The National Transportation Safety Board is issuing seven safety recommendations based on their investigation into an April 2018 Southwest Airlines flight where a 43-year-old woman was killed when an engine failed.
Jennifer Riordan, a bank executive, wife and mother of two, was killed when she was partially sucked out of a window of Southwest Flight 1380 after the left engine exploded and a piece of shrapnel from the fan blade tore a hole in the airplane's fuselage.
According to the NTSB's summary of the engine failure, Flight 1380 from New York LaGuardia to Dallas-Fort Worth was climbing to 32,000 feet when the engine suffered a catastrophic failure.
"Portions of the left engine inlet and fan cowl separated from the airplane, and fragments from the inlet and fan cowl struck the left wing, the left-side fuselage, and the left horizontal stabilizer. One fan cowl fragment impacted the left-side fuselage near a cabin window, and the window departed the airplane, which resulted in a rapid depressurization," the NTSB said.
Riordan, who was sitting next to the window that was blown off the aircraft, was killed in the incident and eight others suffered minor injuries.
The Southwest pilot at the helm of Flight 1380, Capt. Tammie Jo Shults, has been widely commended for dirverting to Philadelphia and safely landing the plane despite the damage it had sustained.
Shults noted in her recently published book 'Nerves of Steel' that the shock from the blown engine was so violent she thought there had been a midair collision, according to a report in The Dallas Morning News.
"We couldn't see, we couldn't breathe, and a piercing pain stabbed our ears, all while the aircraft snapped into a rapid roll and skidded hard to the left as the nose of the aircraft pitched over, initiating a dive toward the ground," Shults recounted in 'Nerves of Steel,' according to the DMN report.
Findings from the NTSB's official investigation into the event, the first deadly incident involving a Southwest flight, were published Tuesday.
"This accident demonstrates that a fan blade can fail and release differently than that observed during engine certification testing and accounted for in airframe structural analyses," said NTSB Chairman Robert Sumwalt in a statement. "It is important to go beyond routine examination of fan blades; the structural integrity of the engine nacelle components for various airframe and engine combinations needs to be ensured."
The NTSB's recommendations are below.
To the Federal Aviation Administration
- Require Boeing to determine the critical fan blade impact location(s) on the CFM56-7B engine fan case and redesign the fan cowl structure on all Boeing 737 next-generationseries airplanes to ensure the structural integrity of the fan cowl after a fan-blade-out event.
- Once the actions requested in Safety Recommendation  are completed, require Boeing to install the redesigned fan cowl structure on new-production 737 next-generation-series airplanes.
- Once the actions requested in Safety Recommendation  are completed, require operators of Boeing 737 next-generation-series airplanes to retrofit their airplanes with the redesigned fan cowl structure.
- Expand the Title 14 Code of Federal Regulations Part 25 and 33 certification requirements to mandate that airplane and engine manufacturers work collaboratively to (1) analyze all critical fan blade impact locations for all engine operating conditions, the resulting fan blade fragmentation, and the effects of the fan-blade-out-generated loads on the nacelle structure and (2) develop a method to ensure that the analysis findings are fully accounted for in the design of the nacelle structure and its components.
- Develop and issue guidance on ways that air carriers can mitigate hazards to passengers affected by an in-flight loss of seating capacity.
To Southwest Airlines
- Include the lessons learned from the accident involving Southwest Airlines flight 1380 in initial and recurrent flight attendant training, emphasizing the importance of being secured in a jumpseat during emergency landings.
To the European Aviation Safety Agency
- Expand your certification requirements for transport-category airplanes and aircraft engines to mandate that airplane and engine manufacturers work collaboratively to (1) analyze all critical fan blade impact locations for all engine operating conditions, the resulting fan blade fragmentation, and the effects of the fan-blade-out generated loads on the nacelle structure and (2) develop a method to ensure that the analysis findings are fully accounted for in the design of the nacelle structure and its components.
Two passengers on board the flight, including Andrew Needum, a firefighter from Celina, were also lauded as heroes for their effort to pull Riordan back into the airplane during the violent ordeal.
The NTSB's synopsis can be read here. The final report is expected to be available in a few weeks.