(SOLVED) Is it possible to modify a plane to get variable propeller pitch ?

  • Hello,
    I'm wondering if it's possible to create or modify an existing Aerofly RC8 plane to get variable propeller pitch or possibility to reverse the propeller rotation way. I mean like the Slick 4D plane from Multiplex.
    Throttle half position = neutral (no traction or propulsion)
    Throttle half and above = traction (like normal way to fly)

    Throttle half and under = propulsion (reverse fly)

    Edited 2 times, last by moris (April 23, 2021 at 8:16 PM).

  • You can create a modification using the normal RC 8 editor first. This creates a custom modification TMD and TMC file in your user documents so that you keep the original airplane. Then you'll have to edit these text documents, yes.

    You'll have to add a new receiver output and a new servo for the propeller pitch.

    Then modify the propeller so that it uses the pitch input from that servo.

    Ideally you probably want to swap the inputs for the throttle and propeller speed, so that your normal throttle input controls propeller pitch and not engine rotation speed.

  • Thanks Jan,

    If i'm understanding good your idea : the engine will be controlled by a switch and the propeller pitch by the "Normal" throttle stick.

    That's not what i want : I would like to mix the propeller pitch and engine on the same stick (here the throttle stick). Maybe the function MixHeli is needed in this case ?

    I tried to do something with the SU-29 (see zip file : su29.zip, it comes from : C:\Users\%userprofile%\Documents\aerofly RC 8\aircraft_mod )

  • I still not succeed to get the VPP working on the SU-29.


    Here is what i've done with the TMD and TMC file : su29.zip

    I'm using the "Thrust-Vectoring" function on the 6th radio channel.

    On my radio i mixed the 6th channel with the throttle (channel 3) and put a ratio of 50%.

    In the TMD file, the "aeropropeller" section doesn't contain the PitchControl function. So I added it from a Heli config but it seems that it doesn't operate.

    Here are the parameters in Aerofly RC8 :

  • Only adding the pitch control in the propeller is only part of what is required. You need a separate servo for the control and either a new receiver output and channel or use the existing throttle channel, create a pitch change servo and change the throttle servo so that it's not idle when you go to full reverse thrust.

  • That's what i did :

    Code: Receiver
            <[string8][object][receiver]
                <[string8][Name][Receiver]>
                <[array_string8][ChannelInputNames][Throttle Aileron-L1 Aileron-R1 Elevator Rudder Thrust-Vectoring           ]>
            >
    Code: Receiver input
            <[string8][object][receiveroutput]
                <[string8][Name][PropPitchInput]>
                <[string8][Input][Receiver.Channel6]>
                <[array_float64][Range][-1 1 ]>
                <[bool][ClampToRange][true]>
            >
    Code: Added servo propeller pitch control
            <[string8][object][servoclassic]
                <[string8][Name][ServoPropPitch]>
                <[string8][Input][PropPitchInput.Output]>
                <[float64][Speed][10]>
                <[float64][Position][0]>
                <[float64][P0][0]>
                <[float64][P1][1]>
                <[float64][P2][0]>
                <[float64][P3][0]>
            >
    Code: Throttle stick
            <[string8][object][servoclassic]
                <[string8][Name][ServoThrottle]>
                <[string8][Input][ThrottleInput.Output]>
                <[float64][Speed][10]>
                <[float64][Position][-1]>
                <[float64][P0][-1]>
                <[float64][P1][0]>
                <[float64][P2][2]>
                <[float64][P3][0]>
  • moris April 25, 2021 at 4:40 PM

    Changed the title of the thread from “Is is possible to create/modify a model to get variable propeller pitch” to “Is it possible to create/modify a model to get variable propeller pitch”.
  • The channel "Thrust-Vectoring" is unknown to aerofly, you should use something like glider-engine or other channel names that you can copy from other airplanes.

    PropPitchInput should use the Channel5 if I'm not mistaken. Aerofly, like many computer programs start counting from 0, not from 1.

    <[float64][PitchChange][0]> means you want your propeller pitch to change by 0 degrees. I'd recommend something like 0.3 here, so that the blades actually change pitch depending on the input :)

    By the way, if you haven't found that out already. If you open your tm.log file in the user documents aerofly RC 8 folder you can potentially see any remaining issues when the model is loaded. So for example when an output is not found it shows an error message in the tm.log text file.

  • I made it working ! Thank you for your help Jan !

    You told me "Thrust-Vectoring" is unknown in aerofly but it seems in the RC8 versions it is known.

    Here are the zip file containing the TMD and TMC file of the SU-29-VPP : su29.zip

    (You have to put them in the C:\Users\%userprofile%\Documents\aerofly RC 8\aircraft_mod\su29\ folder)

    To get it working you have to :

    1 - Declare 8 channel on your TX (for VPP, in my case, i'm using channel 3 (throttle) and channel 8 (VPP mixed with throttle stick)

    2 - Assign the "Thrust-Vectoring" function to an available channel in the Aerofly RC8 channel setup.

    In Aerofly RC8, I made VPP working like the SU-29 method, on other plane. Here is the list :

    - Addiction

    - Adrenaline 120

    - Spark

    - Veloxity

  • moris April 26, 2021 at 11:48 AM

    Changed the title of the thread from “Is it possible to create/modify a model to get variable propeller pitch” to “(SOLVED) Is it possible to modify a plane to get variable propeller pitch ?”.
  • For those who want to test some models with the "Variable Propeller Pitch" function, here are the models coming from Aerofly RC8

    Addiction : addiction.zip

    Adrenaline 120 : adrenaline.zip

    Spark : spark.zip

    Sukhoï 29 : su29.zip

    Veloxity : veloxity.zip

    You have to uncompress the zip file in the folder (Windows) : C:\Users\%userprofile%\Documents\aerofly RC 8\aircraft_mod\

    Here is a short footage of the SU29 : Youtube- SU29VPP - AeroflyRC8

    Edited once, last by moris (April 26, 2021 at 5:04 PM).