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Documented Pilot Injury

LSRFAQ

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So it begins........

An injured pilot shows up at the right hospital with a sophisticated retinal scanner... Now the community has to deal with documented evidence of retinal damage in flight...

The @ sign in laser is because the pilot forum I copied this from bans the use of "laser" because of adwords, causing pointer adverts to appear on a flying forum.

pointer/not pointer, either way this is serious.

I snipped some speculation by a un-attributed "expert" about a very high power laser being used. I'm not buying claims of in excess of three hundred watts being responsible for this exposure.

Facts: A pilot showed up at a hospital with a discolored and damaged or inflamed section of the retina that could only result from a laser burn.

Everything else is speculation till I or someone else gets a copy of the referenced paper...

Steve



Quote:


From laserpointersafety.com

UK: Medical report on commercial pilot injured by blue l@ser at 1300 feet
Jan 24 2016
The journal Aerospace Medicine and Human Performance has published a paper entitled “Blue l@ser Induced Retinal Injury in a Commercial Pilot at 1300 ft”. The case report is as follows:

“An airline pilot presented to our department complaining of a blind spot in the upper left area of his visual field in the right eye (right supero-nasal scotoma) following exposure to a l@ser beam while performing a landing maneuver of a commercial aircraft. At around 1300 ft (396 m), a blue l@ser beam from the ground directly entered his right eye, with immediate flash blindness and pain. Spectral domain ocular coherence tomography highlighted a localized area of photoreceptor disruption corresponding to a well demarcated area of hypofluorescence on fundus autofluorescence, representing a focal outer retinal l@ser injury. Fundus examination a fortnight later revealed a clinically identifiable lesion in the pilot’s right eye commensurate with a retinal-laser burn.”

The paper said the pilot’s symptoms “fully resolved 2 wk later” and that there was no “deficit in visual function.”

The l@ser exposure happened at a “busy international airport within the United Kingdom.” According to the authors, “To the best of our knowledge this is the first documented case report of a likely retinal l@ser injury to a pilot during flight from a l@ser on the ground.” They believe the blue l@ser had a “radiant power of several watts and potentially could have led to permanent loss of central vision in the pilot’s right eye had the fovea, the area of retina responsible for high acuity vision, been involved.”

The case was first publicly announced November 23 2015 by the general secretary of the British Air Line Pilot’s Association (BALPA). He said it occurred in the spring of 2015.

From Aerospace Medicine and Human Performance, Vol. 87, No. 1, January 2016. Full text available here for purchase. Gosling DB, O’Hagan JB, Quhill FM. Blue l@ser induced retinal injury in a commercial pilot at 1300 ft. Aerosp Med Hum Perform. 2016; 87(1):69–70.

Analysis from LaserPointerSafety.com

Summary - What was the l@ser’s power?

Based on the data provided, it would have taken an exceptionally strong l@ser to even have a 50/50 chance of causing an eye injury at 1300 ft. We calculate such a l@ser would be well over 5 watts and possibly 30 or more watts. This is a conservative estimate. It assumes the l@ser and eye were not moving fast relative to each other — unlikely for a handheld l@ser aimed at a moving aircraft. It also assumes a relatively tight beam, and that the l@ser-to-aircraft distance was 1300 ft when it may well have been longer.

As of 2015, the highest power handheld visible l@sers sold on the Internet are roughly 3 watts. Sometimes handheld l@sers are advertised with greater powers, such as 5 or 10 watts, but the claimed power may be grossly incorrect. For example, in 2014 LaserPointerSafety.com purchased a “5 watt” handheld l@ser that was actually about 50 milliwatts, or 1/100th of the claimed power.

We believe one of the following scenarios is what happened:
1) The injury was a very unlucky one; the pilot just happened to experience a statistically unlikely injury that could be caused by a relatively low 3-5 watt handheld consumer l@ser
2) A higher powered l@ser in the range 5 to 30+ watts was used, possibly not handheld (e.g., an AC-powered general purpose l@ser). If so, this may have been a deliberate attempt to cause damage.
3) The injury, or change to the retina, was less damaging (not as serious) compared to the injuries used to determine basic l@ser safety concepts such as the Maximum Permissible Exposure and the Nominal Ocular Hazard distance. The doctors were able to detect subtle retinal changes that, under previous MPE/NOHD studies, might not even be perceived as injuries or damage.

Detailed analysis

The report is not clear on whether the aircraft altitude was 1300 ft, or whether the l@ser-to-aircraft distance was calculated to be 1300 ft. If the former, there would be an additional horizontal distance so the l@ser could enter the cockpit window (e.g., it did not come 1300 ft straight up through the bottom of the aircraft).

For purposes of this discussion we will be conservative and say the l@ser-to-aircraft distance was 1300 ft.

One of the best-known consumer handheld blue l@sers is the Wicked l@sers S3 Arctic, introduced in 2010. It is called a “1-watt” l@ser but has an actual output around 750 milliwatts (3/4 watt). The Nominal Ocular Hazard Distance of this l@ser, with a 1 milliradian divergence, is 635 feet. This means that beyond 635 feet, there is a “vanishingly small” chance of l@ser exposure causing a minimally detectable change to the eye, under laboratory conditions when the eye and the l@ser are held in fixed positions relative to each other.

So a S3 Arctic could not have caused the injury at 1300 ft. This is more than twice the “safe” NOHD distance.

A more powerful l@ser with an output of 3.1 watts and 1 mrad divergence would have an NOHD of 1291 ft. It is possible that an exposure from a 3.1 watt l@ser could have caused an injury, when the eye and the l@ser are held in fixed positions relative to each other.

However, note that the NOHD has a built-in “reduction factor” or “safety factor”. This means that the chance of injury, if someone is at or just within the NOHD, is still very, very small.

At roughly 1/3 of the NOHD, the chance of injury increases to 50%. Specifically, at 0.316 times the NOHD, there is a 50/50 chance of a l@ser exposure causing a minimally detectable change to the eye, under laboratory conditions when the eye and l@ser are held in fixed positions relative to each other. So what we are looking for is the power of a l@ser that has an NOHD of 4108 ft. (This is because 1300 ft would be at the 0.316x “50/50” point.)

A l@ser with an output of 32 watts and 1 mrad divergence fits this. That means there is a 50/50 chance that a 32 watt/1 mrad l@ser exposure under laboratory conditions could have caused a minimally detectable injury to an eye that is 1300 ft. away.

If the divergence was less — a tighter beam — then the overall l@ser power could be lower as well. This is because a tighter beam will have greater power density at a distance than the same power spread out in a wider beam. Note however, that the higher the power output of a l@ser, the harder it is to make a tight beam. Adding a focusing lens on the front of the l@ser is not significant at long distances. So it is likely that a multi-watt relatively inexpensive consumer l@ser would have a beam of 1 milliradian divergence or wider.

At 8 watts and a tight 0.5 mrad divergence, there would be a 50/50 chance that a l@ser exposure under laboratory conditions could have caused a minimally detectable injury to an eye that is 1300 ft. away. Again, 8 watts at 0.5 mrad is exceptionally tight for a consumer l@ser.

Second analysis

LaserPointerSafety.com received a note from a l@ser safety expert who read the above.

This person wrote “Some of the more important factors are that the aircraft is obviously not stationary, and that the 1300 foot range (as a minimum) is still a very distant target. There is doubtless attenuation in the windscreen, so this even without considering the ED50, for this exposure to turn into a definite injury is highly improbable.”

The expert’s “best guess” was that the exposure was 2-3 orders of magnitude above the MPE “to hope to overcome the ameliorating factors (movement, windscreen, atmospheric effects, etc).” This means that the exposure was 100 to 1000 times above the Maximum Permissible Exposure. Recall that the MPE is the highest irradiance at which injury is unlikely. For a 1/4 second exposure that would be 2.54 milliwatts per square centimeter. So the expert’s best guess is that the actual irradiance, to cause the stated injury, would be around 254 to 2540 mW/cm².

Earlier we established that a l@ser with an output of 3.1 watts and 1 mrad divergence would have an NOHD of 1291. Another way of saying this is that a 3.1 watt, 1 mrad l@ser beam would be just at the Maximum Permissible Exposure, at the aircraft windscreen.

"

End Quote

Steve
 
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Jeffrey T

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Wow this sucks! We don't need this type of negative exposure. But...it is indeed interesting to read.

No matter what happened, I'm glad that the pilot had no permanent damage.
 

BoskoSLO

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That's why we can't have nice things. You can be only be so smart but for stupidity... there is no bottom (talking about people who point lasers at other people of course). I can't imagine how it must feel to be blind and I hope I never will be.
 
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InfinitusEquitas

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Can't say I'm at all surprised, except that it took so long for something like this to happen.

Glad the injury sustained was only temporary.

Does seem unlikely that this was accidental, or done with a common handheld laser pointer.
 

Laser Chick

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I am not a violent person but if I ever saw a person target an aircraft, vehicle or do something dangerous/stupid with a laser on purpose. I would so want to punch them right in the throat or at the last grab the laser from them and not give it back or smash it on the ground. I know that "I have no right to do that" but if they are purposely using a laser to do harm I certainly would do something.
 

Jeffrey T

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I am not a violent person but if I ever saw a person target an aircraft, vehicle or do something dangerous/stupid with a laser on purpose. I would so want to punch them right in the throat or at the last grab the laser from them and not give it back or smash it on the ground. I know that "I have no right to do that" but if they are purposely using a laser to do harm I certainly would do something.
I hear ya!

I was chatting with someone recently, and mentioned that I actually can understand accidentally, quickly hitting a high-altitude airplane in some cases. I know.....this sounds terrible. But, some airplanes at very high altitude cannot be heard, are nearly indistinguishable from stars in a clear sky, and can barely be seen. Someone simply shining a laser into the sky, whether to point out stars, or just for beauty, could easily jet a beam at a plane.

HOWEVER.....these are not the issues making headlines. These are idiots intentionally trying to tag aircraft, and in many cases intentionally tagging the cockpit.

What the heck!!?? :scowl:

-jeff
 

hakzaw1

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I would get my satisfaction via the $10K (some say its $20K) reward..

may have skimmed over the above --but

anyone mention the, however remote
possibility that the pilots own eye's played a factor in this--

If I had kids in school I would for sure be asking what they are NOW teaching about lasers-- we need positive peer pressure -- only way to prevent more of this..

hate to think it but.. could have been some kind of terrorists thing..
 
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LSRFAQ

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If the pilot was wearing glasses, for a quick approximation, the increased collection ratio is 50 mm / 7 mm = ~7 times more energy at the retina. 50 mm is the standard number used for the diameter of eye glasses or binoculars in certain laser safety calculations. Ouch...

Steve
 

Jeffrey T

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If the pilot was wearing glasses, for a quick approximation, the increased collection ratio is 50 mm / 7 mm = ~7 times more energy at the retina. 50 mm is the standard number used for the diameter of eye glasses or binoculars in certain laser safety calculations. Ouch...

Steve
Wow LSRFAQ....I had thought about that, and apparently neither did the authors of the article / analysis. Very good (and interesting) info!

-jeff
 

Lifetime17

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I am not a violent person but if I ever saw a person target an aircraft, vehicle or do something dangerous/stupid with a laser on purpose. I would so want to punch them right in the throat or at the last grab the laser from them and not give it back or smash it on the ground. I know that "I have no right to do that" but if they are purposely using a laser to do harm I certainly would do something.
Hi L Chick wow now i really fear the scorn of a woman LOL !!
Yes indeed we have to put up with idiots around us but we can only make it better with safety practices. But many will still be ignorant the the fact. We can't help some one who don't want to be helped.

Rich:)
 

hakzaw1

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I can be a real dick when some ask to handle one of my lasers-as I take out the batteries OR if it has a key I lock the laser to be 'unarmed'- when asked why... my reply is 'just like a gun' I will ONLY let you handle it when it is un-armed/unloaded-

ONLY if they will go by my rules will they handle it armed.....

my 'toys'--- my rules-

hak
 

J4K3ST3R

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I can be a real dick when some ask to handle one of my lasers-as I take out the batteries OR if it has a key I lock the laser to be 'unarmed'- when asked why... my reply is 'just like a gun' I will ONLY let you handle it when it is un-armed/unloaded-

ONLY if they will go by my rules will they handle it armed.....

my 'toys'--- my rules-

hak
I am the same way. Had a buddy wanting to hold my Arctic the other day.
Told him you can hold it but that's all. Pestered me about wanting to just shine it into the sky, but was a repeated no from me.
Handed it to him turned off, and he fumbled around trying to be sneaky and turn it on.
He got chewed out from me, and was butthurt the rest of the night.
If he wants to shine a beam to the stars he can buy his own laser.
Is what it is
 

pmurph5

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If the pilot was wearing glasses, for a quick approximation, the increased collection ratio is 50 mm / 7 mm = ~7 times more energy at the retina. 50 mm is the standard number used for the diameter of eye glasses or binoculars in certain laser safety calculations. Ouch...

Steve
Steve, 2 things...

1) I have never heard of eyeglasses being considered as a factor that increases the laser's collection power. Binoculars and telescopes, yes. But thinking about how regular light is focused by glasses -- it is not all collected and focused down onto one bright spot on the retina! If you need more info, check with Greg Makhov. Greg also has done an analysis indicating that even binoculars don't have the collection/focusing ability that U.S. regs say they do.

2) Since the version of the article you posted to start this thread, I have gotten additional information about the pilot who claims to have been injured by a laser. This info came from a source with direct access to the detailed documentation on this case. He said he “doesn’t believe it was laser-induced” and that the injury being caused by a laser was “not confirmed, despite what the journal paper says.” In addition, there are some other peculiar things about this case, such as the long lead time in this being made public, in the pilot remaining unknown and not speaking out, and in the pilot's claimed injury being the basis for an employment dispute between the pilot and the airline.
 




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