This video answers more e-mails I have received from fans. How big does my servo need to be? The torque calculator mentioned in this video was created from the formulas located in the AMA LMA program document 520-A.
I was thinking about this when l begin to start building my 1/3 Lazer from Lanier, which according to them l require 70oz servos. I feel that this isn’t enough by modern standards as this kit was from the late 1980’s early 1990’s.
Its on page 19 Section 3: Servo Torque part a) Minimum torque = A *Chord *Span * Chord/3 * Servo Arm/Control Arm. A = Airspeed Factor (see Table 2.1) Chord = average control surface chord (root chord + tip chord) / 2 Span = control surface span Servo Arm: the distance from the center of the servo arm to the control linkage attachment. Control Arm: the distance from the hinge line to the control linkage attachment.
So helpful. Thank you. Please also help understand the impact of receiver to servo cable length on servo performance for giant rc airplanes. When you get to like 2meter+ on cable length, does it result in significant voltage drop that the servos may not work. If you address this any of your videos, please do share the link. Would help a lot as I can't seem to find this anywhere. Much appreciated
This outstanding brain food ! Helped me . Are you a quantum mechanic ? I always wonder how the China built big scale foam planes get away with always using 9 g servo all over . Agree ..what are they thinking .
I am new at building RC airplanes. I am building a twin 90mm SU37. It has a wingspan of 1200mm and a length of approx 1700mm. It weighs about 13lbs to 15lbs with lipos. I am using spare parts to build it. The elevators each have a servo that I got out of a Freewing Stinger. Seeing the size, weight, and speed I don't think these servos can handle it. Can some please make a suggestion of what servos I should use? Thanks
Can you tell me the length and cord of the right elevator? Width and length? And what you think the max speed would be of the aircraft? I can figure it out. Thanks.
@@dagtheaviator Thanks for the response. I did a little research and I ordered 30g servos. These servos are used on a Freewing twin 80mm edf MIG 29. It is about the same size and weight of the twin 90mm plane I am building from scratch.
