Sean Duffy Says an L3Harris Team Was Switching FAA Lines From Copper to Fiber When the System Failed, Stock Drops After Hours

Transportation Secretary Sean Duffy said a team from L3Harris was working on an upgrade to the Federal Aviation Administration’s communications network when flights were halted after a network equipment failure.

According to Duffy’s remarks as reported by Yahoo Finance, the work involved switching FAA “lines” from copper wire to fiber optic connections. Fiber optic upgrades are commonly intended to improve bandwidth and reliability compared with older copper infrastructure.

Duffy said the outage occurred when a router “flooded” the air traffic control network, disrupting operations and leading to flight stoppages. In the description of the incident, Duffy linked the timing of the disruption to the period when an L3Harris crew was performing the changeover work.

The report tied the market reaction to the company’s role in the activity. L3Harris shares fell about 4.2% after hours following the remarks, according to the same account.

While the comments highlighted L3Harris involvement at the work site, the report did not provide details on the cause of the router failure, who was responsible for the specific equipment configuration that led to the network flooding, or whether the failure was directly related to the copper-to-fiber switching itself.

The company also did not, in the material cited in the report, publicly quantify damage, operational impacts, or costs associated with the disruption. It was also not clear from the account whether any FAA review or investigation had been initiated and what timeline would apply to any findings.