Wind Turbine FAQs (latest revision 10/11/2016) Tools: Printer graphicPrint this page
1. How should I submit my Wind Turbine and/or Met Tower Filing for aeronautical study?
All proposals for wind turbines and met towers regardless of whether they are on airport property or not should be filed as Off Airport Construction filings so they can be processed by the FAA's Obstruction Evaluation Group.
2. Is there a fee for obtaining a determination from the FAA?
No, there are no fees associated with any part of an aeronautical study or obtaining a determination from the FAA.
3. How do I know whether I'm required to file an FAA Form 7460-1, Notice of Proposed Construction or Alteration?
You may use the Notice Criteria Tool link on the home page to determine whether notice is required. The tool is based on Title 14, Code of Federal Regulations, Part 77 (14 CFR Part 77). There is a link to Part 77 on the home page of the website. Section 77.9 identifies construction or alteration requiring notice; Section 77.9(e) identifies construction or alteration not requiring notice.

If notice is required, you may submit the FAA Form 7460-1 electronically on the website. If you don't have an account for e-filing, there are instructions on the home page for setting up your account and e-filing the notice ("Click Here for Instructions on how to E-file your proposal with the FAA").
4. When should I submit my notice?
Because of the extensive studies that wind turbines require, we request that you file notice at least 90-120 days before planned construction. The aeronautical study process includes evaluations by various lines of business, and any identified impacts must be resolved before a final agency determination is issued. A public notice may be issued with a 30-day comment period, adding additional time to the aeronautical study. There is no guarantee that a final agency determination will be issued by your planned construction date, so file as early as possible. 14 CFR Part 77 does not carry provisions for waivers or exemptions, so there is no way to shorten or bypass this process. We also recommend that you provide early notice to DOD and DHS to determine if your proposal may impact their mission. Please see FAQ #23 – the FAA needs the exact location/height of each wind turbine along with specific information in order to evaluate any potential impacts to the National Airspace System (NAS).
5. What happens if I don't file notice for a structure that exceeds 14 CFR Part 77 notice criteria?
Notice is required by 14 CFR Part 77 is pursuant to 49 U.S.C., Section 44718. Persons who knowingly and willingly violate the notice requirements of Part 77 are subject to a civil penalty of $1,000 per day until the notice is received, pursuant to 49 U.S.C., Section 46301(a).
6. The airport manager and/or air traffic control tower manager said they don't have any objection to my proposal; do I still have to file an FAA Form 7460-1, Notice of Proposed Construction or Alteration?
Obtaining approval from the airport or air traffic control tower manager does not waive your requirement to submit the notice to the FAA if the structure exceeds the notice criteria of 14 CFR Part 77. You must receive a Determination of No Hazard to Air Navigation from the FAA and meet all conditions identified in the determination prior to beginning construction.
7. In what order should I submit the wind turbine proposals associated with my project?
Please submit them sequentially in the order of the wind turbine layout.
8. How do I submit attachments with my notice?
Select the Instructions link in the OE/AAA Account section and refer to the Attaching Documents Desk Reference Guide. (
9. What kind of documentation do you need in addition to the notices?
Please submit a spreadsheet identifying the ASN, the turbine ID number, latitude and longitude in degrees, minutes and seconds (NAD 83), site elevation, height above ground level (AGL), overall height above mean sea level (AMSL), and preferred marking and lighting (if you have a preference; please see the paragraph below concerning obstruction marking and lighting proposals). The FAA ASN number should be in ascending order when listed on the spreadsheet.

Please submit a map depicting the layout with the turbine number next to each site.

Please note the following concerning submission of obstruction marking and lighting proposals: You may submit a marking and lighting plan to the FAA with your proposed project, but it is not a requirement, and there is no guarantee that a submitted plan will be the plan outlined in any final determination. If you don't have a marking/lighting preference you may select "Other" in the "Requested Marking/Lighting" field, then type in "No Preference" in the "Other" field. The wind turbine specialist handling your studies will make the final determination concerning which structures should have obstruction lights based on guidance in FAA Advisory Circular 70/7460-1L, Change 1, Obstruction Marking and Lighting, Chapter 13. The determinations for those wind turbines that require obstruction lights will include a condition of WPSRL (white paint/synchronized red lights). The determinations for turbines that require daytime marking only will include a condition of WP (white paint only).

If you choose to submit a lighting plan, your plan must follow the guidance in FAA Advisory Circular 70/7460-1L, Change 1, Paragraph 13.5, LIGHTING STANDARDS, which states that obstruction lights should have unlighted separations of no more than 1/2-mile (804 m). Any submitted plan may or may not be considered, as the FAA specialist will apply the guidance in AC 70/7460-1L, Change 1, when determining the lighting scheme for your proposed wind farm.
10. If my proposal is on a military airfield do I file it as on airport or off airport property?
If the airfield is strictly military, proposals for temporary or permanent structures should be filed as off-airport structures. If the airfield is joint-use (military and civilian operations), proposals for temporary or permanent structures should be filed as on-airport structures. Any proposed changes to the pavement on an airfield (military or joint-use), i.e., construction/modification/resurfacing of runways, taxiways, aprons, etc. should be filed as on-airport proposals. ALL wind turbine proposals should be filed as off-airport.
11. What/who is the sponsor?
The sponsor can be you, your company, or your client. The sponsor is the person or business ultimately responsible for the construction or alteration. The sponsor appears as the addressee on all correspondence from the FAA.
12. I've received a Determination of No Hazard from the FAA, however, I am now in the process of selling the structure to someone else. How do I get the name on the determination changed to the new owner of the structure?
The FAA is not responsible for tracking changes in ownership. Therefore, if the FAA receives ownership changes it shall not make those corrections to issued determinations.

However, the original e-filer of the case can update the sponsor information through their registered e-filing account to reflect the new owner and ensure that the FAA has a means of contacting responsible parties with subsequent correspondence regarding the aeronautical study and determination.
13. How do I get the latitude and longitude?
The geographic coordinates may be obtained by utilizing a U.S. Geographical Survey 7.5 minute quadrangle map or equivalent, a GPS receiver or a certified survey. The coordinates should be accurate to within the nearest second or hundredth of a second. If a certified survey is available, please submit it with your filing.
14. What happens after I submit the notice and associated attachments?
An aeronautical study will be conducted by the FAA Air Traffic Organization, Obstruction Evaluation Group (OEG) for off-airport studies. The OEG technician will verify that the information submitted is accurate and complete. If the information is inaccurate or incomplete the technician will request additional information. If additional information is required for any of the studies within the project, none of the other studies will be processed until all required information has been received.

Once the technician has determined that all information is accurate and complete he will verify the studies in our system, which will change the status in your account to "Work in Progress." When the status is changed to "Work in Progress" your information is made available to other FAA offices and military representatives that need to review the proposal. Those offices will provide comments to the OEG and after all comments have been received, the OEG technician or specialist will issue the appropriate letter; when it's been issued the status in your account will change to "Determined." After the letter has been issued it will be available on the website. Select "Search Archives" and enter the ASN for a link to the study.
15. How do I request an extension of my determination?
Select the Instructions link in the OE/AAA Account section and refer to the Request Extension Desk Reference Guide. (
16. How do I know who to contact if I have questions about my proposal?
For proposals studied as off-airport structures, in the field entitled "If construction or alteration IS NOT LOCATED on an airport:" you may select the link at the bottom of that box, "QUESTIONS? Please contact the appropriate representative." Select the state in which the structure would be located. The contact information for the technician, backup technician and specialist assigned to that state for wind turbine (WT) studies will be provided.

For proposals on airport property, find the FAA Airports Region / District Office having jurisdiction over the airport on which the construction is located, and contact the office responsible for the state in which your structure would be located. Also, please contact that office with any questions pertaining to documents/sketches associated with on-airport structures that are e-filed.
17. I've received a Determination of No Hazard to Air Navigation for my structure. I've learned that the coordinates or height may be different than those noted in my determination. Am I required to file a new 7460-1 with the FAA?
A new study (7460-1) is required for any of the following changes: (a) The site elevation or height above ground level (AGL) increases by 1 foot or more, and/or (b) the latitude and/or longitude changes by exactly 1 second or more. For example: Initial latitude 37-00-50.00 – new study is not required for 37-00-49.01 to 49.99, or 37-00-50.01 to 37-00-50.99; a new study is required for 37-00-49.00 or 37-00-51.00. (c) A new filing is required any time there is a change to the frequencies or use of greater power. (d) A lighting study must be submitted if you would like to use marking/lighting other than what was stated as a condition on your determination letter.

If a new study is required based on a height increase or coordinate changes of 1 second or more, you must submit a New Case (Off Airport) prior to the start of construction so the FAA may evaluate your proposal at the revised height or location. If you do not file for a new study prior to the start of construction as required and you submit the Supplemental Notice (FAA Form 7460-2) instead, the system will recognize the changes and initiate a new study. When the new study is initiated you will be required to certify the new information and submit a new filing so the FAA may evaluate your structure under a new Aeronautical Study Number (ASN). NOTE: It is not a given that the proposal at the revised height or location will result in a favorable determination.

No new study is required for a height decrease only. In response to industry feedback, we changed our automated system to accept a height reduction when the Supplemental Notice (7460-2) is submitted. Any height revision that does not increase the height of the original proposal will be accepted. A corrected determination will be issued reflecting the reduced height. There is no time frame set for issuance of the corrected determination, but the OEG specialist/technician will issue it as soon as possible as workload allows.
18. Can I get a conditional determination so I can move forward with my proposal?
The FAA receives requests for conditional type determinations so that projects can obtain funding or be in compliance with production tax credit requirements, or for other reasons. It is our policy to have all outstanding issues resolved prior to issuing final agency determinations. When a no hazard determination is issued, the airspace for that structure is released. The FAA does not control land use issues and cannot issue determinations with conditions applicable to an event taking place in the future. We have no way to enforce or track these type of conditions and therefore cannot comply with requests for "conditional" type determinations.
19. The FAA issued determinations of no hazard for my project and I need to request an extension or file again. Am I guaranteed to get another determination of no hazard the second time around?
There is no guarantee that any project will get a determination of no hazard when it is studied again. The national airspace system is dynamic and changes must be taken into consideration during aeronautical studies. It is to your benefit to build the project during the eighteen months the determination is valid for.
20. How many extensions will the FAA grant?
After conducting a review, if no issues are identified that would cause a significant adverse effect, the FAA will grant one extension. After one extension is issued, if the structure has not been built, the FAA must receive a new filing and restudy the proposal.
21. When should I check Micrositing on my electronic filing?
If the wind turbines have moved no more than 500 feet from its original location, the case should be identified as micrositing when the case is electronically filed. Filing a proposal with “micrositing” does not guarantee that a favorable determination will be issued.

We will try to process the studies as quickly as possible. However, with 1,000 or more wind turbines filed each month, it is unreasonable and unrealistic to expect the FAA to stop working on other wind turbine cases and process your refilings. It is important to file as many wind turbines as possible in the correct locations.
22. We've received Determinations of No Hazard to Air Navigation for our wind farm. Now we want to refile for taller turbines. Can we keep the original determinations intact until the FAA issues new determinations?
If you refile for a height increase, your previous determinations will be terminated. It is our policy to terminate any previous determinations if you refile for a greater height. It causes an administrative hardship on the FAA to carry multiple filings at the same location. Other organizations that evaluate impacts cannot filter out the filings, and this creates a cumulative impact issue. With the multitude of wind turbine filings throughout the U.S., cumulative impact is based on the total number of turbines in an area. Multiple filings in the same location creates a cumulative impact issue that could result in erroneous data analysis. Additionally, obstruction evaluation specialists cannot work out an accurate lighting plan with multiple filings.

Wind turbine developers should work out necessary financial arrangements that are not dependent on maintaining an existing determination if refiling is necessary. It is not the responsibility of the FAA for any financial arrangements.
23. Can I submit my Wind Turbine Project to the FAA for a feasibility study?
Due to resource limitations, the FAA can no longer support feasibility studies or filings of a speculative nature for proposed Wind Turbine projects. The FAA must have all Wind Turbine configurations including latitude/longitude, height and layout plan at the time of your filing to accurately evaluate the cumulative effect of the entire project as it pertains to the national airspace system. Your proposal may warrant further detailed study including math modelling. Because of this, basic information on the wind turbine may be required (e.g., base width, base offset, nacelle length/radius).
24. How can I request termination of my study?
Select the Instructions link in the OE/AAA Account section and refer to the Request Termination-Dismantled-Abandoned Desk Reference Guide. (
25. How long is a Determination of No Hazard to Air Navigation issued for?
A Determination of No Hazard to Air Navigation will be valid for 18 months. This is the maximum time as specified by 14 CFR Part 77.
26. What does the large black turbine represent that appears on the map of the WIND TURBINE BUILD OUT TOOL?
By default, the Tool centers on an image of the entire United States. When the public user enters a set of latitude/longitude coordinates, the map is recentered on that location and shows all valid OE cases for wind turbines within a 48-nautical-mile circle around the entered point. The latitude/longitude is displayed as a large black wind turbine symbol to ensure the entered point remains visible to the user even if it represents a point in the middle of a wind turbine farm. The large black wind turbine symbol will always display in the middle of the image and represent the coordinates entered.
27. The Energy Information Administration (EIA) form requests the Federal Aviation Administration (FAA) Obstacle Number; where can this number be obtained?
The FAA’s Obstruction Evaluation Group has no control over what other agencies require and we do not store or provide obstacle numbers. If you are looking for Digital Obstacle File (DOF) numbers to use on EIA documents, please contact EIA Team Lead Glenn McGrath,
28. Can I file for wind turbines at or higher than 500 feet?
Yes- there is no restriction on heights for filing notice. File electronically on our website for your wind turbines at the highest height and the FAA will conduct an aeronautical study just like any other structure. Please note that at 500 feet or higher, your proposed structure will be in altitudes available to general aviation aircraft. A public notice may be issued to gather aeronautical information, and this includes a 30-day comment period.
29. Is the FAA working on a new lighting scheme for wind turbines that are 500 feet or higher?
Yes – the FAA is developing a new lighting scheme for wind turbines at or over 500 feet. This is necessary because general aviation altitudes start at 500 feet in the U.S. and it’s important for a pilot to detect wind turbines that exceed this threshold. This new lighting scheme will not be retroactive. However, if you have a determination from the FAA and have not built yet, we may revise the lighting plan.
30. Prior to a determination being issued, who can communicate with the FAA about a specific aeronautical study?
Communication with the FAA about a specific aeronautical study is allowed only for the sponsor and representative identified in the e-filing. Written permission can be uploaded to a study, or e-mailed to the specialist handling the study, by the sponsor or representative, identifying any individual authorized to communicate with the FAA about that specific study. The permission should include the individual’s name, phone number, and email address. In order to reduce confusion, we require a single point of contact for the aeronautical study.