'Don't Beam Me, Scottie!'
ALPA pilot safety representatives and staff have been working in several ways to minimize pilots' exposure to, and risk from, laser illuminations of cockpits.
By Jan W. Steenblik, Technical Editor
Air Line Pilot, March 2005, p.14
A laser illuminating an aircraft cockpit can cause flightcrew members to suffer temporary vision loss associated with (1) flash-blindness (visual interference that persists after the source of illumination has been removed), (2) after-image (a transient image left in the visual field after exposure to a bright light), and (3) glare (obscuration of an object in a person's field of vision caused by a bright light source near the same line of sight).
ALPA Recommendations for Flight Crews
If a laser beam illuminates a flightcrew member in flight, the crew should follow these procedures:
Please contact the ALPA Engineering and Air Safety Department at 1-800-424-2470 with questions or comments.
These recommendations were included in ALPA operations Bulletin 2005-01, Laser Illumination Hazards, issued January 14 jointly by Capt. Stephen Luckey, chairman of ALPA's National Security Committee; Capt. Bernie Sanders, chairman of ALPA's Human Performance Committee; and Capt. Terry McVenes, ALPA Executive Air Safety Chairman.
Laser effects on pilots occur in four stages of increasing seriousness-distraction, disruption, disorientation, and incapacitation. The potential for a laser illuminating a cockpit to cause an aviation accident definitely exists; however, the fact that no laser-related aviation accidents have occurred to date shows that the hazard can be managed successfully.
Lasers are not a new threat to aviation. The rapid proliferation of visible laser beams has resulted in a multitude of documented cases of lasers illuminating flight crews since the early 1990s. Since then, ALPA's efforts to locate and address potential laser threats have intensified. An incident involving an outdoor laser light display in Las Vegas in October 1995 added impetus to those efforts.
Hundreds of incidents have occurred since then. Twenty occurred between Dec. 23, 2004, and Jan. 2, 2005, alone, including recent events reported in Colorado Springs, Cleveland, and New Jersey. Federal authorities recently filed widely publicized charges against a Parsippany, N.J., man for shining a laser pointer at a private airplane and temporarily blinding two pilots during their approach to Teterboro Airport.
In response to these recent incidents of unauthorized illumination of aircraft by lasers, on Jan. 11, 2005, the FAA issued Advisory Circular (AC) 70-2, Reporting of Laser Illumination of Aircraft. The AC requires all pilots to immediately report any laser sightings to air traffic controllers.
The controllers, in turn, must share that information through the federal Domestic Events Network (DEN), a telephone bridge that safety, security, and law enforcement personnel monitor constantly. Air traffic controllers will work with police to find the sources of the lasers to enable timely law enforcement response.
Transportation Secretary Norman Mineta reported on January 12 that U.S. government agencies have found "no specific or credible intelligence that would indicate that these laser incidents are connected to terrorists." Additional intelligence community sources have confirmed to ALPA that the current spate of laser incidents cannot be linked to terrorism.
Based on these facts, the incidents seem to be the work of individual lawbreakers, rather than terrorists-or, in the words of Secretary Mineta, "careless people making stupid choices to put pilots and their passengers at risk." ALPA recommends that law enforcement agencies take this concern very seriously and fully investigate and bring to justice those who intentionally illuminate cockpits with lasers, regardless of their motivations.
ALPA's president, Capt. Duane Woerth, praised Secretary Mineta's actions in establishing the new reporting procedures.
"ALPA has been calling for improved information flow, both for reporting incidents or suspicious activity of any kind to a central office for analysis and for disseminating security information to pilots," Capt. Woerth said. "The new procedures for reporting laser incidents and broadcasting this information to pilots in the cockpit are an important first step toward that goal."
Capt. Woerth added, "Although the U.S. government knows of no specific, credible evidence that terrorists may be involved in these laser incidents, we must not assume that this is the reality. We urge the Department of Homeland Security and other appropriate agencies to continue monitoring for any indications of terrorist connections to such activity."
Technologies have been developed to mitigate the effects of lasers, but to date, airlines have not installed them in their cockpits.
one ALPA pilot safety representative also is an officer in the U.S. Air Force Reserves and is a member of the USAF Eye Protection Task Force (EPTF). As this issue of Air Line Pilot was going to press, the EPTF was scheduled to give, to manufacturers of optical devices for the Department of Defense, the specifications for goggles designed to protect flightcrew members from laser illumination of their cockpits. The goggles would have to permit pilots to see cockpit instruments and lights, including head-up displays, plus the world outside the cockpit, without significantly affecting their vision.
The EPTF has actively sought out members of the U.S. civil aviation community to share the results of its work to date. According to the EPTF, if airlines took advantage of the Air Force's lead, protective goggles costing $300-$500 apiece could be installed in airline cockpits within a year.
Meanwhile, manufacturers of laser pointers report that recent publicity about laser illumination of cockpits has led to a surge in sales. Only time will tell whether this latest proliferation of over-the-counter lasers will be accompanied by an increased public awareness of the dangers of--and the penalties for--pointing them at aircraft.
When the optical laser was invented in 1960, some people said it was "just a solution looking for a problem." Even the most visionary could scarcely imagine the proliferation of lasers in the last four decades--not just in research labs, but in surgery, manufacturing, and military weaponry, and in many objects now seen as commonplace, such as carpentry levels, CD players, aircraft "gyros," sportsmen's rangefinders, and much more.
In the United States, the Food and Drug Administration regulates commercially available lasers, such as laser pointers common in lecture halls and popular with amateur astronomers for pointing out celestial objects. The FDA restricts such consumer devices to 5 milliwatts of power output. A 4-watt nightlight bulb that barely shows you the path to the bathroom puts out 800 times that much energy.
So why are lasers so much more dangerous to the human eye than regular light?
Regular light contains visible electromagnetic radiation of many wavelengths, each appearing to us as a particular color. Mixed together, they appear to us as white light. Moreover, regular light waves spread out as they radiate from their source. Thus the intensity of the energy they convey decreases rapidly with distance.
Lasers, however, manipulate light or other wavelengths of electromagnetic energy in some remarkable ways. A visible laser creates, amplifies, and transmits a narrow, concentrated beam of light. Laser is an acronym for light amplification by stimulated emission of radiation.
Laser light is all of the same wavelength, with all of the waves in phase with each other, like horizontal stripes in a wind-rippled flag. Because the waves are parallel, laser light stays in a tight, coherent beam for long distances--again, like the stripes in a very long flag. Under ideal atmospheric conditions, a 5-milliwatt laser pointer can project a beam as far as 5 miles.
A laser beam is always a single color because the waves of light are the same length. The retina in the human eye is 36 to 50 times more sensitive to green light than to red (the number depending on which research you read). Thus the green laser pointers that are now supplanting their red predecessors are that much more dangerous to human sight.
"A common misconception," says an ALPA pilot safety representative, "is that you have to be looking directly at the laser for the light to affect your vision. You don't-depending on the strength of the laser, your distance from it, atmospheric conditions, and other factors, the laser light reflecting from objects in the cockpit can still be a hazard to safety of flight."
Lasers in the Spotlight
ALPA's National officers, National Security Committee, and Communications Department responded to calls from journalists and generated strategic opportunities to present line pilots' perspectives on lasers in prominent national news media outlets. ALPA's spokespersons have appeared in outlets including CNN, ABC World News Tonight, USA Today, the Associated Press, The Washington Times, The Christian Science Monitor, and The Boston Globe.
Here's ALPA's public message on lasers:
--Linda Shotwell, Senior Communications Specialist