The chief executives of major US passenger and cargo airlines have warned of a "catastrophic" aviation crisis this week as AT&T and Verizon deploy new 5G services.

They said the new C band 5G service set to begin on Wednesday (Jan 19) could render a significant number of aircraft unusable, causing chaos for US flights and potentially stranding tens of thousands of Americans overseas.

Here is the background to the dispute:

What happened?

The United States auctioned mid-range 5G bandwidth to mobile phone companies in early 2021 in the 3.7-3.98 GHz range on the spectrum known as...