American Airlines Flight 383 (2016)


American Airlines Flight 383 was a regularly scheduled passenger flight operating from Chicago O'Hare International Airport to Miami International Airport. On October 28, 2016, the Boeing 767-300ER operating the flight was accelerating for takeoff down Chicago O'Hare's runway 28R when the aircraft's right engine suffered an uncontained failure that led to a severe fire. The crew managed to abort the takeoff and evacuate everyone on board, while responding emergency services extinguished the fire. Twenty-one people were injured, and the aircraft was substantially damaged and written off.
The right engine suffered a sudden rupture of the stage 2 disk operating at takeoff power. The disk separated into two pieces, the smaller of which pierced the wing's fuel tank and then flew, falling through the roof of a United Parcel Service facility and coming to rest on the building's floor. No UPS employees occupying the building were injured.

Aircraft and crew

The aircraft, a Boeing 767-323 powered by two General Electric CF6-80C2B6 engines, registration number N345AN, was delivered to American in 2003. The right side of the fuselage suffered considerable fire damage. The right wing collapsed about midway along its length. American subsequently declared the aircraft a hull loss. The accidents marks the 17th hull loss of a Boeing 767.
The captain was 61-year-old Anthony Paul Kochenash. He had been flying with American Airlines since May 2001 and previously flown with TWA from January 1986 to April 2001. Kochenash also served with U.S. Navy from May 1976 to December 1985 as a veteran of The Iran–Iraq War. He had 17,400 flight hours, including 4,000 hours on the Boeing 767. The first officer was 57-year-old David Travis Ditzel. Like the captain, he had also been working for American Airlines since May 2001 and previously flown with TWA from December 1995 to April 2001. Ditzel also served with U.S. Navy from May 1980 to December 1995 as an veteran of The Iran–Iraq War, The Gulf War, and The Bosnian War. He had 22,000 flight hours, with 1,600 of them on the Boeing 767.

Accident

At 14:30 central daylight time, Flight 383 was cleared for takeoff on runway 28R. The aircraft commenced its takeoff roll one minute later with the captain as the pilot flying and the first officer as the pilot monitoring. At 14:31:32, the first officer called out "eighty knots," however, 11 seconds after this callout was made, the cockpit voice recorder recorded a loud noise. The aircraft began to veer right and the captain rejected the takeoff.
The first officer radioed to the control tower, "American three eighty three heavy stopping on the runway." The controller had already noticed the engine failure and responded "roger roger. Fire," advising the crew of the situation. The first officer asked the tower controller, "do you see any smoke or fire?" The controller said "yeah fire off the right wing." The first officer ordered the fire trucks to be sent to the aircraft. The captain called for the engine fire checklist, the right engine was shut off, and its fire extinguisher was activated. The captain then called for the evacuation checklist and sounded the evacuation alarm. The first emergency exit was opened 8 to 12 seconds after the aircraft stopped. The pilots then evacuated.

Investigation and recommendations

In July 2017, GE Aviation issued a Service Bulletin recommending that airlines perform regular inspections of first- and second-stage disks of all CF6 engines built prior to 2000.
On January 30, 2018, the National Transportation Safety Board issued its final report on the incident involving American 383. It traced the origin of the failure in disk 2 to a "discrete dirty white spot" that in the Board's judgement would have been undetectable, at manufacture or subsequent inspection, with the inspection techniques available. The NTSB made several safety recommendations as a result, not only with regards to the engine and aircraft but also to issues raised by the evacuation.

Engine inspections

Although the CF6 had been the subject of multiple Federal Aviation Administration airworthiness directives, they had not focused on the larger, relatively slower Stage 1 disks at the front of the engine, made with a nickel alloy. Although the FAA had signaled its intent to issue an order for ultrasonic inspections of CF6-80s in September 2017, the NTSB called for such inspections to be extended to all large commercial aircraft engine models in service. On August 30, 2018 the FAA issued an airworthiness directive that required airlines to perform ongoing ultrasonic inspections for cracks in stage 1 and stage 2 disks on engines like those involved in Flight 383. The NTSB also called for increased design precautions, based on multiple uncontained disk ruptures, to be continually integrated into all commercial aircraft design, especially of the wings and fuel tanks; the FAA has not yet responded to that recommendation.

Procedures

The Board recommended separate engine fire checklists for ground vs. in-flight operation; the checklist used did not so differentiate, and so did not include a separate step where, if the plane was on the ground, the other engine should be stopped to allow evacuation. As a result, a passenger evacuating using the left overwing exit was the only person seriously injured when they were knocked to the ground by exhaust from the still-operating engine. In addition, the checklist provided to the pilots called for discharge of only one of the two fire extinguisher bottles in the affected engine, followed by a wait of 30 seconds to judge its effectiveness; however, other checklists specific to ground operations call for immediate use of both bottles in order to create a safer environment for evacuation of the aircraft.
The Board also faulted communication efforts among the crew, including the inability of flight attendants to successfully operate the interphone and the failure of the flight crew to keep attendants informed of their intention to evacuate. The Board also called for research into countermeasures against passengers evacuating with carry-on luggage despite being specifically instructed not to do so by crew.