The outdoor use of lasers and other high intensity light sources in relation to air traffic safety
report
High intensity light sources like searchlights (in the Netherlands sometimes referred to as skybeamers) are increasingly deployed in the open air at public events, funfairs, or to attract attention to commercial venues. Other high intensity light sources like (handheld) spotlights are frequently used near construction sites or sport events. As a result, the Inspectie Verkeer en Waterstaat (the Dutch Civil Aviation Authority, CAA NL) regularly receives applications for permission to use high intensity light sources in the open airspace. Since it is currently not known how high intensity light sources may affect air traffic safety, the CAA NL is not able to assess the risks involved in the deployment of high intensity lights in the navigable airspace or to appropriately regulate their use. The CAA NL therefore commissioned TNO to investigate the effects of high intensity light sources (other than lasers) on air traffic, and (if necessary) to propose regulations and/or safety measures. In addition, the CAA NL asked TNO to investigate the safety measures that have been implemented or that may be required to guarantee the safe use of high power scientific laser installations in the Netherlands.
We investigated the effects of several broadband high intensity light sources and a common 3.5 mW green laser pointer on pilot vision at night. We also investigated the safety measures that are deployed for two laser systems for atmospheric research in the Netherlands.
Accurate knowledge of the visual effects induced by high intensity lights is required to assess the risks for air traffic related to their deployment in the navigable airspace and to appropriately regulate their use. Similarly, the effectiveness of safety measures for scientific laser systems should be known in order to assess their risks for air traffic.
Since the visual and biological effects of high intensity lights are similar to those induced by lasers, existing laser safety zoning around airports can also be applied to regulate the use of other high intensity light sources.
On the ground we measured the luminance of several representative high intensity lights as a function of distance, and their beam width. From these measurements we calculated the distances at which their illuminance exceeded the critical levels associated with laser safety zones around airports. We also interviewed the operators of two operational scientific laser systems on their safety protocols.
We also performed helicopter flight tests to validate the computed visual interference distances. We found that in normal use, broadband high intensity light sources pointing in navigable airspace, whether stationary or moving, cause no concern for aviation safety outside the Laser Free Zone. Intentional tracking of an aircraft with a high intensity light source may cause serious glare and distraction. Distraction may also occur when the high intensity light is the only bright light source in its environment, even when the light is not directed at the plane.
The visual impact of the laser pointer was serious when its beam hit the canopy of the helicopter. The light was unacceptably bright and caused serious glare at a distance of about 500 m. At this distance it also elicited brief afterimages. The laser pointer could not be seen when its beam did not directly hit the eye.
Both scientific systems (at ESA-ESTEC, Noordwijk and at RIVM, Bilthoven) that are currently operational for atmospheric research have sufficient safety precautions (radar and human observers) and cause no appreciable risk for aviation safety.
We conclude that there is no need to restrict broadband high intensity light sources pointing in navigable airspace anywhere outside the Laser Free Zone. The use of high intensity light sources inside the Laser Free Zone should be avoided since they can cause distraction. Intentionally tracking aircraft with a high intensity light, and especially with lasers, can seriously impair pilot vision. The safety protocols of the scientific laser systems that are currently used in the Netherlands (radar and human observers) are sufficient to guarantee aviation safety for commercial aircraft.
We investigated the effects of several broadband high intensity light sources and a common 3.5 mW green laser pointer on pilot vision at night. We also investigated the safety measures that are deployed for two laser systems for atmospheric research in the Netherlands.
Accurate knowledge of the visual effects induced by high intensity lights is required to assess the risks for air traffic related to their deployment in the navigable airspace and to appropriately regulate their use. Similarly, the effectiveness of safety measures for scientific laser systems should be known in order to assess their risks for air traffic.
Since the visual and biological effects of high intensity lights are similar to those induced by lasers, existing laser safety zoning around airports can also be applied to regulate the use of other high intensity light sources.
On the ground we measured the luminance of several representative high intensity lights as a function of distance, and their beam width. From these measurements we calculated the distances at which their illuminance exceeded the critical levels associated with laser safety zones around airports. We also interviewed the operators of two operational scientific laser systems on their safety protocols.
We also performed helicopter flight tests to validate the computed visual interference distances. We found that in normal use, broadband high intensity light sources pointing in navigable airspace, whether stationary or moving, cause no concern for aviation safety outside the Laser Free Zone. Intentional tracking of an aircraft with a high intensity light source may cause serious glare and distraction. Distraction may also occur when the high intensity light is the only bright light source in its environment, even when the light is not directed at the plane.
The visual impact of the laser pointer was serious when its beam hit the canopy of the helicopter. The light was unacceptably bright and caused serious glare at a distance of about 500 m. At this distance it also elicited brief afterimages. The laser pointer could not be seen when its beam did not directly hit the eye.
Both scientific systems (at ESA-ESTEC, Noordwijk and at RIVM, Bilthoven) that are currently operational for atmospheric research have sufficient safety precautions (radar and human observers) and cause no appreciable risk for aviation safety.
We conclude that there is no need to restrict broadband high intensity light sources pointing in navigable airspace anywhere outside the Laser Free Zone. The use of high intensity light sources inside the Laser Free Zone should be avoided since they can cause distraction. Intentionally tracking aircraft with a high intensity light, and especially with lasers, can seriously impair pilot vision. The safety protocols of the scientific laser systems that are currently used in the Netherlands (radar and human observers) are sufficient to guarantee aviation safety for commercial aircraft.
TNO Identifier
93673
Publisher
TNO
Collation
54 p.
Place of publication
Soesterberg