In this National Transportation Safety Board handout, NTSB investigators examine damage to the CFM International 56-7B turbofan engine belonging Southwest Airlines Flight 1380 that separated during flight Tuesday in Philadelphia. Investigators can’t explain with certainty why the left engine in the Boeing 737 malfunctioned but are directing their attention to metal fatigue on fan blades. One woman died during the incident. (Photo by Keith Holloway/National Transportation Safety Board via Getty Images)

Delta adding more inspections of its Boeing 737 engines

In the wake of the Southwest Airlines engine failure that left one woman dead, Delta Air Lines said it is adding more inspections of those engines in its fleet.

Atlanta-based Delta’s entire Boeing 737 fleet has the same type of engines that were in the Southwest plane that blew an engine Tuesday.

The CFM56-7B engine that blew on the Southwest flight showed evidence of “metal fatigue,” according to the National Transportation Safety Board. That engine model is on all of Southwest’s 737-700s and 737-800s, which make up the vast majority of its fleet.

Dallas-based Southwest, the second-largest carrier at Hartsfield-Jackson, said Tuesday evening it was accelerating its ultrasonic inspections of fan blades on its CFM56 engines. It said it expects the inspections to be complete over the next 30 days.

Delta said it is also adding ultrasonic inspections of the same engines on its fleet of about 185 Boeing 737s.

“Delta has completed the inspections specified by the manufacturer and has launched additional inspections beyond those recommendations,” said Delta spokesman Brian Kruse. “We’ll complete inspections in advance of the deadline of any directives [to be] issued by the FAA.”

Separately, a Delta flight on an Airbus A330 returned to Hartsfield-Jackson after takeoff Wednesday evening due to a smoking engine. Aircraft rescue and fire fighting units hosed down the plane’s engine while passengers remained on board, then the aircraft was towed to a gate where passengers disembarked. An airport spokesman said there are no reports of injuries.