Setting Torque and CTOT problem

[^Wolf^]

Hi all,

 

There may still be some people out there that still have trouble with setting torque, CTOT and achieving Take-Off power (and maintaining during take-off). If you are using a throttle quardrant, such as the one CH Products produces, you may be having trouble because of your throttle quadrant, NOT because of the airacraft program itself. So if you are still having trouble please try the following before raising another thread about CTOT, Torque and not achieving Take-Off power.

 

Possible solutions for you. just try these on the runway with the brakes on and focus on finding out if any of the following are a problem for you

 

Potential Solution No. 1

1. Wind your CTOT to 100% (or desired setting)

2. Physically push you Condition Levers on your quadrant to MAX (Use you hand on your real life quadrant, not a mouse on a screen)

3. Push your Power Levers up to where you would normally set it before turning your CTOT on

4. Turn CTOT on (If not working, keep reading)

5. Gently and slowly retard your condition lever back a few milimeters at a time. (Monitor torque gauges and wait for any response)

6. If CTOT begins to work, stop moving your condition lever backwards.

--> Whats happening is X-Plane is not recognising a very small range of you lever position. By moving it backward, the lever now is back in the range that is recognized by X-Plane. By being in the range that is recognized by X-Plane, the CTOT function now knows that it has to send more fuel to the engine. Too far up and CTOT is unable to work out if it needs to send more fuel to the engine.

 

Potential Solution No. 2

1. Wind your CTOT to 100% (or desired setting)

2. Physically push you Condition Levers on your quadrant to MAX (Use you hand on your real life quadrant, not a mouse on a screen)

3. Push your Power Levers up to where you would normally set it before turning your CTOT on

4. Turn CTOT on (If not working, keep reading)

5. Try reducing your power lever. In some cases, up to and possibly more than 20% below the torque setting that is set on the CTOT.

6. Obviously there will be a drop in torque initally, continue reducing vey sowly until you hear the engines spool up

--> What could be happening here is confusion between your throttle quardrant and the program. With the power levers too close the CTOT think that it does not need to send more fuel to the engine (as CTOT can only send MORE fuel to the engine). I've found that with CH Products quadrant you may need to set the Power Levers 20% or more below the required CTOT setting for CTOT to engage.

 

Potential Solution No. 3 (CTOT intermittently working)

What may be happening is the situation described in "Potential solution No. 1."

You may notice at times when you set a lever to a particular position its seems to "wiggle." This is because the potentiometer in the throttle quadrant is between two positions that is determined by the aircraft program. For example the condition lever min-max range may be broken up into 20 individual spots and the computer cant determine weather you're between, lets just say position 15 and 16. so your lever could possibly (I'm not 100% sure) jump between max and the unknown range as described above.

 

All of the above is for PHYSICAL throttle quadrants that people have bought and plugged into their computer. I have a CH Products Throttle Quadrant and I found that the above solutions to work for me. Could be just me. Could help someone now or in the future. Perhaps good knowledge for the makers and support team of the SAAB.  

 

Safe Skies

 

 

[Jorik]

I had the CTOT problem with my CH quadrant.

But what I just found is that the problem was not related to my CH Quadrant.

It was caused by using the GroundService plugin Pushback feature on the LES Saab.

http://x-plane.joanpc.com/plugins/xpgs-ground-services

The CTOT works fine just after a reboot of the GIZMO plugin but when I use the pushback, the CTOT stops working.

This also breaks the engine parameters in flight.

When not using the PushBack all is fine.

I hope this will solve some other people there problem.

And maybe one day we will see a pushback that works on the Saab! ;-)

Kind regards,

Jorik

Edited March 5, 2014 by Jorik

[frankbyte]

Hi

 

I'm having problems with the take-off power as well. When i take off near MTOW, i put the CTOT to about 105 and push the throttles to > 65%  until CTOT takes over the torque to a higher number. But the plane then has a very low acceleration after 60-70 kts and the speed is increasing very slowly after that speed. The result is that i need around 2'200-2'400m of RWY to take off with flaps 15. And i must say that i have a normal joystick, not a CH quadrant.

 

Is this normal or do i'm doing something wrong? I go each time through all checklist before taking off...

 

I would appreciate any help.

 

Thanks and cheers

François

Edited June 4, 2014 by frankbyte

[Goran_M]

This is likely the friction on the landing gear.  This has been changed for the update.

In the meantime, if you know how to make the change yourself, change the "rolling co friction" from 0.185 to 0.123

[frankbyte]

Thanks for your answer! I'm not sure about how to change this value. I suppose i can make it in Plane-Maker? Won't i break something else by doing that (since it is  a complex aircraft) ?