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Antenna Structure Registration - Help

This article provides information on Modifying a Registration in the Antenna Structure Registration (ASR) system. You would modify a registration to change technical data about the structure. To file a Modification to an Antenna Structure Registration (ASR) the tower must be in a Constructed status. The FCC put this restriction in place to promote air safety by ensuring that a notice of construction can only be filed against an approved registration record. If the tower is constructed and you have not filed the required notification, you must do so prior to filing your modification.

Major Modifications will require Environmental Notification. The following changes are considered to be Major Modifications:

  1. Increasing Overall AGL Height by more than 20 feet (6.1 m), or by more than 10% of the total tower height, whichever is greater.
  2. Submitting an environmental assessment
  3. Changing the registered lighting to a less-preferred lighting style
  4. - Ranking of FAA lighting styles, from most preferred to least preferred:

    1. No lights
    2. No red steady lights
    3. Red steady lights

    The following changes are considered to be Minor Modifications and do not require Environmental Notice:

    1. Administrative Changes
    2. Updating the FAA Study Number
    3. Correcting Coordinates (The tower is not physically moving)
    4. Lowering the Overall AGL Height
    5. Changing registered lighting to a more preferred lighting style

    Steps to Filing a Request to Modify a Registration in ASR

    1. Log in to ASR Online Filing with your FCC Registration Number (FRN) and password.
    2. On the Antenna Structure Registration Dashboard click on the drop-down arrow on the More Actions button.
    3. Select the purpose Modify Registration.
    4. On the Registration Manager page click on the registration number you would like to modify.
    5. On the Registration at a Glance page click on the Modification button.
    6. Complete the required fields. Navigate through the application by clicking on the Save and Continue button.
    7. On the Application Summary page click on the Sign and Submit button.
    8. Complete the Certification page and click the Submit Application button.
    9. You will receive a confirmation of application submission screen that shows the file number and status. Click the Back to Home button to return to the Antenna Structure Registration Dashboard.

      Note: If your application requires environmental notice, you will need to sign and submit the application both when you complete Part I prior to environmental notice and again when you return to the application to complete Part 2.

    FAQs – Filing a Request to Modify a Registration in ASR

    Will I owe a filing fee?


    Why can’t I see the registrations I want to update in step 4?

    There are a few possibilities:

    • Registrations must be in a Constructed status in order to file a modification. This policy is in place to promote air safety. If you need to modify a tower prior to it being constructed, you will need to cancel the existing tower registration and file a new tower registration.
    • The registration must be linked to the same FRN you used to log in to ASR Online Filing.
    • If you previously started to file a modification application and did not complete the filing, it could be in a list of Saved applications.

    How do I know when my application is ready for the Part Two Certification?

    Applications could be ready for the Part Two Certification as soon as 10-12 days after the 30-day National Notice Period, as long as no further environmental review is required, or if a FONSI letter has been issued.

    To check if the application is ready for the Part Two Certification, Log in to ASR Online Filing with your FCC Registration Number (FRN) and password. From the Antenna Structure Registration Dashboard, click the My Applications tab. On the Application Manager page click on the Env. Certification tab. The application file number will appear here if it is ready for certification.

    How do I know if my application is received at the FCC?

    Refer to the instructions on filing the Part Two Certification.

    Applications will appear immediately in ASR Application Search. Enter the file number in the ASR Application Search to find your application.