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The airplane (especially the 195) still wants to jump off the runway. The take off trim setting is still not correct.

Is there a TO trim chart we can use? I'm not happy with the flight dynamics. I used 3.0 on TO and then had to go up to 5.0 to keep pitch in the initial climb

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I tried on 190 and it feels better than SP2, but still need quire some force on rotation when on flaps2 and UP3.0.

Once lift off, it feels ok, just a little back pressure to keep on V2+10.

So I might still move the main gear contact point in aircraft.cfg slightly forward.

 

Still, the realword data  shows E190's green band is on 0.5DN to 3.5UP, compare to Feelthere's 0-5UP, and for a somewhat normal CG of 25%, the range should be around 0.5DN-1.0UP, rather than the normal trim around 3.0 on FT, you really only need trim up to 3 when at high weight and CG as forward as less than 10 MAC

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  • 3 months later...
  • 4 weeks later...

(190) is either “all or nothing” with  elevator input on takeoff. You need a lot of elevator to unstick it, then subsequently only very little elevator for the rotate…. otherwise it over-rotates.  I suspect the takeoff pitch trim position needs a high back (up) trim, but too much that it’s outside the takeoff (green) range.  I don’t hand fly this sim much , as use it as a procedural trainer for the real aircraft… but still have to hand fly takeoff obviously until first vertical mode engaged. I laugh every time I takeoff in this aircraft as it’s like a fighter jet 😂 

Also, I’ve setup the pitch trim on my joystick, but if I hold it down for a few seconds - it jumps in 1.0 intervals (rather than 0.1)… so I easy to overtrim.  In real aircraft trim cuts out at 3 secs which I’m used to.. but this happens less than 3 secs. I guess the logic holding trim down for a long time is same as holding the CTL button down to get big change.. which works great for speed, altitude knobs .. but unnecessary for trim.

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On 10/12/2021 at 9:19 PM, justplanemad said:

(190) is either “all or nothing” with  elevator input on takeoff. You need a lot of elevator to unstick it, then subsequently only very little elevator for the rotate…. otherwise it over-rotates. 

Also, I’ve setup the pitch trim on my joystick, but if I hold it down for a few seconds - it jumps in 1.0 intervals (rather than 0.1)… so I easy to overtrim.  In real aircraft trim cuts out at 3 secs which I’m used to.. but this happens less than 3 secs. I guess the logic holding trim down for a long time is same as holding the CTL button down to get big change.. which works great for speed, altitude knobs .. but unnecessary for trim.

I got around the takeoff trim problem in my home cockpit by a small change to the aircraft config file, which I had previously posted on this forum (see copy text below).

I have not experienced the trim switch issue because I used FSUIPC to assign the standard trim up/trim down commands to my yoke trim switch, which gives me realistic operation. 

------------------------------------------------------

I use the E195 exclusively and have spent a lot of time playing with config settings for a better rotation. The two issues for me were the reluctance to unstick at Vr, requiring too much positive trim to achieve rotation, followed by excess pitch up once airborne as result of higher trim setting.

Recently I tried a different approach, looking at the contact points. I reasoned that moving the contact points for the mainwheels forward might help.    Bingo!      

In the aircraft config the standard settings are    point.1    = 1,  -9.0,  -9.0,  -11.75,  2300.0, etc.
                                                                                 point.2    = 1,  -9.0,   9.0,  -11.75,  2300.0,etc.

My modified settings are     point.1    = 1,  -7.0,  -9.0,  -11.75,  2300.0, etc.
                                               point.2    = 1,  -7.0,   9.0,  -11.75,  2300.0, etc.

This change has no effect on visual appearance.  It simply makes the aircraft more willing to rotate at more realistic (lower) trim settings. Where previously it required up to  +5.0, I was able to reduce takeoff trim to +2.0  with a smoother rotation and better transition to climbout.  I have not found any adverse effects from this change.  Usual disclaimer - make a backup of config before editing.

Once off the ground the contact points have no effect on flight dynamics, but the lower trim setting avoids the excessive nose up pitch change after lift off. Landing characteristics are unchanged, but it seems to have a slight benefit of allowing the nosewheel to be lowered more slowly. 

------------------------------------------------------------

I always suggest making a copy of the original config file as a fallback before making changes. 

 

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On 10/14/2021 at 9:15 AM, Biggles2010 said:

I got around the takeoff trim problem in my home cockpit by a small change to the aircraft config file, which I had previously posted on this forum (see copy text below).

I have not experienced the trim switch issue because I used FSUIPC to assign the standard trim up/trim down commands to my yoke trim switch, which gives me realistic operation. 

------------------------------------------------------

I use the E195 exclusively and have spent a lot of time playing with config settings for a better rotation. The two issues for me were the reluctance to unstick at Vr, requiring too much positive trim to achieve rotation, followed by excess pitch up once airborne as result of higher trim setting.

Recently I tried a different approach, looking at the contact points. I reasoned that moving the contact points for the mainwheels forward might help.    Bingo!      

In the aircraft config the standard settings are    point.1    = 1,  -9.0,  -9.0,  -11.75,  2300.0, etc.
                                                                                 point.2    = 1,  -9.0,   9.0,  -11.75,  2300.0,etc.

My modified settings are     point.1    = 1,  -7.0,  -9.0,  -11.75,  2300.0, etc.
                                               point.2    = 1,  -7.0,   9.0,  -11.75,  2300.0, etc.

This change has no effect on visual appearance.  It simply makes the aircraft more willing to rotate at more realistic (lower) trim settings. Where previously it required up to  +5.0, I was able to reduce takeoff trim to +2.0  with a smoother rotation and better transition to climbout.  I have not found any adverse effects from this change.  Usual disclaimer - make a backup of config before editing.

Once off the ground the contact points have no effect on flight dynamics, but the lower trim setting avoids the excessive nose up pitch change after lift off. Landing characteristics are unchanged, but it seems to have a slight benefit of allowing the nosewheel to be lowered more slowly. 

------------------------------------------------------------

I always suggest making a copy of the original config file as a fallback before making changes. 

 

Thanks for taking the time to reply! Your write up perfect describes my experience.  I’ll have a play with the config.  Cheers 

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