Author Topic: Trim Stick Position  (Read 941 times)

Offline FLS

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Trim Stick Position
« on: September 24, 2009, 10:44:38 AM »
If possible I'd like to see trim change the stick position with Forcefeedback sticks.

Offline Swatch

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Re: Trim Stick Position
« Reply #1 on: September 24, 2009, 12:32:30 PM »
that's not usually how trim works on an aircraft... your stick probably wouldn't see much movement... in fact, your stick would actually be easier to move when trimmed.

Trim typically affects either a trim tab, or a control linkage separate from the stick... Pilots want their stick to be centered at all times since that's where they would take it back to if they want to zero their controls.
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Offline FLS

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Re: Trim Stick Position
« Reply #2 on: September 24, 2009, 12:54:32 PM »
You'll notice in AH that the stick graphic in the cockpit moves with the trim setting. With mechanically linked sticks, taking the pressure off the stick with trim leaves the stick in the position where you were holding it.

Offline gyrene81

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Re: Trim Stick Position
« Reply #3 on: September 24, 2009, 03:24:18 PM »
You'll notice in AH that the stick graphic in the cockpit moves with the trim setting. With mechanically linked sticks, taking the pressure off the stick with trim leaves the stick in the position where you were holding it.
Uhhhh...the stick moves with the trim setting? Have yet to see that happen, maybe you're moving the stick as the trim angle is changed to compensate for the plane moving up or down?

Trim doesn't adjust the stick position...if it does, post whatever plane is doing it in the bug report section.
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Offline FLS

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Re: Trim Stick Position
« Reply #4 on: September 24, 2009, 04:14:36 PM »
It's always nice to hear from experts.  :D

My other wish is that you guys do a little research.

Offline Denholm

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Re: Trim Stick Position
« Reply #5 on: September 24, 2009, 04:27:16 PM »
Am I assuming correctly you want the joystick you are physically touching to move when you adjust the trim? Or do you want the joystick on the screen to move?
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Offline Swatch

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Re: Trim Stick Position
« Reply #6 on: September 24, 2009, 06:51:18 PM »
It's always nice to hear from experts.  :D

My other wish is that you guys do a little research.

If the plane has trim tabs, the stick/column will NOT move with changing the trim in a real aircraft.  Trim is usually used to balance control surface forces.
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Offline FLS

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Re: Trim Stick Position
« Reply #7 on: September 24, 2009, 10:12:30 PM »
Just curious which real aircraft you've flown with a stick.

Offline maddafinga

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Re: Trim Stick Position
« Reply #8 on: September 24, 2009, 11:17:10 PM »
The joystick in our cartoon planes does in fact move when you adjust trim.  I have TrackIR and fly without combat trim turned on.  I see this all the time when I play.  It happens in every plane here that I fly, without exception.

I don't have any real plane experience to speak of though. 

So FLS, when the plane gets out of trim does the center of your stick move correspondingly?  That would indeed be a PITA.  Have you tried turning combat trim on for a second maybe?  Seems like that might recenter the stick to a neutral position if manually trimming it back to center isn't working.  Just a guess though. 
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Offline FLS

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Re: Trim Stick Position
« Reply #9 on: September 25, 2009, 04:29:06 AM »
Madda I'm not reporting a problem. I'm wishing that the FFB joysticks work more like real sticks. When you move your joystick in AH you see the stick move. When you adjust trim in AH with your joystick centered you'll see the cockpit stick move to the trimmed position. This is how real sticks work. Control sticks on WW2 fighters didn't generally have spring centering. You put the stick in the position you need it to be then you adjust trim until it stays there by itself.

Offline maddafinga

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Re: Trim Stick Position
« Reply #10 on: September 25, 2009, 08:46:15 AM »
Ah, gotcha.  It kind of seems like it would just automatically do that anyway.  Especially since the stick in the cockpit does that.  I would have figured that the ff stick would just follow exactly what the stick was doing in the plane. 

If you go on autoclimb, does your stick  keep itself in the somewhat pulled back position, or does it stay centered?
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Offline FLS

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Re: Trim Stick Position
« Reply #11 on: September 25, 2009, 11:22:08 AM »
I think you have the cart before the horse Madda. The controller input is generally matched by the cockpit stick graphic. The exception is the trim setting. This is because joysticks are spring centered which causes much confusion regarding trim. Consider if aileron trim is centered and the stick is centered, there is matched movement between your joystick and the cockpit graphic. Now set aileron trim halfway to the left, the cockpit stick moves over but your joystick is still centered. It seems intuitive that moving your joystick left will now give you more aileron movement than you had before. This is why people think that trimming up helps you to turn better. What actually happens, Hitech please correct me if I'm wrong here, is that moving your joystick all the way left from center gives you the remaining 25% of aileron deflection. Moving your joystick all the way to the right from center now gives you 75% aileron deflection instead of the 50% you might expect. My wish is that the joystick position matches the cockpit stick when trimmed. This is not possible with spring centered joysticks but may be possible with FFB.


Offline Swatch

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Re: Trim Stick Position
« Reply #12 on: September 25, 2009, 01:05:50 PM »
This is how real sticks work. Control sticks on WW2 fighters didn't generally have spring centering. You put the stick in the position you need it to be then you adjust trim until it stays there by itself.

Correct, I think we were just having a misunderstanding (probably on my end).  By setting the trim, you're balancing the control surface forces.  So if you move the stick to a position and then set the trim to balance the forces on the control surfaces, the balanced forces should keep the stick where you left it.

I thought you were talking about trim moving the stick itself as a fine adjustment.  If you are flying with your stick is in a certain position and you change the trim, I thought you were saying you wanted it to trim the control inputs to control the plane, not balance the stick forces.
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Offline FLS

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Re: Trim Stick Position
« Reply #13 on: September 25, 2009, 01:20:37 PM »
OK Swatch, so since the elevator is attached to the stick, and the elevator trim moves the elevator, why wouldn't the elevator trim move the stick as a fine adjustment the way it's modeled in AH?

Offline Swatch

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Re: Trim Stick Position
« Reply #14 on: September 25, 2009, 03:06:15 PM »
Ok, take for example the P-51.

The P-51 had pilot-controlled trim tabs for pitch yaw and roll.  The trim wheels in the P-51 change the incidence of these trim tabs... NOT the entire elevator.

P-51:
Aileron Tab:    http://www.ipmsstockholm.org/magazine/2005/12/images/walkaround_p51_b_017.jpg
Elevator Tab:   http://www.ipmsstockholm.org/magazine/2005/12/images/walkaround_p51_b_018.jpg
Rudder Tab:    http://www.ipmsstockholm.org/magazine/2005/12/images/walkaround_p51_b_023.jpg

Many WWII fighters and bombers had these trim tabs, and that is what the trim wheels are actually changing.
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