Operators of some Boeing planes are now being directed by the Federal safety officials to adopt extra procedures when landing on wet or snowy runways near impending 5G services due to interference from the wireless networks.

The FAA made this known on Friday that interference could delay systems like thrust reversers on Boeing 787s from kicking in which could leave the plane’s brakes to slow down.

That “could prevent an aircraft from stopping on the runway,” the FAA said.

A report has it that similar orders could be issued by the FAA in coming days for other planes as well. The FAA has therefore required both Boeing and Airbus to provide information about many of their aircraft models.

Boeing on the other hand said it was working with suppliers, airlines, telecom companies, and regulators in order “to ensure that every commercial airplane model can safely and confidently operate when 5G is implemented in the United States.”

This order came a day after the FAA started issuing restrictions that airlines and other aircraft operators will face at many airports when AT&T and Verizon will launch their new, faster 5G wireless service.

However, the agency has continued to study the impact of these wireless networks on altimeters, an instrument that measures an aircraft’s height above the ground. Data gathered from altimeters are then used to help pilots land when visibility is poor.

The devices operate on a portion of the radio spectrum that is close to the range used by the new 5G service, called C-Band.

This action has been one part of the much larger disagreement between the aviation regulatory agency and telecom companies with the latter in collaboration with the Federal Communications Commission (FCC) saying that 5G networks do not pose threats to aviation.

FAA on the other hand isn’t buying this and stating that more researches need to be conducted in order to understand the impact of 5G on aviation.

The FAA, therefore, announced that it was conducting tests in order to learn how many commercial planes have altimeters that might be vulnerable to spectrum interference.

The agency said this week it expects to estimate the percentage of those planes soon, but didn’t put a date on it.

“Aircraft with untested altimeters or that need retrofitting or replacement will be unable to perform low-visibility landings where 5G is deployed,” the agency said in a statement.

The order regarding Boeing 787s covers about 137 planes in the United States and 1,010 globally. The Boeing 787 model is a two-aisle plane popular on longer routes, including international trips.

The FAA said that based on information from Boeing, the 787s might not shift properly from flying to landing mode if there is interference, which could delay the activation of systems that help slow the plane.

A while back, both Verizon and AT&T agreed to postpone the activation of their new networks due to concerns raised by aviation groups and the FAA, most recently after the FAA and Transportation Secretary Pete Buttigieg weighed in on the aviation industry’s side. Buttigieg and FAA Administrator Stephen Dickson warned that flights could be canceled or diverted to avoid potential safety risks.

However, both telecom companies and the FAA reached an agreement whereby some 50 airports will have buffer zones in which the companies will turn off 5G transmitters or make other relevant changes in order to limit potential interference through early July.

The 50 include the three major airports in the New York City area — LaGuardia, JFK, and Newark Liberty — O’Hare and Midway in Chicago, Dallas/Fort Worth International, Bush Intercontinental in Houston, Los Angeles International, and San Francisco.

That concession by the telecoms was modeled after an approach used in France, although the FAA said last week that France requires more dramatic reductions in cell-tower reach around airports.