After several delays, AT&T and Verizon are set to roll out national 5G service in the U.S. on Wednesday, 19 January, with the exception that the service would, for the moment, not be activated within a two-mile radius of some important airports. This agreement was in response to concerns from airlines and federal regulators that C-band 5G signals could interfere with the altimeters of commercial aircraft.
Mobile operators have long insisted that 5G networks would not interfere with airlines’ navigational equipment. Nonetheless, AT&T and Verizon agreed to pause the rollout in the vicinity of certain airports—determined by the Federal Aviation Administration—after airline executives sent a letter to the Biden administration saying that the presence of 5G poses such a serious threat to air safety that the “nation’s commerce will grind to a halt.” President Biden said, “This agreement will avoid potentially devastating disruptions to passenger travel, cargo operations and our economic recovery.” The agreement will affect approximately 10 percent of the 5G rollout, and the operators did not announce how long the delay in deployment would last.
Despite the agreement, as Tuesday came to an end there was uncertainty over whether it would be enough to avert major disruptions in air service on Wednesday. Several international airlines, including Air India, Emirates, Japan Airlines and All Nippon Airways, said they would cancel flights to the U.S. on Wednesday. As for domestic airlines, the FAA said that it had cleared 45 percent of U.S. commercial planes to land at airports in the presence of 5G, using updated guidance on the use of altimeters; among the other 55 percent, there remains the prospect of chaos on Wednesday and afterward, at least when landing at airports other than those covered in the agreement.
As we reported in these pages, the FAA and airline executives have been warning for months that there could be problems with 5G and navigation. In early November, the MNOs agreed to pause their 5G rollouts, which had been due to begin in early December, for one month. Now it is two weeks past that, and still the rollout is set to proceed in an incomplete manner, with concerns and controversy ongoing. This situation is frustrating for operators and is likely to cast a shadow over the much-anticipated launch of the new high-speed network technology.
Give that there was ample time to investigate and resolve the issues, it is unfortunate that matters have come to this pass. MNOs asserted that the fact that C-band 5G and aircraft altimeters operate over similar—not identical—frequencies does not create a safety risk. Nonetheless, an abundance of caution in light of the high stakes has led to a lack of confidence in these assertions on the part of regulators and airline officials.
From the MNOs’ point of view, the fact that 90 percent of the rollout is moving forward is a good thing, considering that there had been a possibility that the entire rollout would have to wait for the altimeter question to be settled. Nonetheless, the situation in the U.S. is in stark contrast to what has been happening in other markets where there has been no controversy over air safety. For example, on Tuesday, the Norwegian regulator said that it had received no reports of 5G signals interfering with air navigation, adding that the 5G networks being developed in Norway and elsewhere in Europe use frequencies that are farther away from those used by altimeters than is the case in the U.S.