I was once blinded by my best friend while flying at night. He was trying to help me read a map. We were out of KDAL, heading to KSMO.
Inbound to KSMO, at night, over California’s high desert, the earth below looked black as pitch, the sky above a planetarium ceiling’s worth of stars. I’d purposely kept cockpit lighting low to preserve my night vision.
When ATC descended us from12,000 to 8,000, I dropped my sectional. Thinking he was being helpful, my non-pilot friend saw this as an opportunity to show off the new, high-intensity headband flashlight he’d brought along, the kind intended for caves, not cockpits.
“Check this out!” he said. I turned toward him just as he flicked on the flashlight.
“AHHH!” I screamed and jerked away, but not before being blinded completely. My twitchy reaction threw us around the sky and in the cockpit, too. That’s when he realized his mistake. Thankfully, some of my left eye’s vision came back soon enough.
Those were some tense moments in the cockpit. Scanning the six-pack of IFR instruments with one marginal eye was grueling work. We were already on the Fernando Arrival inside Avenal. By the time we got to PIRU, I knew I was in no condition to fly a non-precision approach, the only kind available at KSMO.
I declared an emergency and told ATC I needed to divert to KVNY for one of its ILS 16 approaches. I held over Fillmore and set up for an ILS 16R. ATC vectored me from there in shallow turns outside of Umber for the intercept.
Thank goodness for late night calm winds over Southern California. We came down the approach like the airplane was on rails. Still, I thumped the landing.
I was lucky. Within three hours, my eyesight had completely returned. In researching “bright lights in the cockpit,” I came across several reports to NASA’s Aviation Safety Reporting System where pilots were struck in the eyes by lasers and suffered much worse effects.
In one case a pilot witnessed lasers “being fired” roughly three miles from his aircraft position during the approach phase of flight. His captain instructed him to stay on the instruments and avoid looking at the lasers. The captain reported the lasers to Tower.
Tower asked the crew to gauge the distance of the lasers’ location from the runway. So the flying pilot got off his instruments and looked for the lasers to verify their location. At that point, the lasers fired at the aircraft and hit the cockpit.
The pilot wrote: “I felt a flash in the cockpit but did not feel that it had affected me. We landed the airplane safely. While taxiing, I began to feel a slight pain and itching in my left eye. I discussed it with the captain and felt that I had sustained some trauma to my eye. An eye specialist reported no permanent damage to the eye, but suggested I rest it for five days. As of this report, I am still experiencing pain and light sensitivity in my left eye.”
On the one hand, non-laser artificial light — like from a flashlight — can temporarily blind, but not damage, the eye by overwhelming the photoreceptors. Photoreceptors help us process light. Overwhelmed, they shut down momentarily. Usually, unless they are actually burned by intense light at close range, the photoreceptors will recover.
A laser beam, however, differs from other sources of light in that it emits light coherently. In physics terms, that means a laser can be focused to a tight spot, enabling applications such as laser cutting and lithography. So a laser can easily and permanently damage the eye, resulting in vision alteration or total blindness. In fact, a 50 mW laser pointer or stronger will burn or explode human tissue. Pupil contraction or snapping your eyelids shut in defense are about as effective as holding your hand up to stop a bullet.
Laser strikes against pilots and aircraft are not limited to low altitude approaches either. A laser’s cohesive property allows the beam to stay narrow over great distances. One flight crew experienced laser tagging at 36,000 feet.
A member of that flight crew wrote in his NASA report: “The captain was looking out of the left cockpit side window at the moment I saw a flash and asked me if I saw it. I informed him that I only saw the reflection. We were in visual meteorological conditions, on top of a layer of very thin cirrus in dark conditions. The cockpit lights were off with very low integral instrument lighting. After several minutes, the captain complained of less than clear vision but nothing ‘too serious.’
“During the remaining flight, the captain complained of sensitivity in his eyes, particularly the right eye, while also stating that his vision seemed to be OK. We landed on Runway 14R at KORD approximately 50 minutes later. Once on the gate, it was obvious that the captain’s eyes were extremely bloodshot with what appeared to have been blistering and possible bleeding at the inside corner of his right eye.
“The captain was then complaining of increased discomfort in both eyes and blurred vision in the right eye. During the parking maneuver, it was necessary to aim the cockpit towards fluorescent lights on the terminal building. These white lights caused the captain significant discomfort. I accompanied the captain to the hospital near the airport so that a physician could examine his eyes.”
A former military physician examined the captain’s eyes at the emergency room. He verified damage to the exterior of the captain’s eyes. While the retina was not damaged, his normal 20-15 vision was temporarily reduced to 20-60.
In a follow-up interview, it was determined that the FBI contacted the captain about this event. The light appeared to have a greenish white hue emanating at or near the aircraft’s flight altitude. It’s possible that the laser was fired from the ground or from the passenger compartment of a passing airplane. Scary.
If polled today, many pilots might say that drones pose the greatest safety threat to pilots, passengers and aircraft. Until I researched this topic, I would have agreed. Not anymore. I would argue that the greatest single threat to aviation today is the proliferation of lasers.
A 5 mW is the U.S. legal limit for laser pointers. Even so, portable lasers of 500-600 mW are available via the Internet. 500 mW is enough power to set paper on fire, pop balloons and cause potential burn-in on wood. Right now those lasers are used for government-approved applications in astronomy research, and they cost a bundle — $1,500 to $2,500.
But “the cool factor” of these lasers cannot be understated. Like drones and computers before them, their prices will fall as their power increases. As such, lasers will continue to gain popularity and availability as recreational devices. What’s more, these portable lasers are powered by lithium batteries and are the size of a small flashlight. That makes them easy to deploy, easy to move, and easy to hide.
What can we do to protect ourselves? Laser goggles do exist. Wearing them could protect a pilot during an attack, but only if the pilot is wearing the right pair. Unlike sunglasses, which can protect from UV rays across all colors in the visible light spectrum, laser goggles can’t.
Lasers emit light in one color. Laser goggles transmit light — in other words, they block specific colors of the spectrum while letting other colors pass through. Laser protection involves purchasing goggles that are the color farthest from the offending laser beam. Blue-violet goggles would protect against red laser light. Red laser goggles would not. A red laser would pass straight through. The point is that you’d have to buy, and simultaneously wear, a pair for every possible laser beam color to be fully protected. Impractical.
Lasers are a significant enough hazard that the U.S. Air Force is studying laser encounters as a potential national security threat. Its National Air and Space Intelligence Center (NASIC) currently collects information related to laser incidents, both military and civil.
According to NASIC’s Public Affairs Office, civil aviation pilots are encouraged to report incidents directly to the local FSDO, another way to protect ourselves. The laser reports will be captured by the FAA and sent to NASIC.
Right now, while GA lobbyists weigh in on drones and the threat they pose to bring down aircraft, pilots are being injured by laser attacks. Right now lasers pose a greater threat to aviation safety than drones. A drone has yet to take out an aircraft. Lasers have already incapacitated several pilots.
The significant rise in laser reports by pilots should raise concerns about the increased likelihood of both members of a two-person crew, or a solo pilot, getting blinded by a laser and the possibility of real damage to the general community and the GA community, too.
Let’s make some noise before we all get fried.
The U.S. Navy some years ago found that for Carrier Flight Deck operations going from dim red lighting for the supposed sake of “preserving night vision” to white flood lighting was far safer than the previous reliance on dim red lightning which had been used for so long including pilot’s night vision adapting in red lit ready rooms before going up to the flight deck. That seemed to be causing more problems than it was preventing. So what did they do? They dispensed with red lighting below decks and turned up the white flood lighting on the flight deck. Result – less collisions and less hazards for pilots and flight deck personnel. Catapult launches proved there was no difficulty transitioning to instruments off the flight deck as long as the instrument lighting was turned up prior to launch. This article seems a bit exaggerated or embellished. For the pilot in the story KDAL to KSMO to have suffered such a deterioration of his night vision there had to be more going on than this article is revealing. A Laser on the other hand I agree is a whole different ball of wax. Lasers of sufficient strength are flat out dangerous for one’s vision be it day or night.
Jeff: I have some experience with the megawatt Airborne Laser http://en.wikipedia.org/wiki/Boeing_YAL-1 and its predecessors, have witnessed a few hits and a lot of misses with test machines ranging from sub-watt to megawatt. The reason the YAL-1 is in the boneyard is because atmospherics make aiming lasers a crap shoot and rapidly attenuate power. This FAA sub-watt laser demo confirms my experience http://www.pangolin.com/faa/laser-aircraft-animation-and-explanation.htm
Your first hand experience with a flashlight is telling. Were you hypoxic? Was the carbon monoxide alarm working? A little hypoxia and CO conspire to make night vision a hazard after which you would benefit from turning all the cockpit lights up and deep breathing or going on oxygen – just like a lightening strike – to get night vision back. I suspect the same goes for laser strikes.
You really need to run your article by an eye doctor, laser surgeon or someone with experience with sub-watt and lab-power lasers to understand the real hazards. Claiming a sub-watt laser is the greatest threat to aviation isn’t justified. Some of your comparisons (600mw [0.6w] can burn paper [so can a match] ) are meaningless at a slant range of several thousand feet thru humid and dusty air- coherent light or not. Startling, yes – but I bet it’s not at all like a lightning strike. Cops love LED flashlights because they have the same startling effect on a perp as a laser or strobe, plus it lights the way better. Nobody’s made a fuss about being blinded by high-power LEDs.
The likelihood of permanent physical damage from sub-watt lasers seems unlikely. But I’m not an expert. The cases you cite of red eyes are more likely from rubbing and panic than the light. If they had been burned there would be blistering and other signs. But ask a professional. Please. And review night vision physiology. Understanding it might remove the sense of urgency to land vs just hold and let night vision return. http://en.wikipedia.org/wiki/Adaptation_%28eye%29
My guess is that most laser incidents are from the side. That would affect peripheral more than central vision – already compromised at night and the first to bleach out. A review of night blindness and night vision might do more good than getting overly excited about it. After years of flying red cockpits to enhance night vision I gave because of all the problems it created and went with white light so my aged eyes can read charts AND I can still see traffic.
You might also look into why rescue laser flares are legal if the effect is so devastating. It seems odd that we prohibit shining them at aircraft yet plan to do just that in a SAR situation. http://www.greatlandlaser.com/green-rescue-laser-flare/
Having been lazed from a distance of 10nm at 5,000 feet in the radar pattern at Travis AFB, I’m going to have to say that your assumptions are incorrect. Luckily, I wasn’t looking in the direction of the flashes that illuminates our cockpit. The guy sitting next to me wasn’t so lucky. After we were grounded until we underwent a four hour eye exam that included getting our eyes dilated, he was found to have a blind spot in his vision. He had headaches for a week and was grounded for a month until his vision improved. Another pilot friend of mine was grounded for a year and almost lost his career. Whatever the milliwatts, aircrew members are having their vision seriously damaged by idiots on the ground thinking their laser isn’t powerful enough to do any damage. I’ve spent several thousand dollars on flying, not to mention the blood, sweat, and tears to get to where I am now. It only takes a literal flash of light to ruin your vision and potentially ruin your flying career forever.
Seth: I assume that if you were ‘grounded’ you were military. I was military too, and any airborne physiology event always sprang the overly bored flight surgeon’s office into overdrive. Job security and data collection I guess.
Your buddy needing his eyes dilated and they discovered a blind spot. Are you aware that every healthy eye has a blind spot?
One has to be careful about running to the flight surgeon with an owie real or imagined. Recall the passage in the ‘right Stuff’ where Sam Sheppard notes that going to see the doc is a hazard to aviators?
“The best you can hope for is to come out as good as you went in.”
So if the story isn’t embellished, the doc will sometimes do it for you.
Early in my career I learned that crewdogs that report fainting after a jog in 110F heat after flying 14 hrs from Tinker to Riyadh with a coffee IV going after leaving a pissed off wife for 30 days got a quick lesson in how poorly logic and common sense is used at times. Ditto reporting hearts that occasionally skip a beat fueled by 140 octane coffee, a sick #4 engine and no sleep. Deployed and grounded. Kill me now.
Note that the FAA medical branch is run by retired flight surgeons.
Seth said: Another pilot friend of mine was grounded for a year and almost lost his career.
[Why, Bar fight? Slip and fall at the O-club? Care to tell us the subject?]
I had a flight student who used my classroom laser to illuminate a young lady’s chest. Her partner noted the red dot and the young lady was in the process of turning the pointer into a suppository when I objected: It messes up the circuitry.
Which raises a question about laser designators on rifles and handguns. Mine are all 5mW. Cops and swat teams love them for the intimidation factor and I bet more than a few thousand eyes have been dazzled by the red dot from less than a few meters. Where is the outcry; county bills for eye docs and seeing eye dogs? I need to call my sheriff to gather data and ROE.
According to an FAA notice, permanent TFR around the White House uses laser strobes to warn aircraft. I wonder how that affects the eyes of aircrew coming and going there?
If subwatt lasers were really such effective anti-military pilot devices, one wonders why Al Queda doesn’t give one to every kid to point at aircraft?
Once again, we need to get some real data on this.
To be clear right from the beginning, I have no official qualifications. I’m certainly no doctor, and nobody should take these comments as such. I am, however, a pilot who has a lot of experience with lasers (I’ve been an enthusiast for years, owned just about everything from 5mW to 2W, and used to work for a laser company). During my time working with lasers (it’s sort of a past-hobby now), what I took most interest in was laser safety. Lasers, especially high-powered ones, can be a lot of fun, but they can be disastrous in literally less than a second. Additionally, I’ve thankfully never been hit while flying, so I don’t actually know what it’s like in the cockpit.
From my experience, I think the risk of permanent eye damage regardless of the laser power (to a point) is relatively low. As laser light continues (especially with green lasers, which happen to be the perceived brightest by our eye), the beam diverges. This means that the beam becomes wider. You may be surprised to hear that a 200mW laser can burn things when a common light bulb is 60W. This is because the light is condensed into a small beam. So, as the beam diverges, its overall danger is lessened. There’s a term in lasers called “NOHD” or Nominal Ocular Hazard Distance. This is the distance in which a laser’s light does not pose risk for eye damage for a .25 second direct exposure. For a certain 900mW 532nm/green (note the average laser you buy in a store is 5mW, 900mW is a VERY powerful laser) laser I found, the NOHD is 149 meters, or 489ft. Most likely, any exposure you would have in a cockpit is going to be much further than 489ft. That’s just one particular laser, but the percentage of laser incidents that involve a laser that powerful I would estimate are extremely low. The reason the lasers sold in stores never really exceed 5mW is because 5mW doesn’t really pose a threat from any distance. It’s still important to be careful, but if idiots are idiots, everyone will probably be okay. This is especially true from the difference from the ground to an aircraft. To be clear, this is simply referring to eye damage. I’m only saying that the chances of having permanent eye damage from a laser incident are very low.
I am not saying laser incidents are not an issue, boy are they. Laser light is extremely bright, and especially through the natural divergence of the beam, and cockpit windows diffusing the light, it could easily illuminate the cockpit with (temporarily) blinding light. People who do such a horrible thing make me so angry, since it’s such a dangerous disrespect to two of my hobbies, but it’s most important that as pilots we are prepared for such incidents. We can’t stop everyone from doing this. If it happens to you, do your best to avoid it, but make sure the airplane is your first priority, not your eyes, since as I said, permanent eye damage is unlikely. Honestly, it’s probably not a bad idea for pilots to carry a few pairs of laser safety glasses when going night flying. You need different glasses for different colors of laser light, but it’s not a bad idea. I keep a few pairs in my flight bag to cover the whole spectrum, just in case. Also, laser safety glasses are very dark, so you’re going to need sufficient light over your instruments in order to be able to see those. Reducing your visibility is obviously never good, so the best solution would be to avoid the culprit, but carrying safety glasses could save your life if you’re struggling to avoid someone shining a laser at you. Ask around: this is happening to a lot of people. Be prepared.
JT says laser is light is condensed into a small beam.
[Sort of. According to http://en.wikipedia.org/wiki/Laser Lasers are distinguished from other light sources by their coherence. Spatial coherence is typically expressed through the output being a narrow beam, which is diffraction-limited. Laser beams can be focused to very tiny spots, achieving a very high irradiance, or they can have very low divergence in order to concentrate their power at a great distance.
LED lights are LED. Subwatt laser pointers are LEDs. I’ll swear on a stack of burned out 4509 landing light bulbs that I can’t tell the difference when flash blinded by one or the other, and recovery is about the same. How does one distinguish what just flash-blinded you?