tail issues

[kevinh]

My TREX XCDE has a 401 and a 3154 on the tail.

when applying throttle the tail has a tendecy to go to the left as the throttle is applied in heading hold mode

any thoughts?


gyro settings are

54% normal mode and hh is also 54%

ive tried altering the gain but it still does it.

[robgt]

Is Revo Mixing inhibited in your Tx?
Cheers,
Rob

[kevinh]

did think of that and double checked it and its inh in the TX

[robgt]

Do you use a throttle curve or is it a governed headspeed?
Cheers,
Rob

[robgt]

Also - what Tx are you using?
Cheers,
Rob

[kevinh]

Throttle curve & FF8. Ta.

[robgt]

Do you get a headspeed surge when you add pitch, inducing the tail drift?
It seems this might be the likely candidate...

You could try activating the governor on the ESC, or increasing the gain on the gyro to help combat it (though increased gain may bring on some fast wagging if it's already close ot the gain limit).

Can you post your throttle curve please - do you use IdleUp or do you fly in Normal mode?

Cheers,
Rob

[kevinh]

sorry didnt get back sooner been driving to manchester tonight to go to work


dont use idle up

throttle curve is 0-30-65-85-100
pitch curve 50-55-66-70-78

which relates to 0 pitch on the bottom stick and 9 degress at the top
5.5 degress middle stick

cant activate the govenor at the moment im using a jetix speed controler as the align is with Revolution models as its packed up, hopefully will get it replaced under warranty

The align speed controller is only the basic 25 amp model which hasnt got the govenor fitted if my memory serves me correctly

[kevinh]

Even the 25a speed controller has a governor fitted,

but its not fitted yet as picked up a new 1 from revolution models

i think the headspeed is the issue, there is a increase in head speed.

i think i will decrease the throttle curve slighlty making it a even curve 0 25 50 75 100

[kevinh]

This is still happening and started to annoy me now, tried different head speeds different gyro gains and its drifting badly to the left and everytime i raise the throttle the tail spins to the left.

Any other suggestions?

[nightstalker]

On the tail servo how far out do u have the ball??
A friend of my has the mini titan and it was doing the same thing and we move the ball as close to the centre as poss and upped the gain and it fixed it so well he was doing hard power outs and it held spot on.

54% is very low its 4% just in HH if u went below 50% u will be in normal mode

also might sound silly but the gain is set the right way??

[robgt]

Sorry - been away
Probably the best bet is to use the governor as I believe the throttle is surging, using your throttle curve, causing this rudder swing.

Try enabling the throttle governor on the ESC and then setting a throttle curve like this:

0-80-80-80-80

With the governor enabled, you can spool up the heli slowly and controlled by moving the throttle stick to about 1/4 stick (according to your pitch curve - so it doesn't try to lift off until the headspeed has settled at 80%) and letting the headspeed catch up naturally (the governor takes care of it for you).

Cheers,
Rob

[nightstalker]

I don't think its to do with the ESC, if he was getting to much power in one go then it would make the tail go to the right eg: torque, but hes stating it goes to the left opposite to the torque, so i think its something to do with the gyro so check to make sure the gain is set the right way as you might have it in reverse.

[kevinh]

Ill tried the ball outwards not inwards towards the centre,ill try that as well.

What do mean about the gyro gain setting? do you mean altering the right 1 as in normal or HH mode, at the moment the red led is on permantly on the 401 saying its HH mode,

Ive upped the gryo all through the range from 54% to over 100% and it still does it

[nightstalker]

On the 401 on the top u have a switch that say reverse or normal, just make sure the gain is working the right way.

To check switch on and hold the tail and push the tail to the right, now when u do this the slider on the output shaft should move out and if you move the tail to the left the slider should move inwards

Have a look at this pic


new.jpg