TREX 450 pro with flybarless 3GX Module

I decided to go with the TREX 450 Pro V2 3GX because it comes out of the box without a flybar.


At the same time, the 3GX module that comes with it creates questions. 

Is the ArduPilot already designed to perform all of the functions that the 3GX does in terms of decoupling the system using feedback?

Do I put the 3GX module in the loop with the ArduCopter at all, or do I chuck it to make room on the airframe for the rest of the avionics?

I haven't flown it yet, with or without ArduCopter, and I'm not ridiculously experienced with RC in general (I'm using the ArduCopter to test controllers as part of my undergrad engineering project). I'm just looking to avoid any surprises for when my pilot (who is an experienced RC guy) puts the system int he air.

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  • Chris,

         I am in the process of building the T-Rex 450 Pro V2 (3GX) and facing the same problem you had on how to mount the APM 2.5 module to the heli. I guess you have resolved this problem long time ago, could you please tell me how you finally mounted the APM? Will the way you did affect the CG? Do you wrap the APM in the damper foam? The size of APM 2.5 with the servo cables seemed to be much bulky than the 3GX flybarless controller to put in the aft area.


  • You dont need the 3gx if your using an ardupilot (APM) with the traditional heli software. The APM acts as a flybarless controller. 

    Have a look at the main discussion here

    There is also a lot of info on the wiki

    I would try and get some flights on a sim before you fly yours, the APM will always level the heli in stabilise mode but you need to be able to at least hover to tune it.

    Randy has some designs for a plate for the 450 to mount the APM 

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