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Pilots on Autopilot
Pensacola, Fla.
THE Northwest Airlines pilots who became so absorbed in their laptop PCs that they flew 150 miles past their destination have added to the concerns of the public, during this busy holiday travel season. This incident should also be a wake-up call to the aviation industry.
Decades of technological enhancements and automation have made flying undeniably much safer but also fostered a subtle disconnect between pilots and the planes they fly. Designed to reduce crew workload and enhance safety, today’s highly automated aircraft can leave pilots so detached from flying that they become almost like passengers on their own flights. That’s apparently what happened on Northwest Flight 188.
Once the busy takeoff and departure was behind them and their aircraft was at cruising level, with the autopilot and the flight management system doing all the flying and navigating, the pilots felt comfortable enough to get to work on a new crew scheduling program. In cruise flight, all they were required to do was monitor the plane’s flightpath, have an awareness of other traffic, monitor systems and respond to radioed air traffic control instructions. Pilots call it being “situationally aware.”
But these pilots’ preoccupation was so deep that situational awareness went out the window and even radio calls were tuned out. The plane was on its own and this crew was along for the ride just like the folks in the back. What got the crew into this pickle was thousands of hours in highly reliable, automated planes that over time made them ever more confident and blunted their need to be involved in the tasks of flying.
In contrast, the early years of jet travel required far more crew involvement and there was always something to do or watch over. When I was a Pan Am Boeing 707 co-pilot in the late ’60s, few cockpit controls and systems were fully automated. Most required periodic attention and resetting to operate properly.
After a series of computations for temperature, altitude and other considerations, engine thrust had to be carefully set for takeoff and reset during climb and cruise. Controlling pressurization and adjusting cabin cooling was a respected art performed by the flight engineer, who also made sure that the wings stayed in balance and fuel from the plane’s seven tanks fed the engines. Flying over land, pilots continually retuned and identified navigation radios, reset courses and adjusted heading for wind drift.
Flying over the ocean still required a knowledge of celestial navigation. Our 707’s had a periscopic sextant on board that could be popped through a small round hatch in the cockpit ceiling for star shots. On Atlantic crossings, pilots used a World War II-era long-range radio navigation system known as Loran to manually plot position. On some long Pacific flights where Loran coverage was too sparse, navigators were the hardest workers, taking star shots, measuring drift and passing heading correction slips to the pilots.
These disciplines required extreme accuracy and skill. And with all the numbers and variables of this demanding work, errors were expected and occurred. That’s why Pan Am required additional verification steps from another pilot to confirm each course change or future position. In short, even when things were going smoothly during level cruise flight, cockpit crews had to be more actively involved to get where they were going.
By the early 1980s, aircraft systems and automation had evolved significantly. Most of the manual chores of staying on the airways or oceanic tracks were eliminated. In many planes, there was no longer a flight engineer sitting sideways behind the pilots, facing a bank of gauges, status lights, toggle switches and levers to operate the plane’s systems. Those functions had been automated, their controls condensed and placed in the pilot’s overhead panel.
By the late ’80s, I was a captain on the A310, a highly automated Airbus jet. I had evolved from the hands-on flier of my earlier years to a systems manager, controlling the plane with a flight management keyboard. During qualification training, pilots quipped that to pass their F.A.A. simulator checkride they had to be able to type 50 words a minute. It was a joke, but not far from the truth. Today it’s the way we fly new airliners, with G.P.S. accurate to within a few feet and computers, known as fly-by-wire systems, sending commands to the engines and all flight control surfaces.
The challenge now is to keep airline crews connected and aware when all this automation relieves them of the details and tasks that kept pilots on their toes in years past. Manufacturers must develop an effective alerting system to complement — or rather mitigate — the effects of advanced automation.
Designing an alert intrusive enough to yank crews back to reality in moments when they’re not responding to conditions won’t be easy and it will have to be right. Today’s cockpits are already filled with annunciator lights, caution lights, and all sorts of indicators and displays, most with their own distinct sounds and decibel levels. Aviation accidents often involve inappropriate or misunderstood alerts, which in some cases were even disconnected before a crash.
But the best safety device is the pilot, who, deep down, regardless of the aircraft, retains a sense of fallibility and vulnerability. No system can ever substitute for that.
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