Thousands of flyers had their travel plans disrupted Monday after the Federal Aviation Administration ordered a ground stop at Newark Liberty, Teterboro and Philadelphia airports.

Dozens of planes were left idling on runways while the FAA said it was contending with a technology breakdown at Philadelphia’s Terminal Radar Approach Control, or TRACON, facility.

The ground stop at Newark began shortly after 10 a.m. — after the ground stops at Teterboro and Philadelphia went into effect.

The result was departure delays of up to 150 minutes out of Newark and Philadelphia, according to the FAA’s website.

The FAA said in a statement that the problem was an issue with “some frequencies” but didn’t say how long it would take to get the systems back up and running.

“The FAA is pausing flights into Philadelphia International, Teterboro and Newark Liberty International airports due to issues with some frequencies at Philadelphia TRACON,” the statement said.

This is one of the heaviest air travel corridors in the country, and last year an equipment malfunction left about a dozen planes flying blind for 90 seconds in the crowded skies over New Jersey.

Transportation Secretary Sean Duffy insisted at the time that there was never any danger of planes colliding during that brief communications breakdown.