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Let it rideLet it ride

Overcontrolling is annoying and can break airplanes

Have you driven with the twitchy type? You know the drivers who feel like they have to be constantly moving something—the steering wheel, gas pedal, and brakes (often simultaneously)—to effectively drive a car. Now, imagine a pilot flying like that. Not only is it uncomfortable, it can be downright dangerous, as these overcontrollers have actually broken airplanes.
AOPA Turbine Pilot
Illustration by Sarah Jones

Overcontrollers can be easily found on YouTube, often in airline pilots documenting their own landings in strong and/or gusty crosswinds with an in-cockpit camera. You can see the pilot making constant huge corrections on the yoke, power levers, and trim. Sure, at slower speeds jets require larger control yoke movements to make things happen when compared to light airplanes, but the telltale sign of the overcontroller is the constant correction of his corrections. Overcontrollers often correct too much and therefore must double their efforts to keep the airplane on the desired path. It looks exhausting, and it is. But overcontrollers feel that all that heroic effort is part of the job. It’s not. It’s hard on the airplane, uncomfortable for passengers, and alarms your co-pilot. It makes one wonder, Who’s really in control here?

During climbout on a typical flight, overcontrollers don’t seem to notice that after turning on the autopilot, the spastic movements on the control wheel stop. You don’t see an autopilot performing the same monkey motion. It employs smooth, methodical corrections—just enough to get the job done—to keep the airplane on the proper path. Likewise, if the approach is flown in strong, gusty crosswinds with the autopilot on, it dutifully performs the same way. And when the overcontrolling pilot disconnects it, he fails to notice the now massive and constant gyrations he’s using on the yoke, rudder, trim, and power levers. Sigh.

Perhaps the best-known case of overcontrolling was the November 12, 2001, crash of American Airlines Flight 587, an Airbus A300 widebody in Belle Harbor, New York. After encountering wake turbulence from the Boeing 747 that departed immediately prior, AA587’s first officer, who was the flying pilot, overreacted to the event—leading to the separation of the vertical stabilizer, rudder and all. The National Transportation Safety Board cited the “first officer’s unnecessary and excessive rudder pedal inputs” as the main factor leading to the breakup. The crash killed 260 people in the airplane and five on the ground, making it the second deadliest airplane accident in U.S. history.

Wake turbulence’s signature trait is uncommanded roll. Naturally, this is countered with aileron. Use of rudder in swept-wing jets to counter wake turbulence is unnecessary in nearly all circumstances and could introduce unrelated controllability issues if used excessively. AA587’s first officer was otherwise considered an “excellent” pilot who was “smooth and accurate” on the controls by his peers. By all indications he was not your typical overcontroller. However, he had a history of overreacting to wake turbulence encounters, revealed during post-accident interviews with pilots he had flown with. He used a combination of large aileron and equally large rudder inputs to right the airplane.

When one captain debriefed him on his actions, the first officer said that the company’s advanced aircraft maneuvering program directed him to react in such a manner. That was a bit of a stretch. The program did mention small, “smoothly applied” rudder application was warranted if aileron inputs were insufficient. More likely, the NTSB argued, the first officer confused roll upset recovery technique with excessive bank recovery maneuvers.

Actions by the first officer placed an unusually high side load on the stabilizer. According to the report, a force of about 200,000 pounds was placed on the stabilizer before it failed. That’s double the 100,000-pound force it was certified to withstand per Airbus’ design.

The accident was an awakening to pilots, because AA587 was flying below its design maneuvering speed (VA) yet was broken by pilot inputs. VA is the speed at which the airplane will stall before exceeding its design limit load factor in turbulent conditions or when the flight controls are suddenly and fully deflected in flight. Most pilots took that to mean that nothing we could do inside the cockpit could damage the airplane when operating below maneuvering speed. AA587 changed all of that.

From the NTSB report: “An inappropriate rudder input can produce a large sideslip angle, which will generate a large rolling moment that requires significant lateral control input to stop the airplane from rolling. The rudder should not normally be used to induce roll through sideslip because the transient sideslip can induce very rapid roll rates with significant time delay. The combination of rapid roll rates and time delay can startle the pilot, which in turn can cause the pilot to overreact in the opposite direction. The overreaction can induce abrupt yawing moments and violent out-of-phase roll rates, which can lead to successive cyclic rudder deflections, known as rudder reversals. Large aggressive control reversals can lead to loads that can exceed structural design limits.”

The takeaway from all of this is to let it ride. Let your airplane ride through the turbulence or bumps with minimal control inputs. Dealing with wind and wake is not some sort of battle that requires Herculean efforts to keep the airplane upright. All certified airplanes are positively stable machines that typically recover from upsets with minimal pilot input. Caught in the throes of wake turbulence? Just hold as much aileron as needed to maintain wings level. If you’re in a jet, use minimal rudder and only if necessary.

Emulate the autopilot and auto-throttle(s), if equipped. During many wake turbulence encounters, I’ve watched the autopilot deal with wake turbulence while guarding the controls in case it kicks off. Often, you’ll see it move the yoke about 10 to 20 degrees off center and hold it right there for as long as necessary. Likewise, autothrottles do what needs to be done with smooth, deliberate precision. After clicking off all of the automation for landing, attempt to mimic the smoothness of the automation.

Critique your handling of the airplane. Ask yourself, “Do I really need to use this much correction? Am I correcting my own corrections? Can I be smoother in my inputs?” I, too, have been guilty of overcontrolling. But the key was recognizing it. One example, in the roundout to flare during a gusty crosswind landing years ago, I jabbed in too much rudder, causing my captain to say “Whoa.” I got it all quickly under control and landed normally. Back at the gate, I apologized about the overcontrolling and explained that I put in too much correction too quickly because I overestimated my sink rate and wasn’t sure I was going to be able to kick out the crab before touchdown. Turned out, I overcontrolled the pitch a little, too, and floated long enough to work everything out for a decent touchdown—albeit longer than I wanted.

My captain said he was startled by the input because, for the balance of our previous three days of flying together, it was unlike me to manhandle the airplane like that. He was happy I debriefed the incident and owned up to it. Naturally, he suggested that I stand at the cockpit door to face our deplaning passengers and account for my twitchy touchdown. Fair enough. I deserved it.

Peter A. Bedell

Pete Bedell is a pilot for a major airline and co-owner of a Cessna 172M and Beechcraft Baron D55.

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