AC 70/7460-1L

U.S. Department of Transportation Federal Aviation Administration Advisory Circular Subject: Obstruction Marking and Lighting Date: 12/04/15 Initiated By: AJV-15 AC No: 70/7460-IL

1. Purpose.

This Advisory Circular (AC) sets forth standards for marking and lighting obstructions that have been deemed to be a hazard to navigable airspace.

2. Advisory Circular 70/7460-1L is effective immediately. However, flashing L-810 lighting has a delayed effective date and becomes mandatory on September 15, 2016.

3. Cancellation.

Advisory Circular 70/7460-1K, Obstruction Lighting and Marking, dated February 1, 2007, is cancelled.

4. Principal Changes.

The principal changes in this AC are:

1. The height of a structure identified as an obstruction has been lowered from 500 feet above ground level (AGL) to 499 feet above ground level, by amendment to Title 14 Code of Federal Regulations (14 CFR) Part 77, Safe, Efficient Use, and Preservation of the Navigable Airspace (75 Federal Register 42303, July 21, 2010).

Accordingly, all structures that are above 499 feet AGL are considered obstructions and the Federal Aviation Administration (FAA) will study them to determine their effect on the navigable airspace. This will ensure that all usable airspace at and above 500 feet AGL is addressed during an aeronautical study and that this airspace is protected from obstructions that may create a hazard to air navigation.

2. Standards for voluntary marking of meteorological evaluation towers (METs), less than 200 feet above ground level (AGL), has been added to provide recommendations towards increasing conspicuity of these structures, particularly

for low-level agricultural flight operations. These standards include those for lighting and marking of the tower and associated guy wires.

3. A new Chapter 14, Aircraft Detection Lighting Systems, has been added to provide performance standards for these types of systems.

4. New lighting and marking standards are provided to reduce impact on migratory bird populations.

5. Medium-intensity white and medium-intensity dual obstruction light are now authorized on towers up to and including 700 feet AGL.

6. Editorial changes have been made.

Related Reading Material.

1. Advisory Circular 150/5345-43, Specification of Obstruction Marking and Lighting.

2. 14 CFR Part 77, Safe, Efficient Use and Preservation of the Navigable Airspace.

Application.

The FAA recommends the guidelines and standards in this AC for determining the proper way to light and mark obstructions affecting navigable airspace. This AC does not constitute a regulation and, in general, is not mandatory. However, a sponsor proposing any type of construction or alteration of a structure that may affect the National Airspace System (NAS) is required under the provisions of Title 14 Code of Federal Regulations to notify the FAA by completing the Notice of Proposed Construction or Alteration form (FAA Form 7460-1). These guidelines may become mandatory as part of the FAA's determination and should be followed on a case-bycase basis, as required Comments or Suggestions.

Direct comments or suggestions regarding this AC to:

Manager, Obstruction Evaluation Group Federal Aviation Administration ATTN: AJV-15 800 Independence Avenue, S.W.

Washington, DC 20591 Adis: McCattry Jodi S. McCarthy Director, Airspace Services

CONTENTS

Paragraph Page

CHAPTER 1. ADMINISTRATIVE AND GENERAL PROCEDURES1-1

1.1 Reporting Requirements1-1

1.2 Preconstruction Notice1-1

1.3 FAA Acknowledgement1-1

1.4 Supplemental Notice Requirement1-1

1.5 Modifications and Deviations1-2

1.6 Additional Notification1-3

CHAPTER 2. GENERAL2-1

2.1 Structures to be Marked and Lighted2-1

2.2 Guyed Structures2-1

2.3 Marking and Lighting Equipment2-1

2.4 Light Failure Notification2-2

2.5 Notification of Restoration2-2

2.6 Federal Communication Commission (FCC) Requirement2-2

2.7 Voluntary Marking of Meteorological Evaluation Towers (MET) Less Than 200 Feet

(61 m) AGL2-3

2.8 Obstruction Height Definition Changed to 499 Feet AGL2-3

CHAPTER 3. MARKING GUIDELINES3-1

3.1 Purpose3-1

3.2 Paint Colors3-1

3.3 Paint Standards3-1

3.4 Paint Patterns3-2

3.5 Unlighted Markers3-4

3.6 Unusual Complexities3-6

3.7 Omission or Alternatives to Marking3-6

CHAPTER 4. LIGHTING GUIDELINE4-1

4.1 Purpose4-1

4.2 Standards4-1

4.3 Lighting Systems4-1

4.4 Catenary Lighting4-2

4.5 Inspection, Repair and Maintenance4-3

4.6 Nonstandard Lights4-3

4.7 Placement Factors4-3

4.8 Monitoring Obstruction Lights4-4

4.9 Ice Shields4-5

4.10 Light Shields4-5

4.11 Distraction4-5

CHAPTER 5. RED OBSTRUCTION LIGHT SYSTEM5-1

5.1 Purpose5-1

5.2 Standards5-1

5.3 Control Device5-2

5.4 Poles, Towers and Similar Skeletal Structures5-2

5.5 Chimneys, Flare Stacks and Similar Solid Structures5-3

5.6 Group of Obstructions5-4

5.7 Alternate Method of Displaying Obstruction Lights5-4

5.8 Prominent Buildings, Bridges and Similar Extensive Obstructions5-4

CHAPTER 6. MEDIUM-INTENSITY FLASHING WHITE OBSTRUCTION LIGHT

SYSTEMS6-1

6.1 Purpose6-1

6.2 Standards6-1

6.3 Radio and Television Towers and Similar Skeletal Structures6-1

6.4 Control Device6-2

6.5 Chimneys, Flare Stacks and Similar Solid Structures6-3

6.6 Group of Obstructions6-3

6.7 Special Cases6-3

6.8 Prominent Buildings and Similar Extensive Obstructions6-3

CHAPTER 7. HIGH-INTENSITY FLASHING WHITE OBSTRUCTION LIGHT

SYSTEMS7-1

7.1 Purpose7-1

7.2 Standards7-1

7.3 Control Device7-1

7.4 Units per Level7-2

7.5 Installation Guidance7-2

7.6 Antenna or Similar Appurtenance Light7-3

7.7 Chimneys, Flare Stacks and Similar Solid Structures7-3

7.8 Radio and Television Towers and Similar Skeletal Structures7-4

7.9 Hyperbolic Cooling Towers7-4

7.10 Prominent Buildings and Similar Extensive Obstructions7-5

CHAPTER 8. DUAL LIGHTING WITH RED/MEDIUM-INTENSITY FLASHING WHITE

LIGHT SYSTEMS8-1

8.1 Purpose8-1

8.2 Installation8-1

8.3 Operation8-1

8.4 Control Device8-1

8.5 Antenna or Similar Appurtenance Light8-1

8.6 Omission of Marking8-2

CHAPTER 9. DUAL LIGHTING WITH RED/HIGH-INTENSITY FLASHING WHITE

LIGHT SYSTEMS9-1

9.1 Purpose9-1

9.2 Installation9-1

9.3 Operation9-1

9.4 Control Device9-1

9.5 Antenna or Similar Appurtenance Light9-1

9.6 Omission of Marking9-2

CHAPTER 10. MARKING AND LIGHTING OF CATENARY AND CATENARY

SUPPORT STRUCTURES10-1

10.1 Purpose10-1

10.2 Catenary Marking Standards10-1

10.3 Catenary Lighting Standards10-3

10.4 Control Device10-4

10.5 Area Surrounding Catenary Wire Support Structures10-5

10.6 Three or More Catenary Wire Support Structures10-5

10.7 Adjacent Catenary Structures10-5

CHAPTER 11. MARKING AND LIGHTING MOORED BALLOONS AND KITES11-1

11.1 Purpose11-1

11.2 Standards11-1

11.3 Marking11-1

11.4 Purpose11-1

11.5 Operational Characteristics11-2

CHAPTER 12. MARKING AND LIGHTING EQUIPMENT AND INFORMATION12-1

12.1 Purpose12-1

12.2 Paint Standard12-1

12.3 Availability of Specifications12-2

12.4 Lights and Associated Equipment12-2

12.5 Availability12-3

CHAPTER 13. MARKING AND LIGHTING WIND TURBINES13-1

13.1 Purpose13-1

13.2 General Standards13-1

13.3 Wind Turbine Configurations13-1

13.4 Marking Standards13-1

13.5 Lighting Standards13-2

13.6 Wind Turbines Above 499 Feet13-4

13.7 Wind Turbines at or Above 699 Feet (213 m)13-4

13.8 Lighting of Wind Turbines During Construction Phase13-5

13.9 Lighting and Marking of Airborne Wind Turbines13-5

13.10 Lighting and Marking of Offshore Wind Turbines13-5

CHAPTER 14. AIRCRAFT DETECTION LIGHTING SYSTEMS14-1

14.1 Purpose14-1

14.2 General Standards14-1

14.3 Voice/Audio Option14-3

APPENDIX AA-1

APPENDIX BB-1

1-1 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 NAS as required under the provisions of Title 14 Code of Federal Regulations (CFR) Part 77, Construction or alteration requiring notice, is to notify the Federal Aviation Administration (FAA) by completing the Notice of Proposed Construction or Alteration form (FAA Form 7460-1). This form should be filed electronically at http://oeaaa.faa.gov.

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, in writing, 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 http://oeaaa.faa.gov.

2. FAA Form 7460-2 Part 1 is to be completed and sent to the FAA at least 10 days prior to starting the actual construction or alteration of a structure. Part 2 shall be submitted within 5 days after the structure has reached its greatest height. The form should be filed electronically at http://oeaaa.faa.gov.

3. In addition, a supplemental notice shall be submitted upon abandonment of construction.

4. Letters are acceptable in cases where the construction/alteration is temporary or a proposal is abandoned. This notification process gives the FAA the necessary time to change effected procedures and/or minimum flight altitudes and to otherwise alert airmen of the structure’s presence.

Note: Notification, as required in the determination, is critical to aviation safety.

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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/or recommendations given, and should notify the FAA and FCC (for those structures regulated by the FCC) prior to removal of marking and/or lighting. A request received after a determination is issued may require a new study and could result in a new determination.

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 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 FAA Headquarters, OEG Manager, in Washington, DC, 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.

3. 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 on these systems is given in Table A-1 in Appendix A. While the FAA will make every effort to accommodate the structure sponsor’s request, sponsors should also request

1-3 information from system manufacturers to determine which system best meets their needs based on purpose, installation, and maintenance costs.

1.6 Additional Notification.

Any change to the submitted information on which the FAA has based its determination, including modification, deviation, or optional upgrade to white lighting on structures, may require notice to the FCC prior to making the change for proper authorization and annotations of obstruction marking and lighting. These structures 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 http://www.fcc.gov/forms.

Upon completion of the actual change, complete the “Add Supplemental Notice (7460-2 Form)” at the http://oeaaa.faa.gov website. You may also mail the FAA Form 7460-2 to:

FAA Aeronautical Information Services 1305 E W Hwy Silver Spring, MD 20910 1-800-626-3677

2-1 CHAPTER 2. GENERAL

2.1 Structures to be Marked and Lighted.

Any temporary or permanent structure, including all appurtenances, that exceeds an overall height of 200 feet (61 m) above ground level (AGL) or exceeds any obstruction standard contained in 14 CFR Part 77 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. In general, commercial outside lighting should not be used in lieu of FAA-recommended marking and/or lighting. Recommendations on marking and/or lighting structures can vary, depending on terrain features, weather patterns, geographic location, and in the case of wind turbines, the number of structures and overall design layout. The FAA may also recommend marking and/or lighting a structure that does not exceed 200 (61 m) feet AGL or 14 CFR Part 77 standards because of its particular location. The marking and lighting configurations are illustrated in Appendix A, Figures A-1 through A-27.

2.2 Guyed Structures.

The guys of a 2,000-foot (610-m) skeletal tower are anchored between 1,600 feet (488 m) and 2,000 feet (610 m) from the base of the structure. This places a portion of the guys 1,500 feet (458 m) from the tower at a height of between 125 feet (38 m) and 500 feet (153 m) AGL. Title 14 CFR Part 91, Section 119, requires pilots, when operating over other than congested areas, to remain at least 500 feet (153 m) from man-made structures. Therefore, the tower must be cleared by 2,000 feet (610 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 or 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. 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. Table A-1 in Appendix A contains descriptions of each FAA-approved obstruction lighting fixture that is referred to in this AC.

2-2

2.4 Light Failure Notification.

2.4.1 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.

2.4.2 Any failure or malfunction that lasts more than thirty (30) minutes and affects a top light or flashing obstruction light, regardless of its position, should be reported immediately by calling Outage Reporting and Notice to Airmen (NOTAM) 877-487- 6867, or for Alaska 800-478-3576, so a NOTAM can be issued. Lights that are voluntary (not required by an FAA determination) do not require a NOTAM. 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.

2.4.3 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, if known, prominent structures, landmarks, etc.).

4. Height of structure AGL/above mean sea level (AMSL) if known.

5. A return to service date.

6. FCC Antenna Structure Registration Number (for structures that are regulated by the FCC).

Note 1: When the primary lamp in a double obstruction light fails, and the secondary lamp comes on, no report is required.

Note 2: After 15 days, the NOTAM is automatically deleted from the system. The sponsor is responsible for calling outage reporting to extend the outage date or to report a return to service date.

2.5 Notification of Restoration.

As soon as normal operation is restored, notify outage reporting. 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.

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.

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2.7 Voluntary Marking of Meteorological Evaluation Towers (METs) Less Than 200 Feet (61 m) AGL.

2.7.1 Recommendation.

The FAA recommends voluntary marking of METs less than 200 feet (61 m) AGL in accordance with marking guidance contained in this advisory circular (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 it believes that voluntarily marking METs less than 200 feet (61 m) AGL in remote and rural areas enhance the conspicuity of these structures.

2.7.2 Painting.

METs should be painted in accordance to the criteria contained in Chapter 3, paragraphs 3.1 through 3.4, specifically, with alternate bands of aviation orange and white paint. In addition, paragraph 3.5 states that all markings should be replaced when faded or otherwise deteriorated.

2.7.3 High-Visibility Sleeves.

It is recommended that several high-visibility sleeves be installed on the MET’s outer guy wires. 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.

2.7.4 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 3, paragraph 3.5. 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 METs.

2.8 Obstruction Height Definition Changed to 499 Feet AGL.

Because of changes made to 14 CFR Part 77, Safe, Efficient Use, and Preservation of the Navigable Airspace, on July 21, 2010, the height of a structure (identified as an obstruction) was lowered to 499 feet AGL from 500 feet AGL. Consequently, all structures that are above 499 feet AGL will be designated as obstructions. The FAA will conduct an aeronautical study to determine the effect on navigable airspace. This will ensure all usable airspace at and above 500 feet AGL is addressed during the study and the airspace is safe for air navigation.