The Boeing 767, carrying 9 crew members and 226 passengers, was on its way to Atlanta. Pilots had to turn around due to a problem with the left engine, according to Delta.
Delta flight 446 landed safely, and the plane taxied to the gate on its own with no sign of a fire at that point. Passengers were able to deplane normally.
Firefighters examined the aircraft as a safety precaution.
An investigation is now underway to determine what went wrong.
Delta said customers were reaccommodated on a new aircraft to their final destinations.