AC 70/7460-1M 11/16/2020
4.2 Standards14
4.3 Lighting Systems14
4.4 Inspection, Repair, and Maintenance15
4.5 Nonstandard Lights16
4.6 Placement Factors16
4.7 Monitoring Obstruction Lights17
4.8 Ice Shields18
4.9 Light Shields18
4.10 Distractions18
CHAPTER 5. RED OBSTRUCTION LIGHT SYSTEM19
5.1 Purpose19
5.2 Standards19
5.3 Control Device20
5.4 Alternate Method of Displaying Obstruction Lights20
5.5 Poles, Towers, and Similar Skeletal Structures20
5.6 Chimneys, Flare Stacks, and Similar Solid Structures (except Hyperbolic
Cooling Towers)21
5.7 Prominent Buildings, Bridges, and Similar Extensive Obstructions22
5.8 Group of Obstructions23
CHAPTER 6. MEDIUM-INTENSITY FLASHING WHITE OBSTRUCTION LIGHT
SYSTEMS25
6.1 Purpose25
6.2 Standards25
6.3 Control Device25
6.4 Radio and Television Towers and Similar Skeletal Structures25
6.5 Chimneys, Flare Stacks, and Similar Solid Structures27
6.6 Prominent Buildings and Similar Extensive Obstructions27
6.7 Group of Obstructions28
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6.8 Special Cases28
CHAPTER 7. HIGH-INTENSITY FLASHING WHITE OBSTRUCTION LIGHT
SYSTEMS29
7.1 Purpose29
7.2 Standards29
7.3 Control Device29
7.4 Units per Level29
7.5 Installation Guidance30
7.6 Radio and Television Towers and Similar Skeletal Structures31
7.7 Antenna or Similar Appurtenance Light32
7.8 Chimneys, Flare Stacks, and Similar Solid Structures32
7.9 Prominent Buildings and Similar Extensive Obstructions32
7.10 Hyperbolic Cooling Towers33
7.11 Special Cases33
CHAPTER 8. DUAL LIGHTING WITH RED/MEDIUM-INTENSITY FLASHING
WHITE LIGHT SYSTEMS34
8.1 Purpose34
8.2 Installation34
8.3 Operation34
8.4 Control Device34
8.5 Antenna or Similar Appurtenance Light34
8.6 Omission of Marking35
CHAPTER 9. DUAL LIGHTING WITH RED/HIGH-INTENSITY FLASHING WHITE
LIGHT SYSTEMS36
9.1 Purpose36
9.2 Installation36
9.3 Operation36
9.4 Control Device36
9.5 Antenna or Similar Appurtenance Light36
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9.6 Omission of Marking37
CHAPTER 10. AIRCRAFT DETECTION LIGHTING SYSTEMS38
10.1 Purpose38
10.2 General Standards38
CHAPTER 11. MARKING AND LIGHTING OF CATENARY AND CATENARY
SUPPORT STRUCTURES41
11.1 Purpose41
11.2 Lighted Spherical Markers41
11.3 Catenary Marking Standards41
11.4 Catenary Lighting Standards45
11.5 Control Device46
11.6 Area Surrounding Catenary Wire Support Structures47
11.7 Three or More Catenary Wire Support Structures47
CHAPTER 12. MARKING AND LIGHTING MOORED BALLOONS AND KITES48
12.1 Purpose48
12.2 Standards48
12.3 Marking48
12.4 Purpose48
12.5 Operational Characteristics49
CHAPTER 13. MARKING AND LIGHTING WIND TURBINES50
13.1 Purpose50
13.2 General Standards50
13.3 Wind Turbine Configurations50
13.4 Marking Standards51
13.5 Lighting Standards51
13.6 Wind Turbines Above 499 Feet (152.10 m)53
13.7 Wind Turbines at or Above 699 Feet (213.36 m)53
13.8 Lighting of Wind Turbines During Construction Phase54
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13.9 Lighting and Marking of Airborne Wind Turbines54
13.10 Lighting and Marking of Offshore Wind Turbines54
CHAPTER 14. MARKING AND LIGHTING TEMPORARY STRUCTURES55
14.1 Purpose55
14.2 General Standards55
14.3 Marking Standards55
14.4 Lighting Standards56
14.5 Operational Characteristics58
CHAPTER 15. MARKING AND LIGHTING EQUIPMENT AND INFORMATION59
15.1 Purpose59
15.2 Paint Standard59
15.3 Availability of Specifications and Advisory Circulars60
15.4 Lights and Associated Equipment Standards60
15.5 Availability of Military Specifications61
APPENDIX A: SPECIFICATIONS FOR OBSTRUCTION LIGHTING EQUIPMENT
CLASSIFICATION62
Table A-1. FAA-Approved Obstruction Lighting Fixtures63
Figure A-1. Meteorological Evaluation Tower (MET) Marking Standards
(Monopole Structure)64
Figure A-2. Meteorological Evaluation Tower (MET) Marking Standards (Guyed Structure)65
Figure A-3. Painting and Lighting of Water Towers, Storage Tanks, and Similar Structures66
Figure A-4. Painting and Lighting of Water Towers and Similar Structures67
Figure A-5. Painting a Single Pedestal Water Tower Using the Teardrop Pattern68
Figure A-6. Red Obstruction Light Standards (FAA Style A)69
Figure A-7. Dual Lighting of Poles, Towers, and Similar Structures/Lighting and
Painting of Chimneys70
Figure A-8. Bridge Lighting71
Figure A-9. Medium-Intensity White Obstruction Light Standards (FAA Style D)72
Figure A-10. Lighting of Chimneys, Flare Stacks, or Similar Solid Structures73
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Figure A-11. Lighting Adjacent Structures—Light Level Adjustment74
Figure A-12. Lighting Adjacent Structures75
Figure A-13. High-Intensity White Obstruction Light Standards (FAA Style B)—With
Appurtenance 40 Feet or Less76
Figure A-14. High-Intensity White Obstruction Light Standards (FAA Style C)—With
Appurtenance Over 40 Feet High77
Figure A-15. Lighting Hyperbolic Cooling Tower78
Figure A-16. Medium-Intensity Dual Obstruction Light Standards (FAA Style E)79
Figure A-17. Medium-Intensity Lighting—Establishing the Location of Top Beacons80
Figure A-18. High-Intensity Dual Obstruction Light Standards (FAA Style F)—With
Appurtenance Over 40 Feet High81
Figure A-19. High-Intensity Dual Obstruction Light Standards (FAA Style G)—With
Appurtenance 40 Feet or Less82
Figure A-20. Aircraft Detection Lighting System (sample coverage map)83
Figure A-21. Catenary Unlighted Markers (less than 69 kV)84
Figure A-22. Catenary Markers – Line Spacing (Adjacent Lines Within 200 ft.
(60.96 m) or Less)85
Figure A-23. Catenary Markers - Line Spacing (Adjacent Lines Greater Than 200 ft.
(60.96 m) Away)86
Figure A-24. Catenary Lighted Markers – Used in Conjunction with Unlighted Markers
(69 kV or greater)87
Figure A-25. Catenary Obstruction Lighting88
Figure A-26. Wind Turbine Lighting Configurations89
Figure A-27. Lighting and Marking of Wind Turbines – Paint Schemes90
Figure A-28. Wind Turbine Lighting and Marking in Snow Prone Areas (Optional)91
Figure A-29. Wind Turbine Lighting92
Figure A-30. Marking and Lighting of Turbines During Construction93
Figure A-31. Crawler Crane Marking and Lighting94
Figure A-32. Tower Crane Marking and Lighting95
Figure A-33. Container Crane Marking and Lighting96
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APPENDIX B: MISCELLANEOUS97
APPENDIX C: ACRONYMS99
CHAPTER 1. ADMINISTRATIVE AND GENERAL PROCEDURES
1.1 Reporting Requirements.
A Sponsor proposing any type of construction or alteration of a structure that may affect the National Airspace System (NAS) as required under the provisions of Code of Federal Regulations (CFR), Title 14, Aeronautics and Space, Part 77, Safe, Efficient Use, and Preservation of the Navigable Airspace (14 CFR, Part 77), is to notify the Federal Aviation Administration (FAA) by completing the FAA Form 7460-1, Notice of Proposed Construction or Alteration.
This form should be filed electronically at https://oeaaa.faa.gov. The website includes the FAA Notice Criteria Tool for Sponsors use to determine if the structure exceeds criteria threshold and requires a notice to be filed.
1.2 Preconstruction Notice.
The notice must be submitted:
1. At least 45 days prior to the date of proposed construction or alteration is to begin.
2. On or before the date an application for a construction permit is filed with the Federal Communications Commission (FCC). The FCC advises its applicants to file with the FAA well in advance of the 45-day period to expedite FCC processing.
1.3 FAA Acknowledgement.
The FAA will acknowledge, electronically, each FAA Form 7460-1 notice received.
1.4 Supplemental Notice Requirement.
1. If required, the FAA will include a statement requiring the filing of FAA Form 7460-2, Notice of Actual Construction or Alteration, on the determination. All FAA Forms 7460- 2 should be filed electronically at https://oeaaa.faa.gov.
2. FAA Form 7460-2, Part 1, must be submitted to the FAA at least ten days prior to starting the actual construction or alteration of a structure. The FAA Form 7460-2, Part 2, completed within five days after the structure has reached its greatest height.
3. In addition, notification of dismantlement or abandonment of construction must be submitted to the FAA using the supplemental notice FAA Form 7460-2.
Note: Notification as required in the determination is critical to aviation safety.
1.5 Modifications and Deviations.
Requests for modification or deviation from the standards outlined in this AC must be submitted to the FAA Obstruction Evaluation Group (OEG). The Sponsor is responsible for adhering to approved marking and/or lighting limitations, and recommendations given, and should notify the FAA and FCC (for those structures regulated by the FCC) prior to making any changes, such as removal of marking and/or lighting. Requests received for any changes after a determination has been issued will require a new aeronautical study and may result in a modified determination, including updated marking and/or lighting recommendations.
1. Modification examples. Modifications will be based on whether they impact aviation safety.
Examples of modifications are as follows:
a. Marking and/or lighting only a portion of an object. The object may be located with respect to other objects or terrain that only a portion of it needs to be marked and/or lighted.
b. No marking and/or lighting. The object may be located with respect to other objects or terrain, removed from the general flow of air traffic, or may be so conspicuous by its shape, size, or color that marking or lighting would serve no useful purpose.
c. Voluntary marking and/or lighting. The object may be located with respect to other objects or terrain that the Sponsor feels increased conspicuity would better serve aviation safety.
Sponsors who desire to voluntarily mark and/or light their structure should do so in accordance with this AC.
d. Marking or lighting an object in accordance with the standards for an object of greater height or size. The object may present such an extraordinary hazard potential that higher standards may be recommended for increased conspicuity to ensure aviation safety.
2. Deviations. The assigned Obstruction Evaluation Specialist will conduct an aeronautical study of the proposed deviation(s) and forward their recommendation to their FAA Team Manager for final approval. Examples of deviations that may be considered:
a. Colors of objects.
b. Dimensions of color bands or rectangles.
c. Colors/types of lights.
d. Basic signals and intensity of lighting.
e. Night/day lighting combinations.
f. Flash rate.
The FAA strongly recommends that owners become familiar with the different types of lighting systems and to specifically request the type of lighting system desired when submitting FAA Form 7460-1. Information regarding types of lighting systems is provided in Chapters 5 - 10, and specifications regarding lighting equipment classifications in Table A-1, in this AC. While the FAA will make every effort to accommodate the structure Sponsor’s request, Sponsors should also request information from system manufacturers to determine which system best meets their needs based on purpose, installation, and maintenance costs.
1.6 Additional Notification.
Proper authorization and annotations of obstruction marking and lighting may require notice to the FCC prior to making any change to the submitted information which the FAA based its determination. This includes modification, deviation, or optional upgrade to white lighting on structure, which may be subject to inspection and enforcement of marking and lighting requirements by the FCC. FCC Forms and Bulletins can be obtained from the FCC’s National Call Center at 1-888-CALL-FCC (1-888-225-5322) or online at: https://www.fcc.gov/wirelesstelecommunications. Additionally, upon completion of the actual change, complete the “Add Supplemental Notice (FAA Form 7460-2)” at the https://oeaaa.faa.gov website.
CHAPTER 2. GENERAL
2.1 Structures to be Marked and Lighted.
Any temporary or permanent structure, including all appurtenances, that exceeds any obstruction standard contained in 14 CFR Part 77 or an overall height of 200 feet (60.96m) above ground level (AGL) should be marked and/or lighted. However, an FAA aeronautical study may reveal that the absence of marking and/or lighting will not impair aviation safety. Conversely, the object may present such an extraordinary hazard potential that higher standards may be recommended for increased conspicuity to ensure aviation safety. Recommendations for marking and/or lighting structures can vary, depending on terrain features, weather patterns, geographic location, number of structures, and overall design layout. The FAA may also recommend marking and/or lighting a structure that does not exceed 200 feet (60.96 m) AGL or 14 CFR Part 77 standards because of its particular location. The marking and lighting configurations are illustrated in Appendix A.
2.2 Guyed Structures.
The guys of a 2,000-foot (609.60 m) skeletal tower are anchored between 1,600 feet (487.68 m) and 2,000 feet (609.60 m) from the base of the structure. This places a portion of the guys 1,500 feet (457.20 m) from the tower at a height of between 125 feet (38.10 m) and 500 feet (152.40
m) AGL. Title 14 CFR Part 91, Section 119, requires pilots, when operating over other than congested areas, to remain at least 500 feet (152.40 m) from man-made structures. Therefore, the tower must be cleared by 2,000 feet (609.60 m) horizontally to avoid all guy wires. Properly maintained marking and lighting are important for increased conspicuity because the guys of a structure are difficult to see until the aircraft is dangerously close.
2.3 Marking and Lighting Equipment.
Considerable effort and research was expended to determine the minimum marking and lighting systems and quality of materials that will produce an acceptable level of aviation safety. The FAA will recommend only those marking and lighting systems that meet established technical standards and commercial outside lighting should not be used in lieu of FAA recommended marking and/or lighting. While additional lights may be desirable to identify an obstruction to air navigation, and may on occasion be recommended, the FAA will recommend minimum standards in the interest of safety, economy, and related concerns. Therefore, to provide an adequate level of safety, obstruction lighting systems should be installed, operated, and maintained in accordance with the recommended standards herein. Chapter 15 contains descriptions of FAA- approved obstruction marking and lighting equipment and information referred to in this AC.
2.4 Light Failure Notification.
Sponsors should consider that conspicuity is achieved only when all recommended lights are working. Partial equipment outages decrease the margin of safety. Any outage should be corrected as soon as possible. Failure of steady-burning side or intermediate lights should be corrected as soon as possible, but notification is not required.
Note: On September 11, 2020, the FAA changed specifications for LED-based red obstruction lights to make them visible to pilots using certain night vision goggle systems.
Effective with implementation of this change in FAA AC 150/5345-43, Specification for Obstruction Lighting Equipment, manufacturers will be required to meet the new specification for certified red LED-based obstruction lights.
Because the new specification ensures the light is visible to pilots operating with night vision goggles, there is risk of a pilot misinterpreting the tower height if a legacy intermediate-level light is replaced with one that meets the new specification unless the top light meets the new specification as well. Therefore, if a legacy specification intermediate-level LED-based light is replaced with a light that meets the new specifications, then the top-level light(s) on the obstruction must also meet the new specification to ensure the entire obstruction is visible during the use of night vision goggles.
2.4.1. Any failure or malfunction that lasts more than thirty (30) minutes and affects a top light, flashing obstruction light regardless of its position, wind turbine lighting fixture, or wind turbine synchronization should be reported immediately by calling Outage Reporting and Notice to Airmen (NOTAM) at 877-487-6867, or in Alaska 800-478- 3576, so a NOTAM can be issued.
For structures that are regulated by the FCC, the FCC advises that noncompliance with notification procedures could subject the Sponsor to penalties or monetary forfeitures.
Voluntarily installed lights (not required by an FAA determination) do not require a NOTAM.
2.4.2. The following information should be specified for outage reporting:
1. Name of persons or organizations reporting the light failures, including any title, address, and telephone number.
2. The type of structure.
3. Location of structure (including latitude and longitude, prominent structures, landmarks, etc.).
4. Height of structure AGL/above mean sea level (AMSL) if known.
5. Return to service date.
6. FCC Antenna Structure Registration Number (for structures that are regulated by the FCC).
Note: When the primary lamp in a double obstruction light fails and the secondary lamp comes on, no report is required.
2.5 Notification of Restoration.
As soon as normal operation is restored, notify Outage Reporting and NOTAM Offices (see Paragraph 2.4.1).
Note: For structures regulated by the FCC, the FCC advises that noncompliance with notification procedures could subject the Sponsor to penalties or monetary forfeitures.
2.6 Federal Communications Commission (FCC) Requirement.
The use of a high-intensity flashing white lighting system on structures located in residential neighborhoods (as defined by applicable zoning laws) trigger requirements for FCC licenses and an environmental assessment.
2.7 Voluntary Marking of Meteorological Evaluation Towers (MET) Less Than 200 Feet (60.96
m) AGL.
The FAA recommends voluntary marking of MET less than 200 feet (60.96 m) AGL in accordance with marking guidance contained in this AC. Historically this guidance has not been applied, however the FAA recognizes the need to address safety impacts to low-level agricultural flight operations and believes that voluntarily marking MET less than 200 feet (60.96 m) AGL in remote and rural areas enhance the conspicuity of these structures.
1. Painting. The MET should be painted in accordance with the standards and criteria contained in Chapters 3 and 15, with alternating bands of aviation orange and white paint. In addition, paragraph 3.3.1 states that all markings should be replaced when faded or otherwise deteriorated.
2. High-visibility sleeves. It is recommended that several high-visibility sleeves be installed on the MET outer guy wires (see Figure A-2). One high- visibility sleeve should be installed on each guy wire, as close to the anchor point as possible, but at a height well above the crop or vegetation canopy. A second sleeve should be installed on the same outer guy wires midway between the location of the lower sleeve and the upper attachment point of the guy wire to the MET.
Spherical markers. It is also recommended that high-visibility aviation orange spherical marker (or cable) balls be attached to the guy wires. Spherical markers should be installed and displayed in accordance to Chapter 11. The FAA, however, recognizes various weather conditions and manufacturing placement standards may affect the placement and use of high-visibility sleeves and/or spherical markers. Thus, some flexibility is allowed when determining sleeve length and marker placement on the MET.