By David Shepardson

WASHINGTON (Reuters), – Thursday’s notices by the Federal Aviation Administration will detail the impact that 5G wireless technology could have on the sensitive electronics of aircraft.

To reduce the potential impact of wireless services that will begin January 19, 2019, the FAA met with airlines, aircraft manufacturers and wireless carriers. FAA warns that interference can affect sensitive instruments such as altimeters.

AT&T (NYSE:) and Verizon Communications The NYSE:, which was awarded nearly all the C-Band spectrum last year in an auction worth $80-billion, agreed on January 3 to create buffer zones at 50 airports around the C-Band spectrum to minimize interference. A two-week delay in deployment was agreed, to avoid an aviation safety standoff.

The FAA said it will publish what are known as Notices to Air Missions at midnight Thursday offering details on “aircraft with untested altimeters or that need retrofitting or replacement will be unable to perform low-visibility landings where 5G is deployed.”

Notifications about the impact on major airports of instrument approaches will also be included. Certain GPS-guided approaches are still possible at airports such as Miami and Phoenix, according to the FAA.

The FAA said Wednesday that it “expects to provide updates soon about the estimated percentage of commercial aircraft equipped with altimeters that can operate reliably and accurately in the 5G C-Band environment.”

The wireless industry provided additional transmitter location data and the FAA said it was able to determine that in the initial 5G deployment, aircraft will be able to safely land in low-visibility conditions on some runways without restrictions.

The FAA is still “working to determine which radar altimeters will be reliable and accurate with 5G C-Band deployed in the United States.”

The FAA selected 50 U.S. Airports to be buffer zones for wireless carriers when they turn on 5G C band service.