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Old 28 May 2009, 18:07   #11
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From the FAQ on the website:

6. Won't they stun the pilot/captain whose attention I'm trying to get?

No. When the fan of light crosses your target's vision it will appear as a brilliant flash in the distance and will in no way impair their night vision.

Comparison of cockpit illumination power densities of Rescue Laser Flare® emergency signalling device vs. typical laser pointer

Let’s compare the amount of laser light power which illuminates an aircraft cockpit from the Rescue Laser to that of a typical laser pointer, at a common signalling distance of 1.5 miles. The laser power level illuminating the cockpit and hitting the pilot’s eye from the Rescue Laser is about one trillionth of a watt. This power level is very low because the Rescue Laser begins with a very small amount of laser light and then creates a very long 2 dimensional fan (line) of light further reducing the power density of the light. This level can be easily detected, but will not obscure pilot vision in any way.

However, because the light from the laser pointer remains in a relatively small one-dimensional pencil thin beam, the laser beam spot size at the aircraft is about 240CM (8 ft) in diameter. Because all of this light is concentrated in a relatively small spot, rather than spread out in a long line like the Rescue Laser, the power density impinging on the pilot’s eye is about 1,000 times greater from the laser pointer, at this distance.

Therefore, although the signalling capability of the Rescue Laser emergency rescue and signalling device remains effective for signalling SAR aircraft, the power levels (brightness) of the Rescue Laser is reduced by one thousand times, this is a level where visual flight acuity is not affected.

It should be noted that even the laser pointer’s output although bright, is still about ten thousand times lower than the power level where eye injury can occur, at this distance.

Supporting analysis:

Rescue Laser Flare®
7mW
5degree fan angle (87mrad)
1mrad narrow axis divergence angle
1.5miles = 2,414 meters
Area of laser line at 2,414 Meters = 5.07 Million cm2
Watts/cm2 = .007 / 5,070,000cm2 = 1.38 x 10-9 Watt/cm2 = 0.000,000,001,4Watts/cm2

Typical Laser Pointer
5mW
1mrad divergence
1.5miles = 2,414 meters
Area of spot at 2,414 meters = 45,745 cm2
Watts/cm2 = .005/45,745cm2 = 1.1x10-7 Watt/cm2 = 0.000,000,1Watts/cm2


The laser light power density from the laser pointer is 1,000 times higher than that from the Laser Flare, when both measured at 1.5 miles

Sorry for techincal explaination! These figures have been supplied by the manufactuer, but this what makes the difference between Pointers and Flares.


Regards

Scott
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Old 28 May 2009, 18:51   #12
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Any Questions on this product feel free to ask me, and I will do my best to honestly answer them.


Scott
Do we get a discount?
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Old 28 May 2009, 19:10   #13
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not causing "harm" is not the same thing as not "blinding" a heli crew. All "laser pointers" generally available in the UK will normally be class 2 laser devices and so, in theory, present no risk of eye damage in normal (mis)use - but if you shine it in your eye it will "dazzle" you and cause the "blindness" that pilots are complaining about.

I think it is very unlikely that these devices will not cause some degree of dazzle for a pilot operating in darkness - especially if he is wearing any kind of night vision/image intensifier.

We've all experienced car headlights - same issue but potentially much worse.
Gen 3 nvgs are pretty good at filtering out bright lights.

It would be very easy to have a filter to block a laser as they have such a narrow wavelength - all other light will get through.

My main concerns are
a: Anyone seeing it will think - look there's some twat with a laser pointer.

b: Potential for misuse - much easier to trigger than a flare and much more "fun" - could turn into "The little boy who cried wolf". Not many people carry flares in their pockets just for a laugh.

c. Due to potential misuse of laser pointers in general pilots may well start using filters/goggles to block out that particular wavelength.

I would buy one though!!!
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Old 29 May 2009, 02:15   #14
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My main concerns are
a: Anyone seeing it will think - look there's some twat with a laser pointer.
That's a very good point.
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Old 29 May 2009, 04:06   #15
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It would be very easy to have a filter to block a laser as they have such a narrow wavelength - all other light will get through.
its not as easy as it seems at first. there are several different wavelengths in use for the "domestic" market and with solid state lasers the exact wavelength is dependent on a number of factors including temperature - which isn't usually stabilised on cheap devices. Then of course there are hundreds of different - less portable laser wavelengths that might be of concern for malicious use.[/quote]
Quote:
a: Anyone seeing it will think - look there's some twat with a laser pointer.
thats probably a valid point - I guess the manufacturers would argue it is distinctive - but unless I was looking for someone in distress I probably wouldn't "click" and suspect the public more so.
Quote:
b: Potential for misuse - much easier to trigger than a flare and much more "fun" - could turn into "The little boy who cried wolf". Not many people carry flares in their pockets just for a laugh.
but the RNLI/CG do respond to numerous reports of red flares each year which are never traced to a distress situation and are often assumed to be malicious.
[/quote]
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Old 29 May 2009, 06:54   #16
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The way I would think Laser Flares are used:

1) VHF Radio Call or the dreaded Mobile Phone call to alert to distress, you tell them where you are roughly and you have Rescue Laser Flare.

2) As Rescue Service approaches you use Laser Flare to attract attention to your exact location. (As in letting off a Pin point flare in old days, the brightness of the pin point flare prob would dazle the pilots NVG. As well as the pin point only lasting 60 Secs.)

The added feature is that it can find Retro-Reflective Material, ie can help to locate that MOB at night.

True case Rescue:

On Saturday, August 02, 2003, at 23:34hrs Sgt. Mike ter Kuile, Tactical Flight Officer, and Chief Pilot Brendan McCormick for Calgary Police Air Services Unit, were requested to assist the RCMP and the Calgary Fire Department in a search for 4 rafters that were overdue by approximately 4 hours. Upon arrival at the scene it was noted that 2 police units and 3 trucks from the Fire Department had been searching for the victims along with members of their families.

An initial search was started in the area using the Wescam 16DS FLIR on the MD-520N. At approximately 0030hrs, the victims were located by the flight crew approximately 5NM from the search area on a sandbar. After landing nearby, the victims were checked by the Flight Officer for injuries and it was discovered that 2 of the 4 had lost their footwear when a raft was punctured. All were cold and wet and suffering from mild hypothermia. There were 3 females and 1 male with ages ranging from 17 to 23.

They had attempted to contact family members and the police via cell phone however their only phone had gotten wet and was not functional. Due to the remote location of the victims, their lack of footwear and clothing and the advanced time of day, it was decided to transport the rafters by air. Two of the four victims were loaded into HAWC 1 and transported to an LZ set up by Calgary Fire Department personnel. The remaining 2 rafters were left with a Rescue Laser Flare to assist the flight crew with relocating them for the 2nd trip. This was the 1st opportunity for the Unit to test the rescue laser and it proved to be extremely visible from at least 3 NM away from the helicopter. The victims were located in a shallow river valley and were surrounded by trees that added to their poor visibility.

One of the primary benefits that resulted from the use of the Rescue Laser was the reassurance it provided to the other two victims that the Flight Crew would have no difficulty finding them again thanks to the effectiveness of the laser as both a position marker and signaling device. Although not a critical rescue it was a good opportunity for the crew members to utilize their respective skills and equipment and to gain insight into the many life-saving applications afforded by the use of the Rescue Lasers.


S.

Discount: Due to the current High Dollar Rate, we have resisted in increasing the price of the flares hoping for the dollar to recover, so for one off purchases we can not discount at present.
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Old 29 May 2009, 07:22   #17
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Quote:
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but the RNLI/CG do respond to numerous reports of red flares each year which are never traced to a distress situation and are often assumed to be malicious.
Not really. In general, they'll be put down as unexplained or a false alarm with good intentions. Very very few would be thought of as malicious
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Old 29 May 2009, 10:20   #18
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Not really. In general, they'll be put down as unexplained or a false alarm with good intentions. Very very few would be thought of as malicious


I have only ever seen one flare that had been let off(not counting Nov 5TH etc) and that was a few miles inland.

Flares are expenisve one shot devices to muck around with. People tend to treat them with respect. They are NOT the sort of thing you see in common use.

I have seen countless laser pointers and other laser devices in use. When these things end up on Ebay it will be cool to have your personal Disco laser which is basically what a laser flare is - disco lasers also give out a broad fan of light!!!

To be honest even I wouldn't be able to resist temptation and use one from time to time - with the range they have it could end up very misleading. It is much easier to just "give it a quick go to see what it does" than it is to launch a flare.
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Old 29 May 2009, 11:46   #19
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Codprawn, I think we may be at cross purposes. The quote from my post which you have used here was in response to Polwart's comment ...

Quote:
RNLI/CG do respond to numerous reports of red flares each year which are never traced to a distress situation and are often assumed to be malicious
... and I was just observing that in my experience with the RNLI (30 years this year) it is very rare that a report of a flare sighting would be viewed as "malicious". Maybe that could change if lasers become more popular and if the number of false alarms goes up, but I think the general view of all the rescue services would be to be very sensitive to any possibility that they might discourage people from reporting potential distress signals.
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Old 29 May 2009, 12:14   #20
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Codprawn, I think we may be at cross purposes. The quote from my post which you have used here was in response to Polwart's comment ...
Yup quoted on the wrong one sorry!!!
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