WASHINGTON — On Wednesday, two senators from the United States demanded that officials provide a comprehensive list of airlines that may fail to meet the deadline to retrofit their planes to prevent any potential interference with the 5G wireless network.

The senators have urged swift action to ensure that all necessary measures are put in place to avoid any potential safety risks. Republican Senator Marsha Blackburn and Democratic Senator Ben Ray Lujan said many airlines could not fulfill the required measures before the upcoming deadlines.

Acting head of the Federal Aviation Administration (FAA), Billy Nolen, and Transportation Secretary Pete Buttigieg received a letter from two senators requesting information on the specific airlines that could potentially be affected by the 5G wireless interference issue.

"We are concerned that airlines that do not meet the retrofit deadlines could negatively impact consumers - both due to flight cancellations or delays and by impeding access to needed connectivity," the letter noted.

"We have identified a risk that must be addressed. We believe we have given the right amount of time to do that, so we have no plans at this point to change the timing," Nolen told Blackburn during a hearing on Wednesday.

International Air Transport Association (IATA) Director General Willie Walsh said that many US carriers could not meet required measures due to supply chain issues, certification delays, and inevitable logistical challenges.

Last year, concerns were raised regarding the potential for 5G wireless service to interfere with airplane altimeters. These devices are essential for determining the altitude of an aircraft and are particularly important during poor weather conditions. Disruptions were reported at several U.S. airports involving international carriers, prompting action to be taken.

In June 2022, both Verizon and AT&T voluntarily agreed to delay some C-Band 5G usage until July 1, 2023, allowing air carriers time to retrofit their aircraft to prevent interference. The Federal Aviation Administration (FAA) has also proposed that airlines revise their flight manuals to prohibit low-visibility landings after June 30 unless the necessary retrofits have been completed.

Earlier this year, the Federal Aviation Administration (FAA) put forward a proposal to mandate the use of 5G C-Band-tolerant radio altimeters or approved filters for all passenger and cargo planes in the United States. The proposal aims to be implemented by early 2024 and is intended to ensure that aircraft remain safe and free from any potential interference with the 5G wireless network.

Why is this not an issue elsewhere other than the United States?

In 2019, the European Union established new standards for mid-range 5G frequencies in the 3.4-3.8 GHz range, which is away from the spectrum (4.2-4.4 GHz) used for altimeters in the commercial aircraft. The frequencies identified by the EU are lower than those set to be introduced in the United States.

To fully leverage the capabilities of 5G technology, the American 5G service providers aim to operate at higher frequencies . This is because the higher the frequency, the faster the service.

Since the commercialization of 5G mobile communication in South Korea back in April 2019, the 5G frequency band has been set at 3.42-3.7 GHz, and no cases of radio wave interference have been reported so far.