RC Airplane Required Servo Torque Calculation

Use this method for determining the required torque for a control surface on an RC Airplane.
Link to Calculator:
www.radiocontrolinfo.com/info...
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#RCexplained

[@denemesurumu7001]

5:09
Thx

[@alwaysflying6540]

I have 36 years experience in this hobby and I learned something today. I hope this video helps others. Great stuff

[@RCexplained]

I hope so too! Thanks for the comment! Hope to see you out there this flying season!

[@alwaysflying6540]

@@RCexplained I will be there. I've finished old projects and some new. I have a lot of new aircraft to fly. See you soon!!

[@martyw72]

Thank you very much for this video. Very useful information.

[@RCexplained]

Glad it was helpful!

[@lalolicasa1399]

supper. tanks a lot

[@ShawnKnowsEverything]

Could I get the equations used for this calculation? I would like to use it to calculate for surface deflections above 65 degrees.

[@3elmashy522]

no lift is generated just drag you got, if you are interested in calculating it scientifically I recommend ANSYS CFX.

[@agenorberg2606]

Thanks for the video, so instructive. But why is the weight of the plane not an input value? I would say heavier plane gives need for more torque??

[@RCexplained]

Plane weight is not a function of servo torque required for a control surface on a plane.

[@agenorberg2606]

@@RCexplained OK. And I assume that required/ recommended torque is the actual torque to the control surface, if needed torque is 5 kgcm, and the servo arm is 2 cm, you need to buy a servo with 2 x 5 = 10 kgcm?

[@RCexplained]

No the servo arm geometry is cleverly handled by the formula with the inputs given within the calculator.

[@agenorberg2606]

@@RCexplained Hmmh, 🤔 So when you choose servo arm degree, you implisitt choose the arm length…🤓

[@RCexplained]

Yes, the formula in there considers both degrees of rotation on the servo as well as the control surface.

[@PineVanWageningen]

Hi there, if I understand the control linkage correctly, the mechanical lengths play a big role in performance? (servo horn, control surface horn, pushrod, and servo to hinge) The calculator does not provide these lengths. Do you know how I can determine those? Thanks in advance 🤓🙏🏼

[@RCexplained]

Mechanical advantage created by length differences is calculated knowing the difference in angular motions at the servo and control surface locations.

[@richardmiddleton7770]

Two things, 1. When are you ever going to use 15 degrees of elevator at 300kph?! 2. If you use a servo arm length that needs 60+ degrees of travel to get 15 degrees, you will need much less torque.

[@BikerDon2]

How do you choose which holes to use at the servo arm and control horn? Does the hole selection change the torque obtained? Is it just trial and error to get the correct movement and torque required? (Your diagram uses the outer holes for both). I've always wondered this 🤔

[@RCexplained]

Hi Don, use a servo that has the minimum torque required. Using the innermost hole on the servo arm will allow the torque the servo can generate to deliver a greater amount of force.

[@Dennisaj]

Great Video... I sent you an email. I'd love to pay for a one-on-one session before I buy several DC motors.

[@peterbrown6382]

I know this may seem like a stupid question but how does it know the difference in control surfaces. An aileron on my 60 size glow model would be the same size an elevator on a 100cc model and clearly there are different servos. How does that work?

[@RCexplained]

Hi Peter, the control surface formula considers the cord, length, deflection angle of the control surface plus aircraft speed and servo geometry to determine torque requirement. Engine size doesn't come in to the formula nor does the servos that were installed in 2 models. Hope this helps.

[@jeffs7915]

I don't think your discussion was technical enough are you serious can't wrap their mind around on and off switches you're asking them to look at trigonometry? LOL