Verizon and AT&T have volunteered to limit their 5G networks in an effort to address concerns over air traffic safety.

Verizon and AT&T spent a small fortune — to the tune of nearly $69 billion — to purchase C-Band spectrum for their 5G networks. C-Band, falling in the mid-range of available spectrum, is considered the sweet spot for 5G, offering a solid blend of speed, range and penetration.

Unfortunately, the spectrum Verizon and AT&T purchased is in the 3.7 to 3.98 GHz range, relatively close to the 4.2-4.4 GHz range that airline altimeters run on. As a result, there have been concerns that Verizon and AT&T’s 5G could negatively impact airline safety, leading both companies to delay their C-Band rollout.

Verizon and AT&T are now voluntarily offering to limit their rollout of the C-Band 5G spectrum in an effort to mitigate potential issues.

“We have voluntarily agreed to certain precautionary protection measures for 5G networks in the C-band while additional evidence from radio altimeter manufacturers is evaluated,” AT&T said in a statement, according to The Hill. “Though there is no credible evidence that a legitimate interference problem exists, we agreed to take these additional steps to alleviate any safety concerns from the FAA.”

Despite their willingness to cripple their 5G, as Telecoms.com points out, it’s obvious by the wording of their statement that Verizon and AT&T are not happy with the current state of affairs. Their statement is a not-so-subtle way of pointing out that, after spending tens of billions, they shouldn’t have to take the steps they’re taking.

“Wireless carriers, including AT&T and Verizon, paid over $80 billion for C-band spectrum—and have committed to pay another $15 billion to satellite users for early access to those licenses—and made those investments in reliance on a set of technical ground rules that were expressly found by the FCC to protect other spectrum users.”

Verizon and AT&T’s issues are yet another win for T-Mobile, which has already established itself as the 5G leader in the US market. T-Mobile’s mid-band spectrum falls in the 2.5 GHz range, which is still in the sweet spot for 5G but far enough away from the spectrum airline altimeters use to not be a concern. As a result, T-Mobile has been unaffected by the issues Verizon and AT&T are facing.