On December 7, The Federal Aviation Administration issued an airworthiness directive(AD) which requires Helicopter and passenger aircraft to prohibit certain operations which require a radio altimeter data, when there is the presence of 5G wireless transmission.
Radio Altimeter is a device that measures altitude above the terrain presently beneath an aircraft or spacecraft by timing how long it takes a beam of radio waves to travel to the ground, reflect, and return to the craft.
Commuter-category aircraft (Aircraft that travel from a small regional airport to the main airport), including all helicopters equipped with RadAlts, will have to follow his new directive. The FAA states, “Radio altimeters cannot be relied upon to perform their intended function if they experience interference from wireless broadband operations in the 3.7-3.98 GHz frequency band.”
Operators should now review their aircraft’s flight manual to restrict using RadAlts in areas of 5G influence which NOTEAMs identify (Notices for Airmen). Airports where the use of radio altimeter is not dependable will be issued to NOTAMs. Use of Instrument landing system(ILS), Required navigation performance( RNP), Automatic Landing Operations and Head-up display (HUD), or Enhanced flight vision system (EFVS), which are essential instruments for a pilot, can fall under prohibited operations.
Although the deployment of the 5G network was planned to start on December 5, telecommunication companies like AT&T and Verizon will now deploy them one month later, on January 5, 2022, as per FAA’s request. A proposal was submitted to FCC (Federal Communications Commission) to lower the problems by reducing the power levels at various 5G stations around airports and heliports.
Andrew Roy, Director of engineering services with Annapolis, said that the telecommunications companies still haven’t provided maps of 5G tower locations.
He added, “There was a comment from the AT&T CEO the other week, who said that for the proposal Verizon and AT&T had put forward, his estimate was that it was single digits—maybe even less than that—as a percent of total [5G] towers that would be affected by this. Certainly, from the 5G perspective, we don’t think it’s a major issue to start considering, at least around airports. Obviously, the helicopter concern is still there.”