The temporary holdup is to address the overlapping of air-safety distress frequencies that may interfere with pilots.
“Here’s the problem, the problem is that the radar altimeter that bounces a signal off the ground, they operate on near the same frequency as 5G,” said Dennis Glaeser, an Aerospace Engineer and Certified Flight Instructor. “And so, at the outer edge of these frequencies, there’s an overlap.”
And then, there is interference with the signal; the concern is that the pilot could get a false indication of the plane’s proximity to the ground when landing.
“It’s like getting interference on your AM radio when you’re driving past those power lines,” Glaeser said. “The 5G could give you bad readings.”
Experts say the vast majority of the time that pilots don’t rely on radar altimeters. But they are critical when a commercial pilot is landing in bad weather with low visibility.
“So, if you’re landing in poor conditions and you’re depending on your radar altimeter, and there happens to be 5G nearby, and there’s interference, that could cause a problem,” Glaeser said.
This is an issue unique to U.S. airspace.
In 2019, the European Union set standards for mid-range 5G frequencies which is lower than the service set to be rolled out in the U.S.
DTW is one of the 50 airports that will have buffer zones when wireless companies implement the new 5G C-band service this month.
Over the next six months, the Airport Authority looks forward to receiving additional information from the FAA regarding the effectiveness of these buffer zones to mitigate potential impacts of 5G interference and guidance regarding the next steps when the mitigation measures expire.