Airplane mechanics are still looking at the two planes trying to determine what the problems were, she said.
Passenger Alex Brown said he heard the loud banging during the second flight.
“It was like someone dropping a lead ball on the floor,” he told Channel 2. “And (a Delta official) came back on and said we’re going to turn around. Everything is OK with the airplane but ... we’re going to turn around” as a precaution.
Delta put Brown and other passengers in a hotel.
They are now scheduled to fly out of Atlanta at 6 p.m.