Crew Successfully Handled Altitude, Passengers After Engine Breakup

The Air France Flight 66 (AF066) accident in 2017 not only bears metallurgy lessons for OEMs but also serves as an example of airmanship. The flight crew adapted existing procedures to a serious event that had not been addressed in any manual or simulator session. They also worked effectively with the cabin crew to prevent passengers from becoming a hazard during the 17 hr. they spent in the cabin after landing.

The Airbus A380 suffered an inflight breakup of one of its four Engine Alliance GP7200 turbofans when climbing over Greenland on Sept. 30, 2017.

• Pilots faced undocumented engine event
• Captain had previous experience with unruly passengers

Flight AF066 had taken off from Paris to Los Angeles with 521 people on board, including 497 passengers. The fan rotor on engine No. 4 (outboard on the right wing) separated during the climb from Flight Level 370. Debris harmed no one onboard and caused little damage to the surrounding airframe structure. The crew diverted to Goose Bay, Newfoundland, without further harm.

French accident investigation bureau BEA released its final report last September. Investigators determined the root cause of the accident—characterized as such because they deemed it considerably more serious than most engine failures—was dwell fatigue of a metal that had been regarded as immune to such deterioration (AW&ST Oct. 12-25, 2020, p. 24).

Aviation Week recently talked with two crewmembers who have since retired: the captain and the chief purser.

Immediately after the engine breakup, the main difficulty for the pilots was finding the right flight level, the report emphasizes. The laws of aerodynamics imply that if an engine fails, the crew must lower the cruise altitude. That procedure is well-known; however, it was devised for a straightforward event. Such altitude calculations are based on a windmilling engine and do not factor in the increased drag that a jammed or heavily damaged engine creates.

When the pilots detected the failure, they reduced speed as indicated in manuals. The primary flight displays showed a new target speed. They entered a descent to the driftdown flight level—the altitude at which the aircraft stabilizes—computed by the flight management system.

“The crew was surprised not to be able to maintain that level at constant speed,” BEA investigators say.

“Airbus says these are maximum values, but this is not the way you see them until you have to use them,” Capt. Christian Villard notes. “The situation was far from what we learn in the simulator. It is easy to say afterward that the cause of our difficulties was additional drag from the crippled engine, but when we were at the controls, we could see plenty of other possibilities.”

The final driftdown level was impossible to evaluate, so the crew got creative. They entered a descent in successive stages until they found an altitude the aircraft could sustain. They stabilized it at FL 270, 7,000 ft. below the expected altitude.

That phase lasted 26 min. During that time, the crew also had to determine whether the right wing was burning—it was not—and estimate a new stall speed because of the damage.

Choosing a diversion airport was challenging, but the crew easily reached an agreement. Rather than opting for a slightly closer option, the runway at Goose Bay (2.5 hr. away) could accommodate the aircraft even without functioning slats and flaps. “We could see that the right-wing leading edge was damaged, and in [cases when] aircraft systems detect uneven lift between the wings, they prevent high-lift devices from deploying,” Villard explains.

Air France’s operations control center also favored Goose Bay, which would likely offer more backup aircraft options for the passengers. What happened next showed that making the passengers part of the equation was particularly relevant.

Should the crew have dumped fuel? That would have helped reduce the aircraft’s weight below the maximum landing weight, as required in the flight manual, Villard says. The fuel system, however, automatically transfers fuel into nondrainable “feed tanks” when preparing for the descent and approach phase. The crew could have dumped fuel earlier, but the aircraft was flying over an inhospitable area and at a time when the choice of the diversion airport could still change. Moreover, if shrapnel had created a leak, they risked running out of fuel.

Regardless, “landing over weight is not too complicated,” Villard explains. “We train for that in the simulator.” The damage on the leading edge, however, prompted him to increase landing speed by 10 kt. “Calculations showed it was compatible with runway length,” he noties.

Another concern was preserving the cockpit voice and sound recording. The available duration on the cockpit voice recorder (CVR) is approximately 2 hr. Beyond that, the CVR overwrites the previous data.

The crew quickly understood that more than 2 hr. of flight time would likely elapse after the fan burst. The landing at Goose Bay Airport actually occurred about 2 hr. later, but taxiing downwind on the runway took some time. The crew requested an airport vehicle to inspect the runway and remove any debris that had fallen during landing; otherwise the aircraft could have run into damaging shrapnel.

On an Airbus, the CVR stops 5 min. after the last engine shutdown. In the case of AF066, the recording stopped 2 hr. 37 min. after the engine failure. The event is therefore absent from the recording.

The captain had anticipated the need to preserve the CVR data and asked the relief pilot (the third flight crewmember) to prepare to disconnect a fuse and cut the CVR’s power shortly after landing. But the pilot was unable to locate the fuse because it was not where onboard documentation had indicated.

Overall, investigators found that “all the decisions the captain made were first discussed and agreed” upon and that his leadership created a climate of trust that was “conducive to the performance of the safety tasks and the reassurance of the passengers.”

The decision-making method, known as FOR-DEC (facts, options, risks and benefits, decide, execute, check), “proved an effective tool,” the BEA says.

When referring to crew action, the report focuses on what happened in the cockpit. But the entire crew spared no effort when dealing with the passengers while they were waiting inside the aircraft for backup aircraft that would take them to their final destinations. And the lessons drawn from that phase fall under the safety category.

“I hit the park brake and said, ‘Now passengers are the problem, and it will be no simple matter,” Villard recalls. Two years earlier he had faced a serious situation onboard in comparable circumstances. At the end of a transatlantic flight, another Air France captain landed in Manchester, England, because the crew’s duty time had elapsed due to predeparture complications. Villard was one of the pilots Air France sent as a replacement. Further annoyances caused more delays for the A380 in Manchester, but the passengers were stuck inside.

“The relationship with the passengers turned sour,” Villard says. “Some were commanding me to let them disembark, and a riot was looming. I had to call the police and take one cop on board.” The flight was canceled after a passenger fainted.

In theory, Goose Bay Airport was responsible for taking care of the passengers once they were on the ground. But neither the airport nor the neighboring hotels had capacity for 497 people, nor could passengers remain in a hangar with safety blankets. So Villard elected to have them wait on board until backup aircraft landed. To avoid a repeat of his predicament in Manchester, Villard made passenger-morale management a priority. Chief Purser Sylvie Schurck took center stage.

Cooperation between the pilots and the 21-strong cabin crew intensified after the event. A flight attendant immediately lent her iPad to a passenger and asked him to take a photo of the engine. She brought the picture to the flight crew, thus helping with situational awareness.

Benevolence, delegation and authority were three key words, Schurck emphasizes. “In the crew, we were consistently kind to each other,” she recalls. “I made a point to delegate responsibilities because I could not make every decision, but I asked my team to report after acting. And I talked firmly to those passengers who were getting angry.”

On the ground, Villard received help from Air France’s A380 chief pilot in Paris. One flight attendant had a travel companion among the passengers, but they risked being separated because passengers and crew were supposed to part ways upon disembarking. “The chief pilot said, ‘The companion stays with the crew,’ and it had a favorable effect on the entire cabin crew,” Villard says. “It strengthened cohesion.”

“I felt the captain listened to us and took our requests into account,” Schurck stresses.

Accommodating passenger needs was a successful way to keep them calm. “I had an idea—what about asking the airport to provide us with a van to take smokers to a convenient place?” Villard says. It worked and flight attendants organized groups of 15-20, including smokers as well as children, who could thus access space to run around in.

The improvised but effective shuttle was also a source of frustration for some ill-behaved passengers. “I told them, ‘Be patient. If you do not calm down, we are going to stop this, and everyone will stay in the aircraft,” Schurck says. The crew had to deal with a total of 11 unruly passengers.

The atmosphere remained relaxed overall; most passengers appreciated that the crew was so attentive. One passenger was able to walk his dog, which otherwise would have spent a long time in the dedicated hold. Another one requested a sedative. The crew did not have one, but a Tic Tac had the intended soothing effect.

“You should not leave a customer request unanswered, and you should express empathy,” Schurck says. “We spent 17 hr. on the ground with the passengers.”

Crewmembers took turns for 1.5-hr. breaks, always leaving two-thirds of the team on duty. “Eleven passengers were agitated,” Schurck recalls. “I did not want more than one-third of us to leave the cabin for the crew rest compartment. We did not sleep, but isolating from passengers helped.”

The aforementioned 11 passengers sued Air France on “endangerment of life.” This notwithstanding, in an era when widespread, strong reaction on social media is commonplace, no such backlash occurred—a testament to the crew’s appropriate actions.