Regulations Aim at Illegal Laser Activity

Aircraft illumination by handheld lasers has become a worldwide problem — in the U.S., the FBI offers a $10,000 reward for information leading to a conviction of the crime.

Up in the sky, it’s a bird, it’s a plane! No, it’s a laser beam! And illegal use of them is growing.

The hazard from these lasers is not to the aircraft frame, but to the pilot as a distraction. The distance from which these lasers present a retinal hazard makes it impractical for the operator to be present, while the intensity needed to distract a pilot is extremely low (nanowatt range).
There is a distinction between different types of such devices: a laser pointer is a handheld visible laser device that emits no more than 5 mW as a continuous wave beam. A handheld laser is any laser device that is portable and whose visible output is greater than 5 mW. Today, units from 10 up to 5000 mW are available, which is 5 W in a handheld device.

The effects defined below result from laser pointers and handheld lasers.

Glare is obscuration of an object in a person’s field of vision due to a bright light source near the same line of sight (e.g., oncoming car headlights).

Flash blindness is a visual interference effect that persists after the source of illumination has ceased.

Afterimage is a reverse contrast shadow image left in the visual field after exposure to a bright light that may persist for several minutes. 

Risks and testing

National Institute of Standards and Technology researchers have tested 122 laser pointers using a moderately low-cost apparatus designed to quickly and accurately measure the properties of handheld laser devices. They found that nearly 90 percent of green pointers and about 44 percent of red pointers tested were out of compliance with federal safety regulations.

Very little green light is required to illicit detrimental effects at night or in low-light conditions. In 2014, there were 3894 laser incidents reported to the U.S. Federal Aviation Administration (FAA) and 3960 reported in 2013.

The FAA offers a free downloadable video on its website addressing this growing problem; in particular, it explains how pilots should deal with illumination events. This includes helicopter pilots, who fly at considerably lower altitudes, often 1200 feet or closer to the ground.

The danger of illuminating a cockpit is the distraction to the pilot. Imagine you are traveling down the highway in a vehicle at a rapid speed, and now a bright light hits you. While your vision is obscured, you tend to stay straight and maybe slow down until you can see the road again. Now consider a pilot taking off or landing an aircraft; the light hits, and runway lights are blurred. The pilot’s reaction might be to divert the path or turn over to the other pilot, if applicable. It should be noted that changing the flight path could not only endanger the plane but any others in the zone. Diverting the course of a helicopter could present its own problems, such as hitting a nearby power line or building. 

The overwhelming majority of handheld lasers are manufactured outside the U.S. Random testing of units has shown questionable quality control, outputs vastly different from indicated and failure to include IR filters for green lasers. The most popular laser unit involved in these events is the green 532-nm laser; it is a great deal of technology in one’s hand. For example, a frequency-doubled Nd:YAG laser system comprises a 808-nm diode pump and Nd:YAG (or Nd:YLF) crystal, generating a 1064-nm beam going through a nonlinear crystal, yielding a bright 532-nm beam and focusing optics. If an IR filter has not been put in place, there is nothing to block the residual 808-nm and 1064-nm beams from exiting.

To the user operating the laser, the beam may seem to end at 1200 feet from its point of origin. The beam that is visible to the user is scattered light from dust and other particles in the air. This layer of dust and aerosols sits close the ground, and once the beam exits that boundary layer, it continues on until it hits something. For example, a 5-mW laser pointer is a distraction hazard to pilots from over two miles away. Some higher output systems can cause serious glare at such distances, while the distraction hazard is 22 miles. The beam will not be consistently on target, but random flashing is commonly reported. 

In 2013, there were 74 incidents in which law enforcement action was necessary, and there were 11 prosecutions (including two at the federal level and one at the state level).

Such activity — exposing planes or helicopters to laser radiation — is a violation of federal law, as well as those in many individual states. Motives behind these acts remain unclear.

U.S. national laws, including FDA/CDRH: 21 CFR 1040.10/11, assert that it is illegal to aim laser pointer beams at aircraft or its flight path. Many states have enacted similar supplemental laws of their own. In Illinois, for example, all Class 3B and Class 4 lasers must be registered; it is a criminal offense to “discharge into cockpits.” In Maryland, it is a misdemeanor to knowingly aim a laser at any aircraft.

Safety and prevention

Laser-protective eyewear is recommended for pilots, beyond ordinary sun or “blue blocker” glasses. Blue blocker glasses have an effect on many different colors of blue and green, which may adversely impact how cockpit instruments and airport lights are perceived. Eyewear such as Laser-Gard from Sperian/Honeywell, LaserShields from NoIR Laser Co., Laser Armor from Night Flight Concepts and LaseReflect Aviator from Iridian Spectral Technologies are among available options. 

While eyewear designed specifically for pilots can be useful, it does not block out all visible laser wavelengths. Some pilots may believe the chance of being illuminated is small and so they opt not to wear eyewear, especially if they know what steps to take if something like that happens: turn up cockpit lights, turn on auto pilot, look away and do not touch their eyes, as there is potential to scratch the cornea.