US aviation safety regulators intend to require passenger and cargo aircraft to meet requirements by early next year for navigation gear to deal with potentially unsafe interference from 5G mobile-phone signals.

The equipment is needed because the newer wireless signals are on frequencies near those used by planes’ radio altimeters, which determine altitude over ground and can cause them to malfunction, the Federal Aviation Administration has found. Wireless companies are eager for a solution because they paid the government more than $80 billion for the new airwaves. The changes would need to be made by Feb. 1, 2024, the agency said in a notice Monday.

The FAA said it couldn’t rule out interference from 5G signals for about 100 incidents of aircraft navigation equipment issuing erroneous data. Such situations will increase as telecommunications providers expand 5G coverage throughout the US, the FAA said.

“Although they may seem minor in isolation such that some may consider them a mere nuisance, these warnings have safety implications over time,” the FAA said in its notice. “As the flightcrew becomes more desensitized to erroneous warnings, they are less likely to react to an accurate warning, negating the safety benefits of the warning altogether and likely leading to a catastrophic incident.”

Airlines “are working diligently to ensure fleets are equipped with compliant radio altimeters, but global supply chains continue to lag behind current demand,” said Airlines for America, the lobbying group representing the largest US carriers. “Any government deadline must consider this reality.”

Spokespeople for American Airlines Group Inc., United Airlines Holdings Inc. and Delta Air Lines Inc. didn’t immediately respond to requests for comment. 

The FAA estimates that out of 7,993 US-registered aircraft that would need revisions, approximately 180 would require radio altimeter replacements and 820 would require the addition of filters to comply with the proposed order, at an estimated cost of as much as $26 million.

CTIA, a trade group for the wireless industry, in an emailed statement called the FAA’s schedule for altimeter updates “reasonable and practical” and said that 5G “coexists safely with air traffic.” Members of the Washington-based organization include 5G providers AT&T Inc. and Verizon Communications Inc.