Heli has constant left drift

[chrisleematt21]

Started using accurc a bit more it seems like a nice sim but which ever heli I use it suffers from major drift to the left. Its far more than I have experienced with a real one even on a windy day. I have all my trims in neutral, no wind but still have to put in a lot of right cyclic to hold it in position.

Any ideas?

[tomatwalden]

Fast left drift is normal on a heli - but maybe AccuRC overdoes it? I guess if you have zero wind in AccuRC, it will be more obvious. In real life, wind probably means we don't notice the left drift so much??

[chrisleematt21]

Its a lot more than i would have expected far more than any of the other sims i have and far more than i have experienced in real life. I was wondering if it could be a setting issue some where.

[tomatwalden]

This may be useful ?

[trillian]

I noticed that as well. Like it's over doing the tailrotor thrust a bit. I just ignore it and apply whatever correction is needed although it makes me wonder now how much it's drifting in normal flight. I'm liking the feel and realism but still don't have the camera zoom dialed-in and keep having the heli all over the sky.

[chrisleematt21]

I noticed that as well. Like it's over doing the tailrotor thrust a bit. I just ignore it and apply whatever correction is needed although it makes me wonder now how much it's drifting in normal flight. I'm liking the feel and realism but still don't have the camera zoom dialed-in and keep having the heli all over the sky.

The drifting is a bit annoying I will give that vid a go later on as im at work now.

I found the same not sure what needs tweaking with the camera but something does. I think the camera on NEXT is a lot better.

[chrisleematt21]

I emailed AccuRC at lunch and had a response within the hour. Can't fault there support at all not the first time I have emailed them either. I thought I would post their response for every one else.


"We reduced this in version 1.5, the models shouldn't be drifting left at a fast pace unless you are trying to hover them with the rotorhead parallel to the ground ..... which of course is incorrect as the right skid should hang low.

We quite often get this comment as other sims don't simulate any of this stuff properly, so people have become used to seeing the attitude of the heli in sims as rotorhead parallel to ground, which is absolutely not right at all.

There is no way to turn it off, the tail rotor is producing a thrust and the heli will drift left as a result, the only way to stop it would be to turn off the thrust from the tail rotor ..... at which point it's going to spin.

Aerdoynamics is unforgiving in this regard. We have an ongoing discussion about how much torque is going through the model and therefore how much thrust is required to create a steady state, this is where we are likely to make some adjustments as right now the torque is probably marginally high, which results in more thrust at the tail rotor to counter it and a resulting higher left drift.

Solving this is not at all simple, the torque is a factor of a huge number aerodynamic calculations from the rotor head and blades and their interaction with the air, creating drag which in turn requires an input of power from the motor to the rotorhead to overcome that drag, creating a torque. It's a massively complex system and we haven't done it simplistically like the other sims and ignored all the aerodynamics.

It's one of many items that we will improve with time, we don't have a static aerodynamics system, it is constantly being updated and improved, however, this one is not a simple case of just turning something up or down and it fixes itself but it is also not far off being correct as the wattage input we have in the hover is very similar to a real model, the problem is that for this particular element small differences can have a medium sized effect.

We will be updating it but not just at the moment as we are engaged in aerodynamics for quad copters currently and that is taking all the time of our aerodynamics resource."