HARRISBURG, Pa. (WHTM) — Don’t celebrate just yet.

That’s the message from the Regional Airline Association, which represents airlines that operate most of the flights at Harrisburg International Airport, amid evidence that the threat of operational chaos related to the debut of 5G cell phone towers could be abating.  

As at many mid-sized airports, most aircraft carrying the logos of American, Delta, and United are actually flown by what are called “regional airlines” with names like SkyWest and Republic, which fly under contract for the “mainline” airlines.

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“So far our carriers are saying this hasn’t gone nearly as far as they thought it would be compared to some of the relief the mainlines have gotten,” said Faye Malarkey Black, president, and CEO of the Regional Airline Association. “They’re a little bit more restrictive. We’re declaring victory prematurely here. There’s a significant part of the fleet for which there has not been an approval.”

In its latest round of approvals Thursday, the FAA said it had approved 78 percent of the total U.S. commercial airline fleet to operate near 5G cell phone towers, based on the altimeter models in their cockpits. Yet an abc27 News analysis of Cirium schedule data Friday found 79 percent of flights service Harrisburg are on aircraft that aren’t yet fully approved.

The FAA has approved nearly all full-sized mainline aircraft but not yet most regional jets.

AT&T and Verizon turned on new fast 5G cell towers across the country on Wednesday, Jan. 19, and almost all of them are not an issue. However, airlines and the FAA that the ones near airports could interfere with cockpit equipment, specifically the altimeter that measure how high off the ground airplanes are.

What does the lack of full approval mean for regional jets?

“It is going to depend on the weather,” Black said. “In the event we have a weather scenario to that extent, a lot of the operations into those airports, both big and small that don’t have special approvals to operate with these 5G interferences, they will be grounded, they will be diverted, they won’t take off at their originator airport, they’ll be delayed. There will be massive chaos for the passengers that rely on them.”

The lack of chaos so far, she said — and airline sources agreed — is due partly to the relatively benign weather in the U.S. the past couple of days. On the other hand, the chaos might never materialize if the FAA approves the as-yet unapproved aircraft and airports before visibility becomes low enough at impacted airports to cause increased diversions.

Diverting flights because of weather conditions is a common procedure for pilots. However, with the recent 5G rollout, pilots on some aircraft near some airports can feel forced to be more cautious than usual and divert to another airport — inconveniencing passengers and crew — when normally they might have been able to land at their original destination.