YAW STRING FOLLIES

It’s been called the original heads-up display…

Oh you wanna talk retro? The yaw string was in fact history’s very first flight instrument. It performed so well with the Wright brothers’ glider, they installed one on their motorized version as well. A prototype designed with such brilliance, it’s still used all around the world in its original form! Well, except for maybe the tape.

Cool, so where do we plug it in? Answer: your brain. This humble little snippet of thread is absurdly efficient, but like any device, using it without your brain can be more trouble than it’s worth.

All flight instruments have a way of – pun alert – slipping between brain and mind, confusing what you see and what you think. A yaw string can do that too, if you let it. Pilots in glass cockpits don’t fix on any one of those cryptic symbols sliding around their screen, they maintain a suite of mental images, what each detail means individually, and as part of a whole. By comparison, we have it easy. Our little string is the square root of all that, one simple figure suggesting a range of reasoned responses from which to choose. Square roots are small yet potent, and bonus, your yaw string is still the only instrument that never lies!

Take but degree away, untune that string,
And Hark! what discord follows.

Shakespeare

Our problem is, humans instinctively read yaw strings backwards at first… Sounds dumb, but it’s nearly universal, and here’s a theory for why. We’re all used to reading meters of various kinds, with dials that rotate like hands of a clock. Nobody tells time by looking where the hands come together, right? From infancy, untrained eyes follow the lively part of anything that moves. Asking first timers to watch the lazy, unmoving end of a two-inch string is like telling a baby to not drool. Good luck.

So exactly how how does one use this string?

For those transitioning from power, we invoke, “step on the ball,” in our game, “step on the string.” But if that’s all we say, they’re guaranteed to step on the wrong end and get positively negative results. Next, they ask, “You mean if it’s pointing this way…” I’ve bitten holes in my tongue not screaming WHICH END? At that juncture, victims’ minds are disengaged from cerebral function, beyond the ordinary reality in which every string points two directions.

Another common bewilderment disputes which direction is forward, strange as that sounds. When first timers are settling in and want to adjust their rudder pedals, about half say “forward” to pull them closer, the other half say “back” to push them further away! This same cognitive reversal occurs with the string believe it or not. It’s why I always say, “Step where the string is taped to the canopy.” Fail to mention that tape, and invariably their mind tells them the only end is the one closest to their eyes, twitching in the wind.

My brain says look where the string’s going — and isn’t that the point? As it turns out, pedals are located ahead of the string, and the stick is aft of it. I follow the string’s far end with my (forward) feet, and follow its rear end with my (near) hand. Evidently that’s just too simple for some folks to comprehend. Millions have brains that apparently work some reciprocal way, with a vocabulary of mnemonic incantations forever beyond my grasp, but if it werx for them, that’s what counts.

Slogging through this conceptual fog one time, every verbal contortion left my student even more baffled, so I tried the last thing I could think of. I held our model with its tail pointed toward him so he could view it realistically, with the string off to one side indicating relative wind. “Realize that the string is ALWAYS straight,” I said, “Your job is to align yourself with it, one way or another.”

The student’s eyes brightened and he whispered, “Lightbulb!” Taking the model from me, he kept the string where it was, banking toward it and back, and then yawed into alignment by scooting his tail under it. Big grins all around.

Moderation is the silken string
running through the pearl chain of all virtues.

Joseph Hall, Bishop of Norwich

No doubt you’ve heard some wit advocate making the string cooperate by taping both ends — and maybe even repeated the quip yourself? Yeah me too, but here’s one that really did happen: a student was lamenting how the doggone thing just wouldn’t stay straight no matter what he did, as if there were something wrong with the string… So I said, “Maybe we taped the wrong end.” He was happy to agree, for a couple seconds. Then when his brain caught up with his mind, he blushed so loud the back of his neck lit up.

However folks visualize it, by the time they reach an understanding with their string, some are hypnotized and stop thinking about anything else. For others it’s so cheap and easy, and endures the worst neglect with such unobtrusive aplomb, they forget to even look, passively renouncing the string’s inexhaustible service. The only thing worse than being enslaved by your yaw string is ignoring it. Smart money splits the middle, like the oracular string itself. Look through it to where you’re headed and integrate the data subliminally. No need to focus on the string itself, go do your thing.  Just keep ordinary reality in mind as you do.

Also, no rule says your response must be only pedal or only stick. Generally, you’re either coordinating a turn or straightening out a glide, depending on the situation, and often the best input is a wee touch of both…

If it were any simpler I probably couldn’t fathom it either.