Your browser is out-of-date!

Update your browser to view this website correctly. Update my browser now


FAA Updates ‘Navigable Airspace’ Rules

Question of frequency notification for FM band remains unresolved in Part 77 revision

Those who own or plan towers, take note: The Federal Aviation Administration and the Department of Transportation have updated federal rules concerning the “Safe, Efficient Use and Preservation of the Navigable Airspace.”

The change has been published in the Federal Register, amending regulations governing objects that may affect areas where aircraft may be. It takes effect in January.

“These rules have not been revised in several decades, and the FAA has determined it is necessary to update the regulations, incorporate case law and legislative action, and simplify the rule language,” it wrote. “These changes will improve safety and promote the efficient use of the National Airspace System.”

The tweaks were based on a notice of proposed rulemaking issued in 2006 in which the FAA proposed to establish notification requirements and obstruction standards for transmitting on certain frequencies and to require proponents to file a notice of planned construction or changes in structures near certain private airports.

One area of interest to radio stations — and left unresolved — is frequency notification.

The original proposal called for notice to be filed with the FAA for any construction or modification of facilities, including antenna structures, for transmitting in various frequency bands including 54–108 MHz; FM stations reside within that range. It also proposed notification requirements for changes in things like frequency, antenna pattern and ERP.

The FAA noted, “It is critical for the agency to be notified of pending construction of physical objects that may affect the safety of aeronautical operations” and that electromagnetic transmissions can cause problems for flight avionics and other systems. “FM broadcast service transmissions operating in the 88.0–107.9 MHz frequency band pose the greatest concern to FAA navigation signals.”

However, it continued, “FAA, FCC and NTIA are collaborating on the best way to address this issue. A resolution of this issue is expected soon.” Thus its proposals on FM transmissions in 88–107.9 MHz remain pending.

“The FAA will address the comments filed in this docket about the proposed frequency notice requirements and proposed EMI obstruction standards when a formal and collaborative decision is announced.”

Read the full rule change (PDF).