FBL Gyro Trex 250 Dfc

[Bozzel]

Hello fellow pilots,

To start off with Im Chris 33y/o from the Netherlands, im new here on the forums. I already watched a lot videos from Tony wich helped me alot understanding things and sorting out some stuff.

A few days ago i reached out to D.O.G. in a private conversation and he recommended me to post this publiuc in the forums aswell so others can learn from it and offer there advice too. So here is a quotation from that conversation.

I'm new to flybarless systems. I bound my DX6i to the spektrum receiver and noticed that my helicopter was spinning slowly counter clockwise when spooled up and was around mid stick, just the point where it should lift off.

First, make sure your tail blades are spinning counter clock wise when spooling up? In the 7200Bx, in letter "F", make sure the tail rotor blades are moving in the same direction as the rudder input. Give that a try and see what happens..

The Gyro direction seemed to look ok. What i didnt change was the Hold and Rate mode in my transmitter. Those where still on 50%. After changing those to 0 > 65% and 1 > 35% most of the spinning was gone. There is still a alight spinning counter clockwise.

Let me know your toughts

Trex 250 DFC
Spektrum AR7200BX 4.0.14
Dx6i

 

[murankar]

First welcome to the forum.


So when setting up or building a tail assembly there is a lot to look for.

During the build process ensure you built the blade correctly. Bearing order and direction make a huge difference. Pay attention to the grip arm and how it's related to the leading edge of the blade. Some are leading edge control and others are trailing edge control. This affects hiwbypu setup your FBL for correction direction. After it's all check the push rod and see how freely it moves. If it's not gliding smoothly then investigate. Finally double check leading edge of the blades and rotation direcrion.

After the build it's all gyro setup. Which you and dog have already discussed. One thing to check is your gain. If your still drifting then raise your main tail gain by points. Hover and repeate until the tail is holding. In rate mode if your tail is still spinning then that's going to be a mechanical setup issue. Correct that by adjusting the push rod length.

 

[Bozzel]

.....
After the build it's all gyro setup. Which you and dog have already discussed. One thing to check is your gain. If your still drifting then raise your main tail gain by points. Hover and repeate until the tail is holding. In rate mode if your tail is still spinning then that's going to be a mechanical setup issue. Correct that by adjusting the push rod length.

I just came back home from work. Hopefully tomorrow its dry so i can take it out for a spin. I took over the heli 2nd hand from someone. He did some good stable 3D manouvres with it. With your info there is only one thing remaining as far my thinking goes. That should be the settings in my transmitter... i might change my settings in my hold mode on my transmitter to solve it. Ill let you guys know my findings.

Thanks so far for all positive feedback can really work things out with this.

 

[Tony]

Some good points made by Ivan and URI. Another thing, that URI hinted at, is mechanical setup so your gyro and servo don't have to work as hard.

Set your gyro gain back to 50% and adjust the tail linkage rod until you are at flying head speed and the tail is stable on the ground. Any throttle or collective input will cause the tail to move just FYI. So do this with a stable head speed. Once you have the mechanical setup done and the tail is stable, then put it back into HH mode at about 65% to start and test fly it.

A good gyro and a good high end tail servo will make all the difference. If you are just learning, the tail is where you want to spend your money. Can't learn collective management if you are constantly chasing the tail.

Edit: Oh, and sorry for the delay.