14-1 CHAPTER 14. AIRCRAFT DETECTION LIGHTING SYSTEMS
14.1 Purpose.
Aircraft Detection Lighting Systems (ADLS) are sensor-based systems designed to detect aircraft as they approach an obstruction or group of obstructions; these systems automatically activate the appropriate obstruction lights until they are no longer needed by the aircraft. This technology reduces the impact of nighttime lighting on nearby communities and migratory birds and extends the life expectancy of obstruction lights.
14.2 General Standards.
14.2.1 The system should be designed with sufficient sensors to provide complete detection coverage for aircraft that enter a three-dimensional volume of airspace, or coverage area, around the obstruction(s) (see Figure A-27 in Appendix A), as follows:
1. Horizontal detection coverage should provide for obstruction lighting to be activated and illuminated prior to aircraft penetrating the perimeter of the volume, which is a minimum of 3 NM (5.5 km) away from the obstruction or the perimeter of a group of obstructions.
2. Vertical detection coverage should provide for obstruction lighting to be activated and illuminated prior to aircraft penetrating the volume, which extends from the ground up to 1,000 feet (304 m) above the highest part of the obstruction or group of obstructions, for all areas within the 3 NM (5.5 km) perimeter defined in subparagraph 14.2.1 1 above.
3. In some circumstances, it may not be possible to meet the volume area defined above because the terrain may mask the detection signal from acquiring an aircraft target within the 3 NM (5.5 km) perimeter. In these cases, the sponsor should identify these areas in their application to the FAA for further evaluation.
4. In some situations, lighting not controlled by the ADLS may be required when the 3 NM (5.5 km) perimeter is not achievable to ensure pilots have sufficient warning before approaching the obstructions.
14.2.2 The ADLS should activate the obstruction lighting system in sufficient time to allow the lights to illuminate and synchronize to flash simultaneously prior to an aircraft penetrating the volume defined above. The lights should remain on for a specific time period, as follows:
1. For ADLSs capable of continuously monitoring aircraft while they are within the 3 NM/1,000 foot (5.5 km/304 m) volume, the obstruction lights should stay on until the aircraft exits the volume. In the event detection of the aircraft is lost while being continuously monitored within the 3 NM/1,000 foot (5.5 km/304 m) volume, the ADLS should initiate a 30-minute timer and keep the obstruction lights on until the timer expires. This should provide the untracked aircraft sufficient time to exit the area and give the ADLS time to reset.
14-2
2. For ADLSs without the capability of monitoring aircraft targets in the 3 nm/1,000 foot (5.5 km/304 m) volume, the obstruction lights should stay on for a preset amount of time, calculated as follows:
a. For single obstructions: 7 minutes.
b. For groups of obstructions: (the widest dimension in nautical miles + 6) x 90 seconds equals the number of seconds the light(s) should remain on.
14.2.3 Acceptance of ADLS applications will be on a case-by-case basis and may be modified, adjusted, or denied based on proximity of the obstruction or group of obstructions to airports, low-altitude flight routes, military training areas, or other areas of frequent flight activity. It may be appropriate to keep certain obstructions closest to these known activity areas illuminated during the nighttime hours, while the remainder of the group’s obstruction lighting is controlled by the ADLS.
14.2.4 Project sponsors requesting ADLS use should include in their application maps or diagrams indicating the location of the proposed sensors, the range of each sensor, and a visual indication showing how each sensor’s detection arc provides the full horizontal and vertical coverage, as required under paragraph 14.2.1. In the event that detection coverage is not 100 percent due to terrain masking, project sponsors should provide multiple maps or diagrams that indicate coverage at the affected altitudes. A sample diagram is shown in Figure A-27 in Appendix A.
14.2.5 Types of ADLS Component or System Failure Events.
1. In the event of an ADLS component or system failure, the ADLS should automatically turn on all the obstruction lighting and operate in accordance with this AC as if it was not controlled by an ADLS. The obstruction lighting must remain in this state until the ADLS and its components are restored.
2. In the event that an ADLS component failure occurs and an individual obstruction light cannot be controlled by the ADLS, but the rest of the ADLS is functional, that particular obstruction light should automatically turn on and operate in accordance with this AC as if it was not controlled by an ADLS, and the remaining obstruction lights can continue to be controlled by the ADLS. The obstruction lighting will remain in this state until the ADLS and its components are restored.
3. Complete light failure should be addressed in accordance with Chapter 2 paragraph 2.4.
14.2.6 The ADLS’s communication and operational status shall be checked at least once every 24 hours to ensure both are operational.
14.2.7 The ADLS should be able to detect an aircraft with a cross-sectional area of 1 square meter or more within the volume, as required in subparagraphs 14.2.1 1 and 14.2.1 2.
14.2.8 Each ADLS installation should maintain a log of activity data for a period of no less than the previous 15 days. This data should include, but not be limited to, the date, time, duration of all system activations/deactivations, track of aircraft activity,
14-3 maintenance issues, system errors, communication and operational issues, lighting outages/issues, etc.
14.2.9 Operational Frequencies.
1. Unlicensed devices (including FCC Part 15) devices cannot be used for this type of system.
2. Any frequency used for the operation of ADLS must be individually licensed through the FCC.
14.3 Voice/Audio Option.
14.3.1 ADLS may include an optional voice/audio feature that transmits a low-power, audible warning message to provide pilots additional information on the obstruction they are approaching.
14.3.2 The audible transmission should be in accordance with appropriate FAA and FCC regulations.
14.3.3 The audible transmission should be over an aviation frequency licensed by the FCC and authorized under the Code of Federal Regulations Title 47- Part 87.483 (excluding
121.5 MHz).
Note: Using air traffic control frequencies in the 117.975-MHz to 137-MHz frequency band is prohibited for this operation.
14.3.4 The audible message should consist of three quick tones, followed by a verbal message that describes the type of obstruction the system is protecting. Appropriate terms to be used include tower(s), wind turbine(s), or power line(s).
14.3.5 The audible message should be repeated three times or until the system determines the aircraft is no longer within the audible warning area defined in the following paragraph.
14.3.6 The audible message should be considered as a secondary, final warning and should be activated when an aircraft is within 1/2 NM (926 m) horizontally and 500 feet (152 m) vertically of the obstruction. The use of, or variation to, the audible warning zone may occur, depending on site-specific conditions or obstruction types.
Appendix A A-1 APPENDIX A. SPECIFICATIONS FOR OBSTRUCTION LIGHTING EQUIPMENT
CLASSIFICATION Table A-1. FAA-Approved Obstruction Lighting Fixtures Type Symbol Description L-810
Steady-Burning - RED Single Obstruction Light L-810
Steady-Burning – RED Double Obstruction Light L-856
High-Intensity Flashing – WHITE Obstruction Light (40 FPM) L-857
High-Intensity Flashing – WHITE Catenary Light (60 FPM) L-864
Medium-Intensity Flashing – RED Obstruction Light (20-40 FPM) L-865
Medium-Intensity Flashing – WHITE Obstruction Light (40-FPM) L-866
Medium-Intensity Flashing - WHITE Catenary Light (60-FPM) L-864/L-865
Medium-Intensity Flashing Dual – RED / WHITE Obstruction Light (20-40 FPM) Obstruction Light (40 FPM) L-885
Low-Intensity Flashing - RED Red Catenary Light (60 FPM) FPM = Flashes Per Minute
Appendix A
CATENARY UNLIGHTED MARKERS Required for transmission lines less than 69 kV Recognizable from a minimum distance of 4,000 ft (1,219 m) Wire markers may be staggered over the catenary to enable better wind load distribution 200 ft (61 m)
- Violation Area (Above 200 ft (61 m) AGL) 25 ft (8 m) max distance unless line design sag requirements are greater Unlighted Marker Ball Extensive catenary wires: min 36-inch- (91-cm-) diameter markers; less extensive catenary wires: 20-inch- (51-cm-) or 12-inch-
(30.48-cm-) diameter markers.
Evenly spaced along the wire at approximately 200-ft (61-m) intervals.
Lighted markers should be a solid color, such as aviation orange, white or yellow.
Lighted markers should alternate aviation orange, white, yellow with aviation orange markers positioned at each end.
If less than four lighted markers are on the line, all markers should be aviation orange.
Figure A-1. Catenary Unlighted Markers A-2
Appendix A
CATENARY MARKERS - LINE SPACING Adjacent Lines Greater Than 200 ft (61 m) Away Required for transmission lines 69 kV or greater Recognizable from a minimum distance of 4,000 ft (1,219 m) Wire markers may be staggered over the catenary to enable better wind load distribution Greater Than 200 ft (61 m) 200 ft (61 m) Violation Area (Above 200 ft (61 m) AGL) 25 ft (8 m) max distance unless line design sag requirements are greater Unlighted Marker Ball Extensive catenary wires: min 36-inch- (91-cm-) diameter markers; less extensive catenary wires: 20-inch- (51-cm-) or 12-inch-
(30.48-cm-) diameter markers.
Evenly spaced along the wire at approximately 200-ft (61-m) intervals.
Unlighted markers should alternate aviation orange, white, yellow, with aviation orange markers positioned at each end.
If less than four markers (lighted or unlighted) are on the line, all markers should be aviation orange.
Catenary crossings with multiple transmission lines require additional line markers when the outside lines on the adjacent structure are more than 200-ft (61-m) from the center of the primary structure.
Figure A-2. Catenary Markers - Line Spacing (Adjacent Lines Greater Than 200 ft (61 m) Away) A-3
Appendix A
CATENARY MARKERS - LINE SPACING Adjacent Lines Within 200 ft (61 m) or Less Required for transmission lines less than 69 kV Recognizable from a minimum distance of 4,000 ft (1,219 m) Wire markers may be staggered over the catenary to enable better wind load distribution 200 ft (61 m) or Less 200 ft (61 m)
- Violation Area (Above 200 ft (61 m) AGL) 25 ft (8 m) max distance unless line design sag requirements are greater Unlighted Marker Ball Extensive catenary wires: min 36-inch- (91-cm-) diameter markers; less extensive catenary wires: 20-inch- (51-cm-) or 12-inch-
(30.48-cm-) diameter markers.
Evenly spaced along the wire at approximately 200-ft (61-m) intervals.
Unlighted markers should alternate aviation orange, white, yellow, with aviation orange markers positioned at each end.
If less than four markers (lighted or unlighted) are on the line, all markers should be aviation orange.
Catenary crossings with multiple transmission lines require additional line markers when the outside lines on the adjacent structure are more than 200-ft (61-m) from the center of the primary structure.
Figure A-3. Catenary Markers - Line Spacing (Adjacent Lines Within 200 ft (61 m) or Less A-4
Appendix A
CATENARY OBSTRUCTION LIGHTING Day Protection = 270,000 cd White Light Twilight Protection = 20,000 cd White Light Night Protection = 2,000 cd Red Light Flash Sequence = Middle | Top | Bottom Top - Middle Bottom 20% Variance Allowed
TOP CATENARY TOWER 60 ЕРМ IN THE MIDDLE OF THE CROSSING Middle Bottom 55 ГРМ - 60 гРМ - 20% Variance Allowed = L-857 (Flashing White Light) = 360° Visibility (Catenary Light 60 FPM) - (3) Flashheads per level for 360° coverage) = L-866 (Flashing White Light) = 180° Visibility (RIGHT) (Catenary Light 60 FPM) = L-885 (Flashing Red Light) = 180° Visibility (LEFT) (Catenary Light 60 FPM) Figure A-4. Catenary Obstruction Lighting А-5
Appendix A
CATENARY LIGHTED MARKERS Used in Conjunction with Unlighted Markers Required for transmission lines 69 kV or greater Recognizable from a minimum distance of 4,000 ft (1,219 m) Wire markers may be staggered over the catenary to enable better wind load distribution 200 ft (61 m)
- Violation Area (Above 200 ft (61 m) AGL) 25 ft (8 m) max distance unless line design sag requirements are greater Unlighted Marker Ball Lighted Marker Ball Extensive catenary wires: min 36-inch- (91-cm-) diameter markers; less extensive catenary wires: 20-inch- (51-cm-) or 12-inch-
(30.48-cm-) diameter markers.
Evenly spaced along the wire at approximately 200-ft (61-m) intervals.
Lighted and unlighted markers should be a solid color, such as aviation orange, white or yellow.
Lighted and unlighted markers should alternate aviation orange, white, yellow with aviation orange markers positioned at each end.
If less than four markers (lighted or unlighted) are on the line, all markers should be aviation orange.
Figure A-5. Catenary Lighted Markers A-6
Appendix A
RED OBSTRUCTION LIGHT
STANDARDS (FAA STYLE A) Day Protection = Aviation Orange / White Paint Night Protection = 2,000 cd Red Light (32 cd Red Side lights for A1) 1,901 ft (579 m) - 2,100 ft (640 m) Paint Bands (Twenty-One) 1,701 ft (518 m) - 1,900 ft (579 m) Paint Bands (Nineteen) Above 1,750 ft - 2,200 ft (522 m - 671 m) 1,501 ft (547 m) - 1,700 ft (518 m) Paint Bands (Seventeen) Above 1,400 ft - 1,750 ft 1,301 ft (396 m) - 1,500 ft (547 m) Paint Bands (Fifteen) (427 m - 533 m) 1,101 ft (335 m) - 1,300 ft (396 m) Paint Bands (Thirteen) Above 1,050 ft - 1,400 ft (320 m - 427 m) 901 ft (274 m) - 1,100 ft (335 m) Paint Bands (Eleven) 701 ft (213 m) - 900 ft (274 m) Above 700 ft - 1,050 ft Paint Bands (Nine) (213 m - 320 m)
10.5 ft (3 m) - 700 ft (213 m) Paint Bands (Seven) Above 350 ft - 700 ft (107 m - 213 m) Two or more L-810 lights configured to flash in sync with L-864 Above 150 ft - 350 ft (46 m - 107 m) 0 ft - 150 ft (0 m - 46 m) VIN AO A1 A2 A3 A4 A5 A6 PAINT BANDS = 1-864 (Flashing Red Light) Configured to flash at a rate of 30 fpm (+ 3 fpm) = L-810 (Single Light) Configured to flash in sync with L-864 = L-810 (Double Light) Figure A-6. Red Obstruction Light Standards A-7
Appendix A
MEDIUM-INTENSITY WHITE OBSTRUCTION LIGHT
STANDARDS (FAA STYLE D) Day / Twilight Protection = 20,000 cd White Light Night Protection = 2,000 cd White Light (Painting of tower is typically not required) One-half but not lower than 200 it (61 m) Above 350 ft - 700 ft (107 m - 213 m) Above 200 ft - 350 ft (61 m - 107 m) D1 D2 = L-865 (Flashing White Light) Figure A-7. Medium-Intensity White Obstruction Light Standards A-8
Appendix A
HIGH-INTENSITY WHITE OBSTRUCTION LIGHT
STANDARDS (FAA STYLE B) STRUCTURE WITH APPURTENANCE 40 ft (12 m) OR LESS Day Protection = 270,000 cd White Light Twilight Protection = 20,000 cd White Light Night Protection = 2,000 cd White Light
• e Above 1,750 ft - 2,200 ft (533 m - 671 m) Appurtenance Above 1,400 ft - 1,750 ft 40 ft (12 m) or less (427 m - 533 m) Above 1,050 ft - 1,400 ft (320 m - 427 m) Above 700 ft - 1,050 ft (213 m - 320 m) For towers 700 ft (213 m) and below, see the appropriate medium-intensity FAA style sheet ВЗ B4 B5 B6 = L-856 (Flashing White Light) (3 flash heads required per level for 360° coverage) Figure A-8. High-Intensity White Obstruction Light Standards-Structures With Appurtenance 40 Feet or Less A-9