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Patrick Murphy Executive Director, International Laser Display Association SAE G-10T Committee Member. Lasers and aviation Safety. Lasers and Aviation Safety. Laser pointer threat Laser uses in airspace Laser hazards in airspace Hazard factors Hazard reduction Regulation and control.
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Patrick Murphy Executive Director, International Laser Display Association SAE G-10T Committee Member Lasers and aviation Safety
Lasers and Aviation Safety • Laser pointer threat • Laser uses in airspace • Laser hazards in airspace • Hazard factors • Hazard reduction • Regulation and control
Laser pointer threat • Steady rise in incidents • Due to: • Lower cost • Higher powers(100-300 mW) • Green (more visible)
Laser pointer threat • January 1 – February 23, 2009: 148 laser illuminations of aircraft in the U.S. alone • 2.7 per day • February 22: 12 illuminations of aircraft landing at Sea-Tac
Laser pointer threat -- Australia • 140 incidents Jan. - April 2008 • March 2008 “coordinated attacks” in Sydney • Led to NSW ban on laser pointer import, sales and possession
Laser use in airspace • “Guide star” lasers used in astronomy • Satellite communications and ranging • Atmospheric remote sensing
Laser use in airspace • Aircraft warning • Visual Warning System used in Washington Metropolitan Air Defense Identification Zone (ADIZ) • 7 locations • Green and red lasers, 1.5 watts • Visible up to 20 nautical miles away
Laser use in airspace • Entertainment • Nightly show at a fixed site (theme parks) • Infrequent shows at various sites (special events) • Usually only 30-60 minutes long
Not practical to ban lasers from airspace • Unduly restricts legitimate users • Does not prevent accidental illumination incidents • Does not stop deliberate targeting of aircraft • Ignorance – does not know effects • Malice – trying to cause harm
Primary hazard is to pilots • From visible laser beams: • Visual interference during critical phases of flight • Distraction, glare and flashblindness • Potential eye damage during any phase of flight • From non-visible (infrared, ultraviolet) beams: • Potential eye damage during any phase of flight
Visual interference • Distraction • Distracting, but can see past the light • 0.5 μW/cm2 • 5 mW laser pointer at 3,700 feet (1130m)
Visual interference • Glare • Interferes with vision • 5.0 μW/cm2 • 5 mW laser pointer at 1,200 feet (365m)
Visual interference • Temporary flashblindness • Blocks vision during and after exposure • 100 μW/cm2 • 5 mW laser pointer at 350 feet (107m)
Visual interference does affect pilots • 2004 FAA simulator study • Pilots flew a challenging “short-final” approach • Glare and flashblindness significant • Adverse effects for more than 50% of the approaches • 20-25% rate of aborted landings
Potential eye damage • Can be caused by visible or non-visible laser beams, at power above the MPE • Unlikely, though possible • Few confirmed reports • “Damage” could be pre- or post-exposure • Previous eye injuries or abormalities • Rubbing the eye after exposure
6 watt, 532 nm, 1.1 mrad laser • Eye hazard to 1600 feet (488m) • Flashblindness to 8200 feet (1.5 mi/2.5 km) • Glare to 36,800 feet (7 mi/11.2 km) • Distraction to 368,000 feet (70 mi/112 km)
Factors affecting hazard level • Laser factors • Power, divergence, visible/non-visible, wavelength, pulsed vs. CW • Operational factors • Area covered in sky (stationary vs. moving) • Location relative to airports • Terminated vs. non-terminated beams • Use of airspace observers (spotters) • Use of automated detection (radar, cameras)
Factors affecting hazard level (cont. 1) • Situational factors • Day vs. night • Aircraft speed and distance (helicopters at risk) • Laser pointer user factors • Deliberate (longer and more exposures) vs. accidental (short, single event)
Factors affecting hazard level (cont. 2) • Pilot factors • Read NOTAMs • Flight phase (takeoff, landing, emergency) • Pilot experience and training • Recognizing a laser event • Properly responding, to successfully avoid problems
Factors affecting hazard level (cont. 3) • Legal and regulatory • Follow aviation authority procedures • FAA, CDRH in US • Laws against interference • Restrict the sale or use of laser devices • May not be practical • May give false sense of security • Does not guard against deliberate intent
Pilot training reduces the hazard • Laser illuminations can be managed with training • Effective against both accidental and deliberate exposures • Not a substitute for regulations and restrictions on law-abiding laser users
Public education may also help • Educate heavy laser pointer users • www.LaserPointerSafety.com • Self-regulation/education by laser pointer sellers • Package inserts • Permanent labels on laser pointers • Laser pointer seller participation in regulatory efforts • Laser pointer seller trade association
www.LaserPointerSafety.com • Facts, news and links on laser pointer safety for the general public • Reduce annoying and dangerous incidents • “Bad for safety” – pilots, drivers • “Bad for yourself” – possible arrest, fines, jail • “Bad for pointers” – misuse will lead to bans
U.S. regulations • Federal Aviation Administration • Does not have direct authority over laser uses • Requests that laser uses be reviewed in advance by aerospace specialists • Issues a “Letter of Non-Objection” if OK;a “Letter of Objection” if not OK
U.S. regulations • FDA’s Center for Devices and Radiological Health • Regulates laser devices (equipment) • Only regulates three uses • Medical • Surveying • Demonstration • Includes laser pointers and light shows • Demonstration users MUST file with FAA and MUST get a “Letter of Non-Objection”. Only laser users legally required to get permission.
FAA regulations • Four zones around airports and sensitive airspace, for visual interference • “Laser-Free” Zone, < 0.5 μ/cm2 (50 nanowatts/cm2) • Critical Flight Zone, < 5.0 μ/cm2 • (optional) Sensitive Flight Zone, < 100 μ/cm2 • Normal Zone, <MPE, no visual restrictions
What U.S. airspace is controlled? • Almost all lasers outdoors in the U.S. • Even if between two buildings on a city street • Helicopters may need to fly between the buildings • Even if terminated from ground to surfaces • Termination may fail • FAA control stops at about 60,000 feet • Some lasers are hazards above 60,000 feet • Must be reported to Air Force Space Command • No current requirement to detect hard-to-spot aircraft • Stealth, unmanned aerial vehicles, supersonic
How to report U.S. laser operations • FAA Form 7140-1 (part of Advisory Circular 70-1)
Standards development • SAE G-10T Laser Safety Hazards Subcommittee • ANSI Z136.6 Standard for Safe Use of Lasers Outdoors
Current status • SAE G-10T working on guidelines for automated detection and avoidance systems • Prominent laser users (e.g., observatories) and laser shows follow FAA guidelines • Laser pointers now are the area of primary concern • Some concern over deliberate targeting to cause harm • Difficult to do, not very effective
Resources for background, general public • This ILSC paper and its references • Wikipedia article “Lasers and Aviation Safety” • Subject to “anyone can edit” caveat of any Wikipedia article • www.LaserPointerSafety.com • Links page