Radar screens at New Jersey's Newark Liberty International Airport went black again early Friday morning. The outage happened at 3:55 a.m. and lasted about 90 seconds, the Federal Aviation Administration said.

Newark Liberty International Airport suffered another brief air traffic control outage Friday morning, the FAA confirmed.

Duffy laid out an extensive plan to replace the nation’s outdated air traffic control system last week, including installing 4,600 new high-speed data connections and replacing 618 radars, but didn’t put a price tag on the plan other than to say it will cost billions.

The air traffic control mishap early Friday morning added to disruptions in recent days that have intensified concerns about safety at one of the busiest U.S. airports.

Newark Liberty International Airport in New Jersey has been dealing with nonstop delays and flight cancellations due to outdated equipment and air traffic control understaffing across the U.S.

Travel woes at Newark Airport continued Monday after a weekend featuring another radar outage, a ground stop and dozens of flight cancellations and delays. The FAA announced Newark was operating on a ground delay program,

Sen. Andy Kim, a New Jersey Democrat, said the FAA is not being transparent enough after visiting air traffic controllers in Philadelphia and Newark.

Newark approach lost radar and comms with at least 16 commercial jets. Many circled in oval loops before landing elsewhere. A CNN data analysis reveals the ripple effects from the outage.