When rotating, yoke resets to neutral position if I'm pulling up more than 10-15 degrees

[andrey458]

Hello,

 

The issue is when I'm rotating on take off, if I pitch up above 10-15 degrees, the yoke and the elevators just momentarily reset to neutral position. If I reduce the pitch angle (pulling up more gently) the yoke and elevators behave.

 

A few things worth mentioning:

1) The weight is set up to 80-90% of max weight in Xplane 11 Weight and Balance settings.

2) The rotating speed is around 110 knots.

3) CTOTs are on, Conditional levers are on MAX.  (I followed the checklist to the letter)

4) Torque is a little over 100.

5) I'm taking off in T/O and not GRD OPS mode and there are no warnings prior to take off.

 

I am able to take off fine if I rotate extra carefully. So that makes me wonder whether it's a bug or that's how the arplane supposed to behave/behaves in real life. I am expecting speed loss, potential stall, but not yoke and elevators just automatically resetting to neutral position. However, I'm very new to flight simming and aviation in general so please let me know if I'm not making sense.

 

Thank you,

Andrey

[mark70]

That sounds like the activation of the the stick-pusher stall protection system.

For me it's primarily a problem in the landing/flaring fase.

It does seem a little too sensitive, but I don't know how it behaves in the real plane.

 

 

 

[andrey458]

4 hours ago, mark70 said:

That sounds like the activation of the the stick-pusher stall protection system.

For me it's primarily a problem in the landing/flaring fase.

It does seem a little too sensitive, but I don't know how it behaves in the real plane.

 

 

 

Thanks for the response! I wonder if there is something I can do to reduce the sensitivity of this system then. I tested other aircrafts (TBM 900, Beaver, Zibo) and none of them behave this way so I’m thinking maybe I can tweak something with Saab to get rid of this/lower the sensitivity.

 

In addition to that, the speed doesn’t go below 100 knots which I believe is above the stall speed 

Edited March 17, 2021 by andrey458

[andrey458]

I have looked into the systems manual that comes with Saab 340 and it reads (page 183):

 

With the flaps retracted, either stall vane detecting a 12.5o angle of attack activates the stick shakers and sounds the clacker. If no action is taken and both vanes detect an angle-of-attack increase 19 ±1o, the amber PUSH 1 and PUSH 2 lights illuminate, and the stick pusher moves the control column forward.

However, my flaps on takeoff are extended (I tried both 7 and 15 degrees positions), I don’t hear/see the stick shaking at all and the clacker sound is activated only after the stick is pushed forward. 

 

[mark70]

I just saw this in the 1.62 update post:

-Stick Pusher (premature engagement will be revisited in v2.0)

So i guess this is a known issue and will not be resolved until the next major version.

 

Edited March 18, 2021 by mark70

[andrey458]

9 hours ago, mark70 said:

I just saw this in the 1.62 update post:

-Stick Pusher (premature engagement will be revisited in v2.0)

So i guess this is a known issue and will not be resolved until the next major version.

 

Thanks a lot for letting me know! Appreciate it!

[mark70]

Your welcome!

 

[Graeme_77]

@andrey458You said you’re quite new to this, so one of the things that is often very confusing is the misleading concept of a “stall speed”. In short, there really is no such thing without a lot of other parameters also being considered. 

I reported the stick pusher issue after spending a good few days flight testing the Saab model, and while it does kick in too soon, it should not affect you at all when flying normally. Make sure you do not have the experimental flight model select (this makes the situation worse).

It’s worth having a look at this video, you can start at about 9 minutes if you want to skip the theory and see the flight demo. It shows another aircraft, but the concept is the same for all aircraft.

 

[andrey458]

On 3/19/2021 at 3:48 AM, Graeme_77 said:

@andrey458You said you’re quite new to this, so one of the things that is often very confusing is the misleading concept of a “stall speed”. In short, there really is no such thing without a lot of other parameters also being considered. 

I reported the stick pusher issue after spending a good few days flight testing the Saab model, and while it does kick in too soon, it should not affect you at all when flying normally. Make sure you do not have the experimental flight model select (this makes the situation worse).

It’s worth having a look at this video, you can start at about 9 minutes if you want to skip the theory and see the flight demo. It shows another aircraft, but the concept is the same for all aircraft.

 

I actually watched this whole series on TBM 900 (amazing stuff), but somehow missed the extras!

 

I'll take a look! Thanks a lot!