laser flares etc and some comments from Greatland lasers

[tim_ber]

I always carry proper flares. Parachute ones too. I don't like it and I take precautions to minimize accidents and I also look after my flares so they suffer no damage.

But, as most of us know from the accident of a poor gentleman instructor, accidents can occur (the white flare demo with an indate flare).

Greatland lasers offer a range of laser flares, Odeo offer a laser flare. Greatland lasers state in a forum that odeo Flare 'used' a patent of greatland's, but I don't know if that is true.

In the text at the bottom - taken from a forum, greatland laser make some valid points about the odeo flare I believe.

NOW, how many of you carry flares in your pocket in case you fall overbord? The only ones that fit are pretty much the mini flares with the little yellow firing mechanism and I don't think it is a great idea to have explosives in one's pocket.

I sailed recently (it was cold) with a round the world race skipper. He said he carried a light stick in his pocket in case he fell overboard to aid the crew to pick him up; you know, bend it, and it lights.

In my pocket I had a hand warmer, knife, whistle obvioulsy, and a laser flare and i am just an amateur that prepares for the worst, hopes for the best and have never had a drama at sea.

But the laser flares are expensive $99 the cheapest. So I developed a laser flare that runs from 2 AAA batts, emits a better cone of light than greatland lasers, is less then 5mW so safe for brief flash across eyes (odeo flare emit 5mW continuously I think) and I make it in green and red.

People often state on here that green is bad. Possibly valid. If I had just fallen overboard and was 100 yards from boat, my red laser flare would do the trick and pinpoint me for pick up. BUT if I was in mid ocean, a flashing red could be a bouy - a flashing green could be too, but the green is more visible than the red and for a greater distance, so in that case I'd choose green.

Anyway, for £20 - £25 I can make these (that would be the RRP I mean) and I am wondering if there is a market for them. I have links with chandlers that stock some of my products already, but you are the end users and the important guys, so I thought I'd ask your opinions. It fiits into one's pocket and I think that is the main thing and it is not going to send magnesium into your guts. The odeo flare is too large. Greatland are too expensive.

What doyou think?

Cheers - and don't fall overboard.


Pasted from a forum about mountaineering I believe. It is greatland laser respondin to a poster that mentioned the odeo flare;
Hi all

"Greatland here. I wouldn't jump up and down for a product or company that copies anothers patented technology and puts a spin on it thinking they have a cool tool. Greatland patented a rotating laser distress signal also but elected not to pursue a product as performance degrades with the speed of rotation, everyone knows that.

We also found that rotating a 5mW laser projection only had a range of a few miles and looked like just another red light, there are many products that can easily achieve that. Being an Alaskan pilot for over 35 years and searching the vastness for any sign of survivors I knew the most important requirement for a distress signal product was RANGE, DURATION and UNIQUENESS, especially from background lighting.

Line of sight on the surface is only a couple of miles. BUT!! You can see an aircraft over 50 miles away. The last thing you as a possible survivor want to see is a passerby saying adios to your ODEO because they were a couple of more miles away and didn't see you.

Great idea though, too bad it doesn't work as well as the Rescue Laser Flare."

 

[maxi77]

Now tell me just how will a pilot coming to your aid first see that your laser is a rescue aid, and more importantly know with certainty that your laser will not harm his eyes.

 

[sailor211]

It's just a light it has no meaning and there is no reason for someone to know you are in need of help. No more than seeing a red head touch flickering from a close by yachts cockpit. Or a port hand light from a small boat. Ok a bit more range but still a red light

 

[tim_ber]

Now tell me just how will a pilot coming to your aid first see that your laser is a rescue aid, and more importantly know with certainty that your laser will not harm his eyes.

Well according to the Greatland laser website (the expensive chappies) they state the following (or click on the link to see it in a better format)

And I guess it is a bit like change (like the change to this forum layout) - things change, become accredited and accepted. How long have we been relying upon exposives now? And yes, there is no alternative to rocket flares yet.

As to damage to his eyes - it would be his judgement call. The flash is very intermittent. If he was searching for someone and saw a flash, what would he do? Open to guesses. If he was not searching and saw a flash, then maybe he would dismiss it and fly on by, whereas with a rocket flare he would be less likely to dismiss it, but who falls overboard with a rocket flare in their pocket? But a laser flare can always be in your pocket. (say you are on watch on your own and not clipped on - I always clip on in that situation though).

http://www.greatlandlaser.com/faq.html

Federal Law allows an EXCEPTION for laser emergency signaling devices to send a distress signal to aircraft.

In February 2012, the United States Congress passed into law HR658 authorizing appropriations for the Federal Aviation Administration (FAA) for fiscal years 2011 through 2014. Included in the law is Section 311 "Prohibition Against Aiming a Laser Pointer at an Aircraft". Section 311 39A(c)(3) on page 56 specifically exempts "an individual using a laser emergency signaling devices to send an emergency distress signal." Greatland Laser has sold its patented laser emergency signaling devices throughout the world for over 10 years. We have never had a safety issue with the products. Under the exception provided in this federal law, Rescue Laser are legal to signal an aircraft for help in an emergency.

For an explanation as to why the Rescue Lasers are safe when a standard laser pointer can cause problems, please refer to "How Do They Work".

What's the difference between the 3 Rescue Lasers?
Why are they better than traditional pyrotechnic flares?
How do Rescue Laser products work?
Wouldn't my laser pointer do the same thing?
Are they safe to look at?
Won't they stun the pilot/captain whose attention I'm trying to get?
When I shine my Rescue laser in the distance, I can't see anything. Why?
I'm holding my laser in the air and my friend can't see me. Why?
Does it matter which way the laser line is pointed? If so, how will I be able to tell?

1. What's the difference between the 3 Rescue Lasers?

While all three products have the same signaling capacity, they do vary in signaling time, design and distance. You can signal further using the Green Laser Flare® but the green laser diode is more fragile, uses more energy to operate and has a smaller temperature range.

For a complete comparison please see below:
Rescue Laser Light Rescue Laser Flare Magnum ® Green Rescue Laser Flare ®
Batteries CR123 Lithium AA CR123 Lithium
Operating Time on Batteries 40 hours 72 hours 5 hours
Waterproof Depth 80 ft. 80 ft. 80 ft.
Operates Below 0° ? Yes Yes, with AA lithium batteries
* alkaline batteries included No
Laser Diode Red
10,000 hr. meantime to failure Red
10,000 hr. meantime to failure Green
5,000 hr. meantime to failure
Signal Distance 20 miles at night
1-3 miles daytime 20 miles at night
1-3 miles daytime 30 miles at night
3-5 miles daytime
Warranty Limited Lifetime Warranty Limited Lifetime Warranty 180-day Warranty

back to top

2. Why are they better than traditional pyrotechnic flares?
Rescue Lasers Pyrotechnic Flares
Signal Duration 5-72 hrs. depending on product 1 minute
Detection Capability Locates reflective material None
Fire Risk No risk Flammable
Environmental Risk Environmentally safe Hazardous Material
Visibility Long duration - Easy to locate source Short duration - Difficult to locate source
Resuable? Yes No

back to top

3. How do Rescue Laser products work?

See our details illustrations on the How Do They Work? page.

back to top

4. Wouldn't my laser pointer do the same thing?

No. In order to signal at a distance with a laser pointer, you would have to accurately hit your target in the eye in order for them to see you. Our products draw a line which fans out the further it goes. At 16 miles, you have a 6,000 ft. long fan of light with which to hit your target. Please see How Our Products Work

back to top

5. Are they safe to look at?

Yes. Our lasers are classified by the The United States Food and Drug Administration (FDA) as a Class IIIA(Class IIIR) Laser Product. Just like any other light, however, it isn't advisable to point it directly in the eye at short range for an extended period of time. Please refer to the FDA's Consumer Health information publication http://www.fda.gov/downloads/ForConsumers/ConsumerUpdates/UCM167564.pdf explaining the different types of laser devices and laser safety. Rescue Laser can safely be used to signal an aircraft for help when you are in distress. Unlike higher powered lasers that may be dangerous if pointed at an aircraft, Rescue Lasers will not cause eye injury nor flash blindness when used to signal a pilot in an aircraft. Rescue Lasers have been on the market since 2001 and have never caused an injury!

back to top

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 signaling 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 signaling 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 signaling capability of the Rescue Laser emergency rescue and signaling device remains effective for signaling 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
5 degree fan angle (87 mrad)
1mrad narrow axis divergence angle
1.5 miles = 2,414 meters
Area of laser line at 2,414 meters = 5.07 Million cm2
Watts/cm2 = .007 / 5,070,000 cm2 = 1.30 x 10-9 W/cm2 = 0.0000000014 W/cm2

Typical Laser Pointer
5mW
1mrad divergence angle
1.5 miles = 2,414 meters
Area of spot at 2,414 meters = 45,745 cm2
Watts/cm2 = .005 / 45,745 cm2 = 1.1 x 10-7 W/cm2 = 0.0000001 W/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.

back to top

7. When I shine my Rescue laser in the distance, I can't see anything. Why?

Lasers are directional lights. Unless the fan of light produced by our products crosses your line of vision or you pass over a retro-reflective material, you will not see the light when aiming at a distance.

back to top

8. I'm holding my laser in the air and my friend can't see me. Why?

If you were to just hold the laser without aiming while slowly moving it back and forth you will probably not be visible to your target. Because lasers are directional lights, the fan of light must cross their line of vision. This is accomplished by first aiming at your target and then moving the laser slowly back and forth. Every time the fan of light crosses their vision they will see a brilliant red flash.

back to top

9. Does it matter which way the laser line is pointed? If so, how will I be able to tell?

Yes, it does matter. The 6000 ft. high fan of light produced at 16 miles gives to the greatest signaling area. The laser line should be pointed vertically at your target. In order to tell which way the line is directed, point the laser a few feet in front of you on the ground.

 

[tim_ber]

It's just a light it has no meaning and there is no reason for someone to know you are in need of help. No more than seeing a red head touch flickering from a close by yachts cockpit. Or a port hand light from a small boat. Ok a bit more range but still a red light

But why would a red handheld flare have more meaning in your scenario?

 

[maxi77]

Well according to the Greatland laser website (the expensive chappies) they state the following (or click on the link to see it in a better format)

And I guess it is a bit like change (like the change to this forum layout) - things change, become accredited and accepted. How long have we been relying upon exposives now? And yes, there is no alternative to rocket flares yet.

snipped to allow it to be posted in this 'improved' format

9. Does it matter which way the laser line is pointed? If so, how will I be able to tell?

Yes, it does matter. The 6000 ft. high fan of light produced at 16 miles gives to the greatest signaling area. The laser line should be pointed vertically at your target. In order to tell which way the line is directed, point the laser a few feet in front of you on the ground.

All good stuff I am sure but it still does not tell any one how this light will be recognised as a distress signal, not some prate with a laser pointer, and equally I see nothing that tells a pilot this is a safe laser not a dangerous pointer. The fact the FAA says pointing a laser designed for rescue purposes is not against the law is all well and good but how does the observer know this is a rescue laser and is eye safe.

This is the point laser advocates keep missing, these devices have limited value if they are not emitting a recognised light pattern that tells all it is a call for help and is safe especially for aircrew and the users. There are no national or international standards as far as I am aware and until there is I see limited value in these devices and I would certainly not touch a homemade one with a bargepole unless some one had spent a lot of money testing it's safety. That is partly why I suspect the commercial lasers cost a trifle more than the home made one. Finally most laser damage to the eye is permanent, and even temporary damage can be very very painful

 

[tim_ber]

Yes,

All good points, but how many people know that 112 (it is 112 isn't it?) is better than dialling 999 - as discussed on here sometime ago.

Perhaps the maritime industry needs some research and accreditation and publicity into lasers so we can move on from the handheld flares (and only handhelds at the moment).

Also, a fire in a bucket at the forepeak, is in many old text books, but who would recognize that as a distress call and not a BBQ? Actually, smoke would be better than a laser perhaps. Are those mole smoke devices safe to have in ones pocket? Because then I could swap to that (for daytime use). Everyone would come to the rescure of a 'fire' surely? Doesn't solve nightime issue though. But anyway, for my crew, across oceans, we would all know that a flashing green, was one of us in the water and we'd best turn around toute suite and pick the poor bugger up before the cold or sharks (depending upon where we were) got them first!

Just as we should all know about the 112 business.

How a pilot would know it is safe is very valid and must be solved. So far this has not been addressed by Greatland or OdeoFlare. For a pilot, it could still be a spotty teenager shining a 30mW green into the air with no IR filter attached (and IR WILL make one blind).

 

[blackbeard]

Thanks for this, which explains a lot.

Seems to me that a conventional pyrotechnic flare, and the laser flare, do fundamentally DIFFERENT things.

The pyrotechnic flare is a signal to EVERYONE for miles around that you need help.

The laser flare is a signal to the aircraft or lifeboat or whatever, which already knows you are in trouble and is looking for you, to say "I am here". It's no use as a primary indicator of distress since a. you (potential rescuee) would need to carefully scan around the horizon and you probably haven't got time to do that, and b. it's just a flickering red (or green) light which wouldn't be recognised as a distress signal unless the potential rescuer knew that someone down there was in distress.

So, there is a use of both devices.

Have I got that right?

I must admit, though, that if I were near lots of other boats my first thought might be a pyrotechnic flare; if I were well offshore it would be that red button on the radio, or an EPIRB, or a PLB transmitting on the same frequencies as the EPIRB (both with GPS so they give a precise location). EPIRBs and PLBs also give a radio homing signal which aircraft and lifeboats can pick up. If I fell overboard while single-handed and well offshore, I would rather like to have a PLB in my pocket as a first choice.

 

[blackbeard]

....
Also, a fire in a bucket at the forepeak, is in many old text books, but who would recognize that as a distress call and not a BBQ? Actually, smoke would be better than a laser perhaps. Are those mole smoke devices safe to have in ones pocket? Because then I could swap to that (for daytime use). Everyone would come to the rescure of a 'fire' surely?
.....

No need for a mole smoke, an ordinary orange smoke flare will do nicely.

 

[maxi77]

Yes,




How a pilot would know it is safe is very valid and must be solved. So far this has not been addressed by Greatland or OdeoFlare. For a pilot, it could still be a spotty teenager shining a 30mW green into the air with no IR filter attached (and IR WILL make one blind).

IR is not the problem in these cases, the point about lasers is they are very narrow band sources, a green laser will not give of any signal in the IR range. If you can see a laser it is potentially eye dangerous because it is at a wavelength the eye is optimised to transmit energy on to the retina. Retina damage caused by lasers is normally permanent. Some of the IR wavelengths are equally well transmitted through the eye onto the retina, particularly the 1 micron wavelength used in many military lasers. Longer wavelengths are not so well transmitted through the aqueous matter of the eye so the risk is heating of this part of the eye, which means you can be subject to higher energy lasers without permanent damage. So many IR lasers are in fact much safer than visible lasers.

It is interesting to see how many people shy away from pyrotechnics yet are happy to play with devices that can make them blind.

One of the real problems is that the laser diode can be made very cheaply, but without very good quality control the output can vary substantially across a batch, meaning some are lowered powered that advertised thus safer, but many are also over powered and a proportion are dangerously high. This is partly why responsible manufacturers of such devices cannot sell them cheaply, there is too much quality control needed all the way through the process from the manufacture of the basic diode up to the production of the final product

 

[tim_ber]

Thanks for this, which explains a lot.

Seems to me that a conventional pyrotechnic flare, and the laser flare, do fundamentally DIFFERENT things.

The pyrotechnic flare is a signal to EVERYONE for miles around that you need help.

The laser flare is a signal to the aircraft or lifeboat or whatever, which already knows you are in trouble and is looking for you, to say "I am here". It's no use as a primary indicator of distress since a. you (potential rescuee) would need to carefully scan around the horizon and you probably haven't got time to do that, and b. it's just a flickering red (or green) light which wouldn't be recognised as a distress signal unless the potential rescuer knew that someone down there was in distress.

So, there is a use of both devices.

Have I got that right?

I must admit, though, that if I were near lots of other boats my first thought might be a pyrotechnic flare; if I were well offshore it would be that red button on the radio, or an EPIRB, or a PLB transmitting on the same frequencies as the EPIRB (both with GPS so they give a precise location). EPIRBs and PLBs also give a radio homing signal which aircraft and lifeboats can pick up. If I fell overboard while single-handed and well offshore, I would rather like to have a PLB in my pocket as a first choice.

Yes, you got it in one.

Few people fall overboard with a flare in their pocket.
£25 will solve that.
A personal EPIRB is ideal if mid-ocean, but even it is dark and the crew know you have just gone over, you would use the £25 laser and not the epirb.

Have a virtual prize my friend.

 

[maxi77]

Yes, you got it in one.

Few people fall overboard with a flare in their pocket.
£25 will solve that.
A personal EPIRB is ideal if mid-ocean, but even it is dark and the crew know you have just gone over, you would use the £25 laser and not the epirb.

Have a virtual prize my friend.

All of the laser devices discussed so far cost substantially more that £25, and a decent waterproof torch will probably do the same and be safer for the users. Of course there are also radio based devices that can help to for the straight MOB though more expensive that £25 again.

 

[tim_ber]

IR is not the problem in these cases, the point about lasers is they are very narrow band sources, a green laser will not give of any signal in the IR range. If you can see a laser it is potentially eye dangerous because it is at a wavelength the eye is optimised to transmit energy on to the retina. Retina damage caused by lasers is normally permanent. Some of the IR wavelengths are equally well transmitted through the eye onto the retina, particularly the 1 micron wavelength used in many military lasers. Longer wavelengths are not so well transmitted through the aqueous matter of the eye so the risk is heating of this part of the eye, which means you can be subject to higher energy lasers without permanent damage. So many IR lasers are in fact much safer than visible lasers.

It is interesting to see how many people shy away from pyrotechnics yet are happy to play with devices that can make them blind.

One of the real problems is that the laser diode can be made very cheaply, but without very good quality control the output can vary substantially across a batch, meaning some are lowered powered that advertised thus safer, but many are also over powered and a proportion are dangerously high. This is partly why responsible manufacturers of such devices cannot sell them cheaply, there is too much quality control needed all the way through the process from the manufacture of the basic diode up to the production of the final product

I don't know if it was you that said it, but my devices are certainly not home made. I simply design things differently from Greatland and have small overheads etc. And of course, many businesses want huge margins. The odeo flare is pretty cheap £149 for the motors, lasers, plastic forming that goes into it.

Green lasers absloutley DO give off IR. They are made from red laser diodes with a 'crystal' after the diode that creates the green wavelength. They must have an IR filter and a lot of the dodgy teenager ones do not have the IR filter.

Laser flares do NOT produce a point of light - that is the success of them. A pinpoint laser is uselessin this situation.

Greatland lasers produce the supposed cone (which it is not in actual fact), but they produce a line.

My device however does produce a cone and I am happy with it.

"It is interesting to see how many people shy away from pyrotechnics yet are happy to play with devices that can make them blind."

Let us remember the garden gloves required for holding a redhandheld flare and let us remember the poor gent with the burnt guts. Not to mention, staring at a red flare will cause more pain than at a 5mW red laser.

EDIT : A very quick Google showed this re: IR and green.
http://www.livescience.com/6859-cheap-green-laser-pointers-dangerous.html

There are better scientific refs or course

 

[tim_ber]

All of the laser devices discussed so far cost substantially more that £25, and a decent waterproof torch will probably do the same and be safer for the users. Of course there are also radio based devices that can help to for the straight MOB though more expensive that £25 again.

Sounds like I am undercharging then. Because my lasers are better than a torch, cree or whatever make you care to mention.

Anyway, it has been intertesting to see some of the views on here. Even more interesting to know how Odeo Flare are international now - I would like to know if they are making a profit and will have to look into it. I would not buy one.

 

[tim_ber]

No need for a mole smoke, an ordinary orange smoke flare will do nicely.

A swindlery prices though.

I just spent £99 on a few extra flares and I mean just a few.

 

[maxi77]

Many green lasers are in fact made from ! micron sources which are frequency doubled to green and yes there can be residual 1 micron radiation which needs to be filtered out with a notch filter, hence the need for very stringent quality control to ensure that the source levels are not too high and there is an acceptable low 1 micron radiation level, but green light is just as dangerous as 1 micron, this is why proper quality management is needed throughout the process.

Lasers are potentially dangerous as are pyrotechnics, which is why there is a lot of safety legislation around their manufacture, sales, use etc

I am not against the use of lasers in this way but until there are proper recognisable standards they will not be easily accepted. Go right back to my point how does the rescue pilot know, and I mean really know because it is his life and livelihood that is at risk that your laser when it is used by some one in dire need of help is safe for him to fly towards.

 

[LadyInBed]

I have been giving the laser flare some thought as alternative to pyrotechnic flares.
The idea seems good, I envisage its use for when someone is looking for me, maybe after I have activated my PLB. At the moment I carry a strobe light so rescuers might find me in the dark but the laser flare might be seen further away and when there are waves obscuring line of sight.

 

[tim_ber]

Many green lasers are in fact made from ! micron sources which are frequency doubled to green and yes there can be residual 1 micron radiation which needs to be filtered out with a notch filter, hence the need for very stringent quality control to ensure that the source levels are not too high and there is an acceptable low 1 micron radiation level, but green light is just as dangerous as 1 micron, this is why proper quality management is needed throughout the process.

Lasers are potentially dangerous as are pyrotechnics, which is why there is a lot of safety legislation around their manufacture, sales, use etc

I am not against the use of lasers in this way but until there are proper recognisable standards they will not be easily accepted. Go right back to my point how does the rescue pilot know, and I mean really know because it is his life and livelihood that is at risk that your laser when it is used by some one in dire need of help is safe for him to fly towards.

Yes, as I said in post no. 7 I agree with you about the pilot bit. More research / discussions / education and international agreement needed - fat chance eh? We can't even stop shooting each other yet after how many years of population of this planet?

 

[tim_ber]

I have been giving the laser flare some thought as alternative to pyrotechnic flares.
The idea seems good, I envisage its use for when someone is looking for me, maybe after I have activated my PLB. At the moment I carry a strobe light so rescuers might find me in the dark but the laser flare might be seen further away and when there are waves obscuring line of sight.

Absolutely spot on. But I'd sport £25 over $99 (minimum) or £150 Odeo Flare that won't even fit in my pocket.

 

[maxi77]

Yes, as I said in post no. 7 I agree with you about the pilot bit. More research / discussions / education and international agreement needed - fat chance eh? We can't even stop shooting each other yet after how many years of population of this planet?

The pilot bit is pretty fundamental and just shrugging your shoulders and saying too difficult is not going to get us anywhere. The other fundamental point is that unless the observer recognises the laser as a distress signal it is pretty useless. International acceptance is a balls aching process, been there got the tea shirt, but it is the only way forward