One Hand On The Yoke

An airplane's direction and attitude is controlled primarily by a 3D steering wheel called a "yoke" (plus other inputs like the rudder pedals, which don't bear on this story). When my father-in-law first showed me how to fly, I immediately grabbed the yoke with both hands. We bounced around a bit. Then he showed me how much smoother I could fly straight and level with only one hand on the yoke.

An airplane is a much more sensitive control situation than a car. Small changes to the inputs are very noticeable. Something about the need to coordinate the pressure of two hands generates many, many of these small inputs. Counter-intuitive as it feels at the time, 10,000 feet up in a tiny little cigar tube, letting one hand go is the right way to solve the problem.

Now, when you do a manoeuver, you do hold the yoke with both hands. Then you need the power provided by both armsful of muscles. At least you want that power available, and you are willing to pay the price in a little wiggliness, at least for the duration of the turn.

An ExtremeTeam is sensitive to small inputs. Much better to let one hand go and trust the self-organizing culture they have developed. Most of the time.


Another example of this is my rolling suitcase. The wheels are too close together, so it often starts oscillating between the wheels, eventually falling over. I tried grabbing tighter, which started the oscillation sooner and toppled the suitcase sooner. The solution is to pull the dang thing with one finger. Occasionally (but much less often) it still begins to wobble. I slow down until it stops.

--KentBeck


I too have a rolling suitcase with this problem. Very annoying as I usually have a laptop perched on the pullout arm as I am hustling through the airport. The suitcase starts wobbling and immediately dumps the laptop on the floor. My solution is to pack the bag with all of the heavy stuff (usually computer books) at the bottom. I rarely get the dreaded wobble anymore. Ken Riley
Buy yourself a better suitcase. Do you mean "better" as in "better suited to being manipulated by a control freak"?

I believe by better, is meant that you find it less likely to wobble. This is determined not only by how it is packed, but by the distance between the wheels, with the best option being that of having the wheels at the edges. My daughter bought one recently which has wheels on the outside edge. It doesn't wobble, therefore with regard to pullability it is a "better suitcase". It is a matter of making the base of the triangle as wide as possible with the ratio of the base to the length to a centered pulling point as large as possible (and also the center of gravity as centrally low as possible). This is an example of DoTheBestThingThatCanPossiblyWork?, as opposed to the DoTheEasiestThingThatCouldPossiblyWork, DoTheMostComplexThingThatCouldPossiblyWork, DoTheMostComplicatedThingThatCouldPossiblyWork, or even DoTheSimplestThingThatCouldPossiblyWork! Particularly if you take into consideration that you are the "worker". --DonaldNoyes

By DoTheBestThingThatCanPossiblyWork?, do you mean DoTheRightThing ?


I've never flown an airplane, but I have found that the same idea applies to driving a car extremely straight (wide trailer, narrow bridge). Two hands sometimes seem to "fight" each other and generate small pertubations. One hand (and full concentration!) works better. I think this is related to the idea that a person with one watch knows what time it is, while a person with two watches is never sure. -KyleCordes
Getting back to airplanes, it's not really a question of sensitivity: a car's steering wheel is also very sensitive. The reason that you grip a yoke with one hand (preferably just thumb and forefinger) is to avoid pulling the aircraft out of its trimmed angle of attack. When you try to change a plane's angle of attack (say, by pulling back), the yoke will pull against you trying to get back to its trimmed position. With two hands, or even just one clenched fist, you can pull on the yoke without realizing it and (in the worst case) end up in a stall/spin, or (in slightly better case) end up bouncing around with passengers throwing up all over the plane. With just thumb and forefinger, you can feel the yoke pulling back more, so it takes a deliberate effort to pull the plane out of the trim you've set. --David Megginson (sorry, no Wiki link)
Is this LaissezFaire? in a way? --IvanStojic
SteerWithYourEyes, TheSoundOfOneHandClapping?
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