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Josiah

Without a Little Gyro

Updated: Aug 18, 2022


There's been a cure all along, but we the people don't need a cure for these disoriented, COVID-ential times! And before you tune me out, thinking this is a political blog, I'll clarify: I'm talking about the disorienting task of flying a quadcopter without the added benefit of a gyro.

I've been bitten by the bug, charged by the battery, and inspired by the Jonny FPVs of freestyle drone flying. The simulator I've purchased, Velocidrone, has only instilled this desire to persevere in this line of unreasonableness. Unreasonable? Yes. Unreasonable. Who would want to risk flipping a topsy-turvy, $300 drone around the sky for three minutes with a Go-Pro strapped to the top of it? Really? ...Okay, I do.

The hitch of it all is that, like me hopping into an F-14 Tomcat with the intent of going supersonic on my first day of flight-school, instinct differs quite a bit from intuitiveness when it comes to a freestyle drone.

Are you ready for a crash course? (I know, I know, I've used that pun already; I'm referring to the instructional crash course here.)

Power, Pitch, Bank, Yaw

...Power Pitch Bank Yaw... PowerPitchBankYaw... PowerPitBkYa... PowPiBaYa...

Lift—is up. It's always up—err, always perpendicular to the propellers in the up direction. Think "Alfalfa" from The Little Rascals, his notable features were freckles and a glue of black hair that always pointed straight up on the top of his head. If Alfalfa's head swiveled like a quadcopter swivels, his hair was always pointing in the direction of lift. Remember, there are no wings on a freestyle drone. "Okay, that's simple enough." Yeah, that's what I thought too.

Weight—is down. It's always down, unless you've reached low-Earth orbit—err, no, not even then (and if you've reached low Earth orbit, disregard my explanation above on quadcopter lift). Weight due to gravity always pulls you straight down.

Drag—I'm going to ignore drag for now, although it's there, just like wind is there. However, neither drag nor wind significantly impact learning how to hover your freestyle drone in a windless simulator which is the first thing (and probably hardest thing) you'll have to do when starting out (that is outside of explaining to the manager of a high-rise building how and why you crashed your drone into the penthouse balcony).

Pitch—adjusts the lift vector forward and backward. Pitch works directly in conjunction with power, both in airplanes as well as freestyle quadcopters. I make this connection here because the moment you pitch after your first takeoff, you'll need to think about power. Power is a different way of thinking about lift, relating lift more to your gimbal inputs. Yet, it's both pitch and power that make the quadcopter move forward. Moving forward is similar to drifting forward, but when you analyze it, it's completely different. Drift happens due to either momentum from the drone or the wind. "But Josiah, you said that you were going to ignore wind during this introductory discussion." You're right! I did. I was checking to see if you were paying attention. My point here is that pitch and power work together to move the drone forward and backward. Drift is what is left over from momentum after the pilot, that'll be you, returns the drone to perfectly level flight. Note: I don't think perfectly level flight is possible without a gyro, so don't get discouraged if you find yourself rocking back and forth like a baby-cradle to stay in place...or stay generally in the same football stadium.

Bank—adjusts the lift vector left and right. That's all. Stop here and close your eyes. Okay, bad idea. Read the rest of this paragraph then close your eyes and imagine the three axes that you have to master in order to hover. (And I looked it up, the plural form of axis is axes, even though every time I proofread it, I think of a lumberjack.) Power controls the up and down, pitch controls the forward and back, and bank controls the left and right. It's simple in theory, but try telling that to your thumbs all at the same time.

The Hover Dance

Let me introduce what I call the hover dance before I describe the last control, yaw. In the simulator world as well as in real life with FPV (first-person-view) goggles, it is fairly obvious when the quadcopter is level in bank, regardless of camera angle. What is not obvious without some pointing out and practice is when the quadcopter is level in pitch, forward and back. There is no angle of attack gauge beyond adjusting the tilt of the camera back to zero, which I would recommend doing at first while you break in your hover dancing shoes. There is, however, a clue at either side of your screen to tell you when you are level in pitch as well as a technique to stop your forward or rearward drift. Put yourself in this scenario: you are flying forward and want to stop and maintain altitude. To do so, assuming you are level in bank and not drifting (here's the technique), pitch backward. Yuh-duh, but read me out. This will cause the front of the drone to pitch up toward the sky (pitching up is the same as pitching backward). The opposite is also true: pitching forward makes the front of the drone go down toward the ground. I'm sure I'll slip and say "nose of the drone" at some point, but that's the airplane pilot in me coming out of the hangar. Where was I? Oh yes, the hover dance technique:

  1. Pitch up until the visuals in the side of the screen stop coming toward you,

  2. Then reverse but to a lesser degree. Pitch down until the visuals at the side of the screen stop moving away from you.


At first this cycle will be much larger than you intend, but after a few attempts your hover dance will go from slow-dance style to cha-cha rhythm then onto jitterbug pizzazz.

Yaw—it's how you turn...at first...when you're going slow. Like pitch and power are ever connected, yaw and bank are intertwined. This works out cleverly on the transmitter because to make a level turn, you will be moving both thumbs in the same direction, both left or both right. When you start picking up the pace and zooming through the sky with your camera angle bent up to 35 degrees, you'll start using bank more than yaw to turn, whereas like I first mentioned, at slow speeds you will use more yaw than bank to turn.

An Interesting Activity

Here's an interesting activity if you start stepping on your hover dancing partner's toes and want to try your thumbs at something else. Pick an altitude, pitch forward (down) to get the drone moving forward, then after gaining speed, yaw 180 degrees. You will note that the nose of the quad will go from a down pitch to an up pitch, reflectively. Pitch forward again to level or to get the drone moving forward again, and you have just learned how to reverse course, or stop and turn around without banking.

Now that you can close your eyes and picture Alfalfa from The Little Rascals with his lift vector on top of his head, you can go try out this aeronautical hover dance, and you can give it a go at reversing course. In doing so, you'll be more fascinated than ever by Johnny FPV's performances.

Keep jitterbugging (or hovering)

—Josiah Hutchison


Photo credit from the “Alfalfa Switzer” article on the Our Gang Wiki at Fandom and is licensed under the Creative Commons Attribution-Share Alike License.

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