WASHINGTON (Reuters) — The Federal Aviation Administration (FAA) said Sunday that it had cleared an estimated 45% of the U.S. commercial airplane fleet to perform low-visibility landings at many airports where 5G C-band will be deployed starting Wednesday.

The FAA said it approved two radio altimeter models installed in a wide variety of Boeing and Airbus planes, including some Boeing 737, 747, 757, 767, MD-10/-11 and Airbus A310, A319, A320, A321, A330 and A350 models, just days before AT&T and Verizon launch new 5G service Wednesday. The FAA said it expects to issue more approvals in the coming days.

The FAA said the aircraft and altimeter approvals open “runways at as many as 48 of the 88 airports most directly affected by 5G C-band interference.” But the agency warned that “even with these new approvals, flights at some airports may still be affected.”