United Airlines CEO Scott Kirby is warning that Verizon and AT&T’s 5G rollout would be catastrophic for the airline industry.

Verizon and AT&T spent over $68 billion on C-band spectrum for their 5G networks. C-band spectrum is squarely in the mid-band range, making it ideal for 5G. Unfortunately, the spectrum is very close to the same frequencies airline altimeters use. Although T-Mobile spent $9 billion, it was largely to fill out its existing spectrum, spectrum that poses no danger to the airline industry. Verizon and AT&T, in contrast, delayed their rollout of the new spectrum before agreeing to throttle back the power in an effort to avoid issues.

Unfortunately, Kirby doesn’t think that will be enough. According to The Independent, Kirby warned Congress in a US Senate Commerce Committee meeting, that the C-band rollout “would be a catastrophic failure of government.”

Not everyone agrees Kirby’s fears are warranted, with the Cellular Telecommunications Industry Association (CITA) saying concerns about interference amount to fear-mongering.

“The aviation industry’s fear-mongering relies on completely discredited information and deliberate distortions of fact,” says CTIA.

At the same time, Kirby was quick to point out the consequences of the FAA’s new directive aimed at addressing the 5G issue, in which the agency prohibits the use of altimeters in low-visibility conditions.

“Unless something changes – we will not be able to use radio altimeters at 40-something of the largest airports in the country,” Mr Kirby said. “It is a certainty. This is not a debate.”

The debate between 5G and the airline safety looks to be far from over, but one thing is clear: Until the issue is resolved, airline passengers will likely experience more delays as the industry accommodates the FAA’s new directive.