FAA orders emergency inspection of fan blades after Southwest failure

The Boeing 737 aircraft that Jennifer Riordan was a passenger on had a fault in one of its CFM56-7B engines, and ultrasonic tests on fan blades that have performed 30,000 or more total accumulated flight cycles will be carried out.

Southwest's existing engine maintenance programme "meets or exceeds" all requirements in the new directive, the airline said on Friday.

Authorities say nearly 700 Boeing 737 engines will need to be checked worldwide over the next 20 days.

Southwest has sent a letter of apology, a US$5000 (NZ$6940) cheque and a US$1000 travel voucher to passengers who were on a flight that made an emergency landing in Philadelphia, US, after an engine exploded. Riordan died at a hospital after the plane made an emergency landing in Philadelphia. Fellow passengers pulled the woman back in and attempted to revive her. On Tuesday, debris broke through one of cabin windows, and one passenger died as a result.

A subsequent NTSB investigation found that a fan blade had separated from the engine hub due to metal fatigue that had produced a crack in the fan.

Ultrasonic inspections on fan blades that have been used in more than 30,000 cycles, or in service for about 20 years, will be required in the next 20 days, the agencies said on Friday.

Friday's announcement came shortly after the engine manufacturer, CFM International, issued a service bulletin recommending the CFM56-7B engine be inspected more frequently.

"The public should be anxious (because) a manufacturer sent out a warning, and Southwest and others didn't do it", said Mary Schiavo, a former inspector general of the Transportation Department, FAA's parent agency.

He also said the FAA did not move quickly enough to require inspections after a punctured Southwest 737 was forced to make an emergency landing in 2016 in Florida because of an engine failure caused by metal fatigue. Investigators say a fan blade broke off in flight, triggering a chain of events that shattered a window on the Boeing 737-700.

Southwest had initially pushed back against CFM International's recommendation that inspections be completed within 12 months and had asked for more time a year ago, reported The Associated Press. The European agency had given airlines nine months to check engines, while United States regulators still were considering what to do. A spokeswoman told AP that the airline had already inspected about half of the engine blades identified by the manufacturer's recommendation before this week's accident.

According to the National Transportation Safety Board's official report, several factors were blamed for the crash including a catastrophic fan blade fracture in the number 2 tail-mounted engine. Uncontained engine failures are rare - about three or four a year, according to Sumwalt. "So it's a fairly big deal for this kind of failure to happen".

  • Anthony Vega