MAN AND MACHINE
The Unsung Hero Left Out of ‘Sully’
Clint Eastwood’s movie misses this other player in the drama, the airplane—and makes villains of some really good guys.
Fear of flying has no easy antidote. It’s no good telling sufferers that flying is so much safer than driving on the expressway to the airport. That’s statistics, not the reality of the human condition. But there is one feel-good story that may be invoked to calm the fever: the moment in January 2009 when 150 airline passengers suddenly found themselves heading not for their destination, Charlotte, North Carolina but the ice-cold Hudson River in New York.
This is, of course, the Miracle on the Hudson. US Airways Flight 1549 had lost power from both engines after the engines ingested a flight of Canadian geese soon after taking off from La Guardia Airport.
Few passengers ever bother to know or even care about the names of the pilots to whom they entrust their lives. In this case none of the passengers (and much of the nation) would ever forget the name of the pilot, Captain Chesley Sullenberger, or just Sully.
Now Sully has rightly been elevated into the pantheon of those American heroes worthy of being played by Tom Hanks. The Clint Eastwood directed movie, Sully, is a surprise box office hit. It seems a good moment, then, to finally give credit to a hero so far unsung in this drama.
To do justice to this hero it is necessary to get into the cockpit of Sully’s Airbus A320 with a more demanding eye than the movie has. It involves understanding what happens when an airplane is in its most perilous physical state, absolutely at the edge of its ability to keep flying. Bear with me. It’s worth the effort.
Sully didn’t do it alone, and he knew that he didn’t. There was another hand flying that Airbus to a heart-stopping splashdown. If you watch the movie carefully you can catch a fleeting glimpse of what I’m talking about.
In the final seconds before the airplane hits the water you’ll see Sully’s left hand (or rather Tom Hanks’s hand playing Sully’s gifted hand) on the sidestick controlling the airplane. He appears to be pulling hard back to keep the nose up.
In fact, Sully’s command was being overridden by the Airbus’s own brain. It reduced the nose-up angle by two-and-a-half degrees. Sully wasn’t pulling back too hard, he wanted all the angle he could get to soften the impact on the water. But he knew that the airplane itself was computing how to preserve control when at the limits of its ability to keep flying, and that it would know how to do that better than he did. This
turned out to be an extraordinary, exquisite moment when a machine and a man, together, got it exactly right.
Had the airplane had conventional controls with a yoke, or wheel, directly in front of the pilots – the classic “joystick” of aviation legend – the end of that flight might have been very different. But the Airbus has that sidestick, looking a lot like an old Atari control stick. And the sidestick is transmitting input from the pilot into the computers where it is governed by a system called envelope protection.
Put simply, the envelope is a kind of three-dimensional box in the sky inside which the airplane remains stable and under control and outside which it must not stray for fear of crashing.
When an airplane is on the margins, as Sully’s was, the greatest danger is an aerodynamic stall. If the airplane is flying too slowly and the nose is up, its wings will suddenly lose all lift – and the pilot loses all control over what it then does.
Sully’s own brain was processing his situation as acutely as the computer was, with the kind of instincts and acuity that only a pilot at the top of his game has. In the 300 or so seconds since the bird strike took out both of his engines Sully’s brain had made multiple calls and all of them were right (we’ll get to the two most important later).
The intervention of the computer to lower the nose meant that Sully had one less pressure on him when his hand on the sidestick was taking another action that made all the difference between surviving and disaster.
“He kept his wings almost perfectly level at touchdown” Robert Benzon, who led the National Transportation Safety Board’s investigation into the accident, told The Daily Beast. “A dipped wing would have turned the A320 into a water-borne Frisbee.”
Boeing has adopted most of the same cockpit automation as Airbus, but signally stopped short of abandoning the yoke and allowing the computers to override the pilot. In a Boeing cockpit there is no envelope protection. Instead the yoke begins shaking to warn the pilot if the airplane approaches stall. It remains central to Boeing philosophy about the relationship of pilot and machine that the pilot retains authority.
But, in case you’re wondering, neither Boeing nor Airbus will argue that their contrasting philosophies on the degree of latitude allowed a pilot in extremis is safer than the other.
It’s just not that simple.
In many ways cockpit automation has made flying much safer, but there is a problem. Most of the new generation of airline pilots have never had to revert to their own instincts and reflexes in a crisis in the way that Sully did. A spate of recent crashes has involved pilots getting into fatal aerodynamic stalls and not knowing how to get out of them. As a result, new enhanced flight simulators are coming into use specifically to train pilots for that event.
Those crashes have happened in both Airbus and Boeing airplanes. In an Airbus one factor has been what happens if the primary computers fail – for example, if there is a loss of electrical power. In that case the envelope protection system is also lost and pilots have to fly the airplane manually. It was assumed that they would be able to do this successfully when under stress and when facing other failures. That assumption has sometimes been misplaced. The new simulators will put all airline pilots through that stress and show them how to handle it. (Alaska Airlines pilots will be the first to use it.)
Sully’s own view of the Airbus system is pertinent. In the final one of three interviews that the NTSB conducted with him he was asked to compare the Boeing and Airbus systems. He said that the Airbus protection systems “went far beyond” the warnings of a “conventional” (i.e., Boeing) airplane.”
People who have seen the movie will no doubt be surprised to hear that interviews between Sully and his copilot Jeffrey Skiles and the NTSB were serious and civilized and devoted to learning the lessons of the experience – hopefully one that no pilot would in future be faced with. The NTSB wanted to make sure that if they were, they would be better prepared to handle it.
In the movie the NTSB investigators are cast as the villains – they convene what seems like a kangaroo court and, from the start, interrogate the pilots in a way that implies that by choosing to land on the Hudson Sully made the wrong call, that he could have made it back to where the flight began, La Guardia, or, alternatively, to nearby Teterboro in New Jersey. The screenwriter, Todd Komarnicki, told the BBC that the NTSB “spent nine months trying to pin this on him…they didn’t like that he was a hero.”
This is no small matter. We are not talking about arcane technical details best excised from film scripts. Reputations are involved.
The NTSB is a relatively small government agency with an annual budget of $105 million – it has a staff of 423 people of whom 130 are aviation safety investigators.
The NTSB’s chief of media relations, Christopher O’Neil, told the Daily Beast: “Using the NTSB’s investigation of the accident as the movie’s antagonist is unfortunate and belies the purpose of the investigation and the benefits of our comprehensive investigative process. Thirty-five safety recommendations were issued as a result of our investigation of the ditching of Flight 1549.
“The NTSB was not asked to contribute in the production of Sully and as such we were not afforded an opportunity to ensure our actions and words were portrayed with accurate context or reflected our perspective.”
When Benzon arrived in New York on the evening of January 15 to take charge of the investigation he was at the peak of a distinguished career. He was veteran of many investigations and, four years earlier, had been accorded the Chairman’s Award, the highest honor given to NTSB staff. One of the first things he did was to ask for a tally of survivors. He was incredulous that everyone had survived. After counts by the New York police and the New York fire department he asked for a third from the New York City Office of Emergency Management, all confirming that there were no casualties.
Benzon recognized that this was a unique situation in his experience. The pilots had a story to tell that would throw an invaluable light on the interaction of them and the Airbus automated cockpit. There was a captain with unusually deep experience combining old-school seat-of-the-pants skills with an understanding of a computerized flight management system.
Two days after the crash, Sully and Skiles had their first interviews with the investigating team. The movie shows them together at a table opposite the team but, in fact, they were interviewed individually and consecutively, normal procedure, Sully for two hours and 45 minutes and Skiles for two hours and 18 minutes. More than two months later, on March 27, they were both interviewed again, this time on the phone, Sully for an hour and 10 minutes and Skiles for an hour.
On June 15 – after he had appeared with Skiles at a public hearing – Sully was interviewed again, on the phone, for 31 minutes.
Transcripts of the interviews show that at no time was there anything resembling an inquisition of the pilots. Moreover, in Sully’s final interview in June the investigators were respectfully listening to Sully’s ideas for improving pilots’ understanding of the Airbus systems.
A key part of the movie’s dramatic tension is based on real-time reconstructions of the flight made on simulators at the Airbus headquarters in Toulouse, France. These are set-up by the script as the NTSB’s “gotcha” moment. The simulator pilots appear to make successful landings at both LaGuardia and Teterboro – until 35 seconds is deducted from the time available to make the diversion, the actual time that elapsed between the bird strike and Sully’s assessment of his options. Then, with that adjustment, in the movie’s triumphal moment, all the simulated attempts to make it to a runway end in crashes.
In fact, the purpose of the simulations was not to try to demonstrate that Sully had made the wrong call but to see what resources the airplane had to remain flying without thrust and for how long. Fifteen runs were made in the simulator. Even before the 35-second delay was introduced it became obvious after several runs that diverting to either of the two airports was far too dangerous and further attempts were abandoned.
In reality the investigators understood from the start that Sully had made two calls that made the difference between a miracle and a disaster.
The first was how quickly he assessed his options, ruled out turning back to an airport and decided to fly over the George Washington Bridge and down into the Hudson, putting himself clear of the skyscrapers of Manhattan on his left and the cities of New Jersey on his right.
The second decision was just as critical and it was not on the checklist for an emergency like this one. Based just on instinct, Sully switched on the auxiliary power unit, a small turbine engine in the rear of the airplane that normally supplies power when the airplane is at the gate and the engines are shut down. Without the power generated by that unit there would not have been enough electrical power for the computers to provide the flight envelope protection. Sully would have lost the hidden hand that helped him save the airplane.
In Benzon’s words, “the airplane had the pilot’s back.”
The last 15 minutes of the movie are compelling. Eastwood gives a master class in the choreography of a multiple viewpoint spectacle. The digital rendering of the airplane, the crash and the rescue is chillingly visceral. Hanks, as usual, wholly becomes the part.
It’s a pity that the filmmakers felt that in order to pump up the drama they had to traduce people who are among the most dedicated public servants we have – the reason why flying is as safe as it is has a lot to do with the consummate forensic skills of NTSB investigators. Over the years they have steadily pinpointed and eliminated failures, both human and mechanical, and saved many lives.
Benzon fears that the movie will make that job harder.
“I do not know why the writer and director chose to twist the role of the NTSB into such an inaccurate depiction. Their treatment of the NTSB went very far beyond cinematic license into simple mean-spirited dishonesty. The movie may actually be detrimental to aviation safety. Pilots involved in accidents will now expect harsh, unfair treatment by investigators. They and others who see the movie will now believe that the NTSB enters into any investigation with preconceived notions, and that we are intent on destroying reputations. Simply untrue. The NTSB is the best friend an airline passenger never gets to meet.”