Southwest Airlines Flight 1380 was a Boeing 737-700 that experienced a contained engine failure in the left CFM56-7B engine after departing from New York–LaGuardia Airport en route to Dallas Love Field on April 17, 2018. The engine cowl was broken in the failure and cowl fragments damaged the fuselage, causing explosive depressurization of the aircraft after damaging a cabin window. Other fragments caused damage to the wing. The crew carried out an emergency descent and diverted to Philadelphia International Airport. One passenger was partially ejected from the aircraft and sustained fatal injuries, while eight other passengers sustained minor injuries. The aircraft was substantially damaged.
This accident was very similar to an accident suffered 20 months earlier by Southwest Airlines Flight 3472 flying the same aircraft type with the same engine type. After that earlier accident, the engine manufacturer, CFM, issued a service directive calling for ultrasonic inspections of the turbine fan blades with certain serial numbers, service cycles or service time. Southwest did not perform the inspection on the engine involved in this failure because it was not within the parameters specified by the directive.
Background
Flight 1380 was a regularly scheduled passenger flight from New York LaGuardia Airport to Dallas Love Field. The aircraft was a Boeing 737-7H4 with the registration N772SW, in service with Southwest Airlines since its manufacture in 2000. It was powered by two CFM56-7B engines.
Tammie Jo Shults, aged 56, a former United States Navy fighter pilot, was the captain of the flight. Darren Lee Ellisor, aged 44, a former United States Air Force (1997–2007) pilot with experience in the Boeing E-3 Sentry and a veteran in the Iraq War, was the first officer. Captain Shults had been with Southwest Airlines since 1994 and had logged a total of 11,715 flight hours, including 10,513 hours on the Boeing 737. First Officer Ellisor had been with the airline since 2008 and had 9,508 flight hours, with 6,927 hours on the Boeing 737. Five crew members and 144 passengers were on board.
Accident
At 11:03 am Eastern Daylight Time, the aircraft was flying at and climbing when the left engine failed. As a result, most of the engine inlet and parts of the cowling broke off. Fragments from the inlet and cowling struck the wing and fuselage and broke a window at row 14 in the passenger compartment, which caused rapid decompression of the aircraft. The flight crew carried out an emergency descent of the aircraft and diverted it to Philadelphia International Airport (PHL).
The flight crew stated that the departure and climb from LaGuardia were normal, with no indications of any problems; the first officer was flying and the captain was monitoring. They reported that the aircraft yawed and set off several cockpit emergency alarms; a "gray puff of smoke" appeared and the aircraft's cabin suddenly lost air pressure. The flight crew donned their emergency oxygen masks and the first officer began the emergency descent. The flight data recorder (FDR) showed that the left engine's performance parameters all dropped simultaneously, vibration became severe and within five seconds the cabin altitude alert activated. The FDR also showed that the aircraft rolled left by about 40° before the flight crew was able to counter the roll. The flight crew reported that the aircraft was very difficult to control throughout the remainder of the flight because of the extensive damage. The captain took over flying the plane and the first officer carried out the emergency checklist. The captain asked the air traffic controller for a course diversion. She initially requested a course to the nearest airport, but then decided that the airport in Philadelphia was best equipped for this aircraft's emergency. The controller quickly provided vectors to PHL. The flight crew reported initial communications difficulties because of the loud noises, distraction and wearing oxygen masks, but as the aircraft descended, communications improved. The captain initially planned on a long final approach to make sure the crew completed all the emergency checklists. Upon learning of the passengers' injuries, however, she decided to speed the approach and expedite landing.