Flying coordinated/ Drift Angle Indicator

[Hiob]

Hi folks,

 

I can‘t seem to fly coordinated in the hind.

When I believe to fly coordinated (horizon leveled, ball centered, inertia gun cross in line with fixed cross, bullets flying straight and so on) and I look at the Drift Angle Indicator, it is usually nailed to the left at 40.

When I try to manage the drift angle I usually end up turning.

 

I don‘t have those problems in the Hip. There the Drift angle is usually off just a little and easily correctable.

 

Am I missing something or is the Drift Angle Indicator wip?

[VitMax]

Does your helicopter really drift that much visually? 40 degrees should be very noticeable. If not, then it might be a problem with DISS. Is anything illuminated on the drift indicator? And does it show correct ground speed at the bottom?

[admiki]

Before answering, how is mission set? Any wind?

If you try to fly Huey at max speed of 110+, while in trim you will have quite visible drift to the right.

Try flying in opposite direction and watch drift indicator. That will give you idea whether there is ral drift or gauge is just going crazy.

[Hiob]

No wind, no error indications

ground speed is shown correct.

 

It is a cold start custom mission. Perhaps I didn‘t calibrate something correctly?

 

Edit: I‘m aware of the flight geometry of a helicopter and not completely new to the subject.

As mentioned, I‘m able to fly straight in the huey and the hip.

And I don‘t have strong visual clues of drifting (which is sometimes hard to see in pancake).

That‘s why I suspect the instrument to be wrong, but I can‘t be sure.

 

What‘s the gauge showing for you?

Edited June 26, 2021 by Hiob

[VitMax]

Do you have Airspeed to Doppler switch off on left panel? I'm not entirely sure, what it does, but it seems to mess up DISS.

[Hiob]

I will check…

 

8 minutes ago, VitMax said:

Do you have Airspeed to Doppler switch off on left panel? I'm not entirely sure, what it does, but it seems to mess up DISS.

I don‘t have time to do a cold start now, but I quickly checked with the Caucasus Free Flight IA and could reproduce the quirk by switching this switch.

I used to flick up the whole row in cold start. Perhaps this is the fault.

 

I will mark this as a solution for now. Thank you!

[TomChaai]

The coordinator ball is simply moved around by acceleration, if the ball is off center, it is really un-coordinated and it has nothing to do with Doppler side slip. 
The tail rotor pitch has to be adjusted dynamically with collective and airspeed changes, as torque changes with collective and the sideway lift generated by the vertical stabilizer increases with airspeed. 
In hover you may need the pedal halfway to the right, in mid-to-high speed forward flight, the pedals are close to the center. 
Another thing is that the autopilot yaw channel will try to hold heading in a turn if heading mode isn’t turned on, causing the aircraft to fly out of coordination. In the real thing the pilots step on the pedals to activate a switch to put yaw channel into inhibit/synchronized mode, in this way the autopilot will not attempt to hold heading and keeps the current tail rotor pitch, so coordinated turn can take place. In the game the pedal switch isn’t yet mapped to any controls, so you need to push the pedal a bit to put it to inhibit it. 
 

If it is Doppler angle slips away, but the ball is centered, then the flight is coordinated, it’s either side slip due to crosswind, or a bug when you turn on Airspeed to DISS switch, turn it off. 

Edited June 26, 2021 by TomChaai

[Hiob]

The question was marked as solved.

 

thank you

 

Edited June 29, 2021 by Hiob