Claims inaccurate statements about lasers exaggerate threat to pilots

The recent wave of reports of US aircraft illuminated by lasers has highlighted the need for the public and safety officials to better understand laser technology, says the International Laser Display Association (ILDA), which claims a number of inaccurate statements have been repeated by government authorities and the media regarding the hazard level posed by lasers. "I'm worried that much of the reaction to date has been based on fear rather than fact," said David Lytle, ILDA Executive Director. The group represents over 100 companies, including manufacturers of laser equipment and producers of laser shows.

A joint memo by the Department of Homeland Security and FBI, for example, recently warned that terrorists might use inexpensive, off-the-shelf lasers to blind airline pilots in flight. Safety calculations performed using internationally accepted exposure levels show this is not the case. The energy necessary to cause a permanent eye injury at a distance of 1,500 meters would require an unusually high-powered laser and the use of highly specialized optics to focus the beam. "This type of equipment can cost more than $100,000 and is decidedly not off-the-shelf or easy to operate," said safety expert Greg Makhov, Chair of the ILDA Safety Committee.

Although federal authorities initially sounded a warning about terrorists, an FBI spokesman subsequently stated that the rash of recent illuminations of aircraft by lasers all involved pranks. He described the exposures as a "nuisance." An official of the Airline Pilots Association discounted the threat lasers posed to aviation, saying lasers would not be a highly effective weapon against aircraft.

High-powered entertainment laser systems are not involved in any of the recent incidents. Laser entertainment companies must inform state and federal officials of shows in advance and outdoor shows must comply with strict rules that keep laser beams away from airports. Spotters are used to monitor the skies and shut down the laser show if a plane approaches the display.

Although a New Jersey man recently confessed to aiming a laser pointer at an aircraft flying at an altitude of 3,000 feet, it would have required the combined output of several thousand of these pointers, all focused in a single beam, to cause eye damage to the pilot. The common 5.0 milliwatt laser pointer cannot cause eye damage beyond fifty feet. Even at distances of 300 feet, a pointer constitutes a hazard -- under the worst of circumstances -- similar to the glare from an oncoming car's headlights or the flash from a point-and-shoot camera. While this can impair the vision of some people, the effect is temporary and does not cause permanent damage.

A recent Federal Aviation Administration analysis of 150 incidents involving lasers that illuminated aircraft found no cases of injuries or accidents caused by lasers. Although there have been anecdotal reports of permanent injuries suffered by pilots, there has never been a case supported by an ophthalmologic examination.

The laser display industry joins other safety officials in urging the public to never aim a laser pointer at anyone's eyes or at the operator of a vehicle. Laser pointers are visual distraction but will not cause eye damage unless a person stares directly into the beam for an extended period.

ILDA continues to study lasers and air safety and offers to work with safety authorities to further explore the issue. "Once the public and pilots better understand the nature of the technology, we think the reaction will be more proportionate to the risk," said Lytle.

FMI: www.laserist.org