FAA Investigates Two Southwest Engine Issues

The US Federal Aviation Administration is investigating engine problems that grounded two Southwest Airlines planes at Chicago's Midway Airport this week.

There were no injuries in either incident, a Southwest spokeswoman said.

The FAA is looking into both cases, in which Southwest reported issues with an engine, an FAA spokeswoman said.

Southwest said in a statement that 136 passengers evacuated on Friday and travelled to Philadelphia on a different aircraft, arriving about two hours behind schedule.

Southwest flight 4384 to Philadelphia returned to the gate before takeoff after a pilot from another Southwest aircraft reported seeing "potential signs of a mechanical issue," the Southwest statement said.

Smoke was seen coming out of the right engine of the plane, ABC7 in Chicago reported. The captain told passengers that people reported seeing flames, ABC7 said, citing a passenger.

Southwest Flight 3299 bound for Boston aborted takeoff on Wednesday after signs of a "performance issue" with one of the engines, Southwest said.

Southwest said 143 customers evacuated by air stairs and boarded buses to return to the terminal. A replacement aircraft took passengers to Boston later on Wednesday, a few hours behind schedule.