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0 votes
asked by (685 points)

I use a lever from the Saitek Quadrant to control the flaps.  The analog potentiometer inadvertently results in mapping the control to continuous flap positions, rather than a finite set of aircraft-specific positions (flap detents).

So, what’s the problem?  When the lever is pushed to its limit for full flap-retraction, it turns out that there remains a tiny unnoticeable amount of flap extension.  Examining the datarefs reveals a “residual value” of less than 0.005.  As the aircraft accelerates beyond Vfe-1, a flap over-speed failure will occur!

Calibrating the lever to include a null zone doesn’t help.

Question: Is there any way to fix this problem?  Any possible tweak in PlaneMaker?

commented by (685 points)

With 11.30r1, I tried using the new Response Curve feature to address this problem.  Unfortunately, it does NOT help.

For example, with the curve’s “Inerp Mode” set to 0.02, just before the flap lever has been pushed its minimum, the output will reach 0.0, in advance.  This is what I expect from the response curve.  However, X-Plane’s dataref still indicate the flap value is at a value of 0.0031—Flap Overspeed will result.

It is very annoying to be getting unexpected, unwarranted, flap failures.  A possible solution, I think, is for X-Plane to simply exempt failure whenever the flap value is under 0.01.  After all, isn’t it realistic for a plane to cruise in one piece while its flap is only 1% extended?

commented by (685 points)

The Flap Axis Detent lua script is the solution.  Found it on 

2 Answers

+1 vote
answered by (1.8k points)
Hey! This should be fixable once 11.30 and the joystick response curve come out. This way you can set the exact position that you want a certain axis to engage, etc.
0 votes
answered by (5.3k points)
Hi disc,

I am not from Laminar Research or XForcePC; just a flight simmer from downunder..

How did you calibrate the unit?  Try calibrating the quadrant just within X-Plane and carry out a complete deletion of  any saitek (Logitech) software.  Have  a look at the following link from Michael Brown who runs a company called XForcePC in the USA.  Laminar Research recommends this business as the only supplier of PCs built for X-Plane within the USA.

The link can be found at

Hope this helps solve your problem

commented by (685 points)

Thanks for your reply, Glenn.  I have never installed any software/driver from Saitek in the first place.  The Youtube video deals with basic calibration technique, so it doesn’t help.

In the Zibo B738 mod, he has an option to calibrate and map the flap controller lever value into each of the aircraft’s detents.  That solved the residual value problem--for the Zibo’s 738.

I wish Laminar could add a configuration into PlaneMaker so all aircraft may have the option to have its flaps rest only at the aircraft-specific detent positions.  Or at the very least, X Plane should exempt flap position value of less than 0.01 from resulting in over-speed failure.

commented by (570 points)
Seems you have an uncalibrated device. Also you can make a different profile for each model or types.
commented by (685 points)

No calibration within X-Plane could guarantee to produce a zero flap value, all the time.  I tried various ways of creating null zone.  Half the time, I would get zero values, other time, values less than 0.01.  Which leads to flap over-speed.

You can actually try this yourself.  Even if you don’t have a Saitek Quadrant, you can temporarily assign your throttle lever to control the flaps.  See if you can produce a zero flap dataref—every time.  If you do come up with an effective calibration technique, please let me know.

commented by (570 points)
I did try with one free axis and found out that you're right. Partially. If I move the axis from a stable position to 0 very fast it will reach 0.

But if I do it slowly it will stay above 0.
commented by (570 points)
commented by (685 points)

Thanks for the confirmation.  Let’s hope 11.30 will come to the rescue.