Blinded by the Light

A Look at Cockpit Laser Illumination Events

Tom Hoffmann
Reprinted with permission from FAA Aviation News

It’s one of those rare summer nights. The sky is endlessly clear and smooth as glass. Below you, the endless patchwork of tiny yellow, white, and red lights sparkle like jewels against the black velvet darkness. You treasure this moment of freedom, flying miles above all the traffic, noise, and chaos; your only companions the familiar drone of your 172’s engine and the warm glow of your instrument panel. Reducing power on final, you marvel at the perfect uniformity of the runway lights ahead as you prepare to call an end to this memorable flight.

Then, it happens. A blinding green light envelops the cockpit and startles you—as if someone sounded an air horn inches from your ear. What had been a smooth controlled approach becomes an erratic, over-controlled struggle to maintain airspeed and glide path. As your eyesight slowly returns to normal, it dawns on you—you’ve been “lased.”

A lasing event, otherwise known as a laser illumination event, is becoming a more familiar occurrence for pilots. In 2008, there were 955 reported laser events across the United States, more than triple the number in 2005. Does this increase mean you should rush out and get a set of the latest anti-laser goggles? Not likely. Nor does it mean you’ll need to equip your aircraft with photon-torpedo technology to retaliate against enemy fire from reckless laser pointer users. Yet, there are some key points to remember to help keep you safe during a laser illumination event.

Lasers 101

We often overlook the value laser technology can have in everyday life. It plays a vital role in your ability to do many routine tasks, such as watch DVD movies, secure your home from intruders, improve your eyesight, or even to get rid of that unsightly butterfly tattoo. Despite their various practical and scientific uses, lasers can be dangerous and improper use can pose a serious threat to aviation safety.

The word “laser” actually contains its own definition. It is an acronym for Light Amplification by Stimulated Emission of Radiation. Simply stated, a laser is an optical device that produces a highly concentrated beam of single-color light. A special optical amplification process known as stimulated emission transforms energy inside the laser into synchronized, narrow light waves within a low-divergence beam. In contrast, an average flashlight or light bulb emits multiple-wavelength light in several directions and becomes greatly diluted.

Lasers first gained attention in the aviation community in the 1990s, when several pilots reported incidents of illumination near public amusement events or attractions. This prompted FAA to provide greater support for outdoor laser operations in the National Airspace System (NAS) by establishing flight-safe exposure limits for lasers near airports. These standards successfully decreased the number of reported laser illumination events, and ensured pilots would be protected from lasers that could cause ocular damage.

“Once better guidelines were established, reported incidents with organized outdoor laser events declined,” states FAA Air Traffic Control Specialist and Outdoor Laser Operations Lead Kelly Neubecker. “Although providing information is voluntary, organized laser operators have a vested interest in maintaining their displays responsibly and actively seek the proper approval.”

To validate the effectiveness of these new guidelines, FAA began closer monitoring of laser illumination events and saw a decline for several more years. Then, something peculiar happened. In late 2004, an unusual spike in incidents occurred that was linked to a new source of laser danger—handheld laser pointers. The correlation was clear as it was about this same time when green laser pointers, generally used by presenters or by astronomers to point out celestial objects, became inexpensive and widely available. Also of concern was the color of these pointers, as green lasers produce a beam near the eye’s peak sensitivity, which means that they are perceived as many times brighter than a similarly powered red laser.

“Although the power produced in most laser pointers is usually not enough to cause physical eye damage, the operational problems caused by distraction or the resulting ‘visual effects’ can have serious consequences, especially during a critical phase of flight,” says FAA Vision Research Team Coordinator Dr. Van Nakagawara.

Operational Concerns Put to the Test

FAA performed studies at its test facility in Oklahoma City and validated the operational concerns of a laser attack. The studies exposed 34 pilot test subjects to varying intensities of laser illumination while performing approach, landing, and takeoff maneuvers in a full-motion aircraft simulator. While illuminations at a lower intensity were regarded as more or less a nuisance, those at a higher intensity resulted in many visual and operational problems for the pilots. Figure 1 shows photographs of the different levels of visual effect hazards, similar to what these pilots witnessed during the simulator test.

These effects during laser events have also been documented in pilot reports, where aviators have described losing sight of the runway, flaring too early, or executing a missed approach.

These events can be much more challenging for a general aviation pilot who often flies slower, lower, and has no other pilot to take the controls. Even more at risk are helicopter crews, due to their close ground proximity and a helicopter’s tendency to present a more stationary target by hovering.

The three visual effects that could impact pilot operations during a laser illumination are:

• Flash blindness – A temporary visual • interference effect that persists after being “lased,” similar to a bright camera flash.
• Afterimage – A distracting shadow image left • in the visual field after exposure to a bright light that can last for several minutes.
• Glare – An object in a person’s field of vision • being obscured due to a bright light source near the same line of sight.

“The severity of these visual effects can vary greatly among pilots,” says Dr. Nakagawara. “Factors such as age and existing eye condition can prolong the recovery time for normal vision after a laser event. Some pilots can even experience a temporary total loss of vision.”

Dr. Nakagawara and his team at the Civil Aerospace Medical Institute (CAMI) in Oklahoma City keep a close watch on laser events nationwide and report regularly on any notable trends. Dr. Nakagawara also participates in several industry and government groups, including the American National Standards Institute (ANSI) and the SAE G10T (Laser Safety Hazards) Subcommittee, the latter of which he chairs. Dr. Nakagawara’s experience with these groups helps keep the Vision Research Team abreast of changes and proactive with new developments in the laser industry.

Integral to the success of the Vision Research Team is the data it receives from various laser-incident reporting mechanisms. Before Advisory Circular (AC) 70-2, which standardized the reporting procedure for laser events, reports were often vague with inconsistent findings. Since the AC’s issuance, however, more than 2,600 laser events have been reported to ATC and FAA System Operations, a 270 percent annual increase since 2005. It is unclear whether these numbers reflect a genuine increase or a heightened awareness of the need to report these events.

According to FAA Operations and Air Traffic Control Specialist Cornelius Moore, it’s both. “Since AC 70-2, the number of reports has increased dramatically,” says Moore, whose responsibilities include providing a weekly laser-event report to several government agencies and stakeholders, including FAA’s Vision Research Team. “In conjunction with the AC, the growing popularity of high-powered, low-cost laser pointers in the market makes laser events an even greater possibility.”

Pointers - What if I Get “Lased?”

If you encounter a laser illumination event during flight, here are a few pointers:

• ANC – Remember to Aviate, Navigate, and Communicate.
• Alert a crewmember – If you’re flying with another pilot, advise him or her of the laser and determine if the other pilot is safe to assume control of the aircraft.
• Interrupt the light – Use a clipboard, visor, or your hand to block the light if possible. Sometimes you can maneuver and use the aircraft to block the light.
• Turn up the cockpit lights – Light-adapted eyes are less prone to the effects of a laser.
• Advise ATC or broadcast on appropriate UNICOM frequency – Be sure to include aircraft call sign and type; altitude and heading; the color, direction, and location of the laser; the length of exposure; and any injuries sustained.
• Resist the urge to rub your eyes - This can irritate the eyes more and cause tearing or a corneal abrasion. If you are concerned or if you feel you have suffered any eye damage - Have your eyes examined.

A pilot is typically the last line of defense in preventing a laser illumination from becoming a serious accident. “The key to successful mitigation of future events is to report them as quickly and accurately as possible,” states Moore, who also has an active role in improving FAA’s data collection efforts for laser events. Among those developments are a new e-mail address (LaserReports@faa.gov), a fax number (202-267-5289), and soon a Web-based form to facilitate input for pilots and ATC.

“Despite all the methods of reporting, the best way for us to get information is for pilots to report the incident directly to ATC,” adds Moore. “This allows us to take immediate action and increases the likelihood of local law enforcement making a speedy apprehension.”

Reporting a laser illumination to ATC also has other benefits, as it triggers a general caution warning broadcast on all appropriate frequencies every five minutes for 20 minutes and is included in ATIS broadcasts for one hour after the report. The following is an example of a laser-related ATIS report:

UNAUTHORIZED LASER ILLUMINATION EVENT, AT 0100z, 8 MILE FINAL RUNWAY 18R AT 3,000 FEET, GREEN LASER FROM THE SOUTHWEST.

The Future of Lasers

There are many exciting prospects for laser technology, including deep-space data communications and computers that can process at the speed of light. Despite the dangers of “rogue” unauthorized users, lasers may hold the key to a whole new level of aviation safety. Lasers are already being successfully used to warn aircraft that violate the DC Special Flight Rules Area (SFRA) and could be used as a bird-strike deterrent, as well as to prevent runway incursions.

The key to a safe flying environment is to keep both pilots and laser operators informed and educated. Operators need to understand the dangers caused by careless actions with a laser. And, for pilots, knowing how to recognize, react, and report a laser event is the best way to keep the skies safe now and in the future.

Tom Hoffmann is associate editor of FAA Aviation News. He is a private pilot and holds an Airframe and Power plant certificate.