interfere with the altimeter just when pilots need it most. with the system going live tomorrow the airline ceos have written this letter asking that the 5g sites within two miles of airports remained turned off for now, warning that immediate intervention is needed to avoid significant operational disruption to air passengers, shippers, supply chain and delivery of needed medical supplies. >> the faa is uncomfortable with the safety risk and as a consequence the impact on our operations to mitigate that would be a significant set back. >> reporter: concerned about potential interference the faa has already issued a notice to pilots. as 5g goes live wednesday, the faa will prohibit pilots from using altimeters during landing at more than 80 airports near 5g sites, including large airport hubs in dallas, new york, chicago and seattle. if those airports experience bad weather the ceos warn the vast