now, a letter to the biden administration asks for a delay in the rollout. the federal aviation administration warns potential interference could affect airline instruments, restrictions could ground flights stranding passengers as well as of course cargo. the letter goes on to say to be blunt, the nation s commerce will grind to a halt. late on monday, united airlines underscored the warning, saying the rollout could negatively affect more than a million united passengers. thousands of flights and goods and cargo traveling through 40 major airports every year. now, united also warned 5g signals near runways could interfere with safety equipment pilots use for takeoffs and landings really in bad weather. it said, we won t compromise on safety, full stop, as you can see there. at&t, cnn s parent company, and verizon declined to comment. let s get more on the story. ryan patel is a senior fellow at