5G may cause system failure in aircraft navigation.US and Japanese airlines already cancelled flights.

Two major US cellphone carriers, AT&T and Verizon, agreed Tuesday afternoon to delay the planned roll-out of some new 5G wireless service that was intended to go into full operation tomorrow, Wednesday 19.

This comes after many US airlines like American Airlines, Delta Air Lines, United Airlines and Southwest Airlines raised alarms about potential interference with important systems on planes. In a letter to the White House, airline CEOs asked the government for “immediate intervention,” warning that the deployment of 5G could result in massive flight disruptions nationwide.

The US Federal Aviation Administration (FAA) is concerned about a narrow range of frequencies included in the package of radio frequencies used for 5G services. These frequencies should provide higher data speeds and make cellphones more reliable. But airline CEOs worry that cellphone towers on the ground emitting a 5G signal could interfere with an airplane’s altimeter.

Other than some European 5G mobile communications standard, the US based 5G standard is using a frequency above 3,7 Gigahertz which is dangerously near the operation frequency of radar altimeters (4,2 - 4,4 Gigahertz), needed for aircraft approach navigation at low altitude and low visibility.

All Nippon Airways (ANA) and Japan Airlines (JAL) announced on the evening of the 18th that they had cancelled some flights between Japan and the United States due to the possible impact of the 5G signal in the United States. The Federal Aviation Administration and several airlines have previously warned that 5G airwaves could cause malfunctions in aircraft instruments and systems.

The Japanese press reported that two Japanese airlines flying Boeing 777s on the America Line will cancel flights that cannot be changed to other models. All Nippon Airways pointed out that it learned from Boeing on the 18th that due to the influence of 5G radio waves, the system that controls the posture of the 777 aircraft may malfunction when it is flying at low altitudes.

5G恐致系统故障 全日空和日航取消部分飞美航班

According to ANA, U.S. aviation authorities pointed out in December that 5G airwaves could affect the plane's altimeter, and on Jan. 13 revealed the airports that might be affected. Boeing notified all airlines operating its 777s to limit operations because it could affect airframe control as the planes land. JAL also canceled some flights due to this impact.

Warnings from Boeing were accompanied by similar declarations from Airbus Industries.

The Arabic air carrier Emirates grounded its flights bound for North America.