WASHINGTON: "As the commercial airline and telecommunications industries scramble to limit the potential safety risks to aircraft from a rollout of new 5G networks, it may be months before the U.S. military has a handle on whether, or how big, of a problem this might be for its own planes. At the center of the controversy is whether the deployment of 5G networks, operating along a frequency known as the C-band, will interfere with radar altimeters used by military, civilian and commercial aircraft and helicopters. These altimeters are used to measure the distance between the aircraft and the ground. For the military, they are particularly necessary when mobility aircraft such as cargo planes or tankers land in adverse weather conditions. If the pilot’s visibility is poor during such a landing, he or she would have to use altimeters to measure how far off the ground the aircraft is during the approach, and a flawed reading could lead to a crash. The military decided about a year ago that instead of trying to block the auction of the C-band spectrum, it would work to limit the potential interference with its aircraft’s systems.

In a Tuesday email, Air Force spokesman Capt. Patrick Gargan said the Defense Department is working with its FAA counterparts on the 5G issue. Gargan also said military services have issued bulletins to the field and to fleets to alert aircrews about the potential for interference, and is setting up a system for reporting interference if it happens."

https://www.defensenews.com/air/2022/01/19/military-may-take-months-to-gauge-5g-safety-risks-to-aircraft/