexl]

Hasn't the need for a battery indicator been overlooked? What is the use of a torch if it turns off or dims to a point where it is not effective (or as effective as it could be)

 

[Grizzlyb]

Hi Texas Cop,

You seem to have a good and usable light for your work. It seems to cover most of the situations you can come across.
Being a more tactical instrument then a normal light,our lights always start up in strobe mode, but knowing that, we also hold it against the leg a second and switch to the mode we want. Same technic

What You maybe still need, is a holster that supports the tactical possibility of these lights.
It is no problem to have a good light that works on a different strobe frequency.
It only gets important when you want to design a specific light for a specific job and want all the possible shortcomings ironed out as much as possible.
Having tested it so long and on so many people, we had the chance to focus on many angles we needed and didn't need, that resulted in this straight forward tactical instrument.

Hi Alexl,
Good question:thumbsup:.
The light will work constantly for about 2 hours on high mode.
That situations has, up till now, never occurred with the groups we work with.

When ever the LEO feels the need, he takes a fully charged battery from the charger and puts the used one back. (some do that automatically every few days or so)
So he never has to look for an indicator.
Indicators are a non necessary extra, extra's cost extra money and raise the chance of stuff breaking down.
Everything according to the K I S S principle.

 

[alexl]

Thank you

How do you gauge 2 hours of use? I would 'feel the need' every few times I had been working (If I was a LEO that is) If a light dims right down or turns off in a big field it doesn't matter so much as if you are about to be bottled/stabbed etc! Interesting thread and great replies, even if I am very new to torches and dont fully understand their simple yet complex workings

 

[Grizzlyb]

They don't have to gauge.
As I said, it is easy to swap batteries when You start your shift (when you realy want that and feel the need).
It is better than have to look at indicators all the time and worry if the indicator still works.

In Europe most LEO's work in the City.
There is always so much light that they very seldom need an extra light source.
A typical shift for a LEO (in Holland) is 3 to 4 night's in a 4 week period. They use a light maybe 1 or 2 times a shift at the most.
Total use can be measured in seconds more then in minutes.
So when they change a battery once a month when they start nightshift, it is more then enough.

 

[RI Chevy]

Wow. You guys are slow over there. LOL

 

[donjoe]

5. At least 250lm throw type beam at up to 2 hours. Higher lumens (read lux) is possible, but no less. (The effects of blinding and disorientation are optimal enough on that intensity. On lower lm the effect is less and not optimal.)

Do you have an equivalent specification in candela? Since we're talking about a very directional effect (toward a target's eyes), it seems more relevant to talk about how many cd you need in a strobing flashlight in order to optimize the effect.

I saw Max mention a range of 20k-30k cd as optimal, but I think he was talking about a continuous beam and I wanted your opinion on this, specifically in the context of the strobe discussion. So far you've only mentioned something like 9k cd, but you didn't specify if you thought that was the optimal level to achieve target disorientation with minimal effects on yourself or your colleagues.

 

[Grizzlyb]

Good thinking Donjoe,

We indeed have a minimum on cd on a specified field at several distances.
Minimum is 9000lux at 1 meter,
At 3 meter (max fighting distance) a minimum of 1000lux in center of the hotspot (throw) with max diameter of 20 cm (at the side still min. 800lux).
At 1.5 meter the outside of the light circle may not have more than 15 lux.
At 3 meter the max light circle should not be more than 2.5 meter in diameter.
This way we are sure not to have lights with a wide beam that will blind/hinder the user to much due to rebounce from walls/ceiling.
These figures are "more or less" but this way you have a better picture of it.

Not to say that this is the best, but it works the best for our use, with as little negative side effects as possible.

 

[donjoe]

Minimum is 9000lux at 1 meter,
At 3 meter (max fighting distance) a minimum of 1000lux in center of the hotspot (throw) with max diameter of 20 cm

OK, so both these specs suggest you want to throw at least ~63 lm into that very tight hotspot that's 0.2 m in diameter at 3 m distance. Unless my Wikipedia-based math is out of whack, this translates to an intensity minimum of 18 kcd for that hotspot, which is pretty close to what Max was talking about. So thanks for the confirmation then!

 

[bluemax_1]

OK, so both these specs suggest you want to throw at least ~63 lm into that very tight hotspot that's 0.2 m in diameter at 3 m distance. Unless my Wikipedia-based math is out of whack, this translates to an intensity minimum of 18 kcd for that hotspot, which is pretty close to what Max was talking about. So thanks for the confirmation then!

I think you have your measurements a little confused. As far as flashlights go, you can pretty much take lux at 1 meter = candela.


Max

 

[donjoe]

Yep, apparently I did get confused - those two specs I quoted were actually quite different:
9000 lux @ 1 m => 31.36 lm into that beam that makes a hotspot with a 0.2 m diameter @ 3 m, so 9 kcd in this case
1000 lux @ 3 m => 62.7 lm into the same beam, so ~18 kcd in this case.

Now if we put them together, we still get the conclusion that the minimum required intensity is actually 18 kcd along the direction of maximum output. I don't know why there's this difference between the specs, maybe the first spec was some kind of average for the whole beam pattern, i.e. hotspot + spill.

 

[bluemax_1]

Yep, apparently I did get confused - those two specs I quoted were actually quite different:
9000 lux @ 1 m => 31.36 lm into that beam that makes a hotspot with a 0.2 m diameter @ 3 m, so 9 kcd in this case
1000 lux @ 3 m => 62.7 lm into the same beam, so ~18 kcd in this case.

Now if we put them together, we still get the conclusion that the minimum required intensity is actually 18 kcd along the direction of maximum output. I don't know why there's this difference between the specs, maybe the first spec was some kind of average for the whole beam pattern, i.e. hotspot + spill.

Your calculations are still off.

The general conversion for Candela from measured lux at X meters is:
Candela = (lux) x (square of distance in meters).

So for 1000lux at 3m, you'd get 1000 x (3x3) = 9000cd.


Max

 

[donjoe]

Got me again. I just can't get any good days for science, apparently.

 

[ghodan]

Anybody know the effect of a flashlight on a aggressive dog that has intend on attacking you or somebody next to you.
Do dogs get blinded more easy then humans?
Does strobe have more or less effect on dogs?

 

[bluemax_1]

Anybody know the effect of a flashlight on a aggressive dog that has intend on attacking you or somebody next to you.
Do dogs get blinded more easy then humans?
Does strobe have more or less effect on dogs?

Anecdotal evidence is sparse on this. Some folks have claimed that it worked, some have claimed that it didn't even slow them down. I'm inclined to think it's going to be intensity dependant. Dogs tend to have better low light vision than humans, but I'm not sure how that translates in comparison to humans as far as being blinded by a bright light goes.

I'm also unaware if there's a specific frequency range for a strobe that affects them the way it does humans.

What I DO know is that animals are smart enough to be wary of charging something they can't see. One thing I tried a long time ago was to hit a charging dog in the eyes with a bright spotlight and yell at it. It DID screech to a stop, but I don't know if yelling at it alone, without the spotlight might have had the same effect.

I'm inclined to think that the combination of not being able to see what it was charging at PLUS the loud noise, startled it enough to make it stop, but I wouldn't trust using just a flashlight to ward off aggressive dogs. If I did, it would have to be one heckuva bright light.


Max

 

[donjoe]

It's funny you should ask that, because that was exactly my primary intended use when I got my first "tacti-cool" flashlight. I never got to test it because I later convinced myself to give an ultrasound device a try, so when push came to shove I preferred to pull out that one (while also having the flashlight on me). So all I can tell you for sure on this subject, after two real-world tests (actual aggresive dogs coming at me, not pets and not dogs behind fences), is that you can have a reasonable expectation that if you're up against a single aggressive dog that happens to not be deaf you'll be able to keep it at a respectable distance (10 steps/yards or so) by blasting it with ultrasound and yelling at it at the same time.