Swerving off runway during takeoff roll - fixed

[Squinius]

I finally worked out how to control the dramatic swerving from one side to the other as I tried to control the takeoff roll down the runway.  It seems I was not getting off the ground quick enough i.e. as soon as I reach 85mph.  Below that speed the tendency to swerve is much less and just about controllable with the rudder.

Hope that's of help to anyone else who's been struggling to get t clean takeoff.

 

Sq.

 

[Sims Smith]

How much payload are you carrying? 

[cpuwolf]

set parking brake, then switch to external view, and look at your nose wheel, try to step on your pedal

we will find this bird slowly reacts on yaw

even if your stability of  sensitivity setting (right side) is 0, it still reacts very slow.

so.....the solution is you have to predict the trends of how aircraft will swing, and use pedal carefully

[Captain_Crow]

Guys,

for me with CH stuff it´s impossible to roll on the runways. Neither at take off nor at landings. I tried it now for several days hours for hours. I for myself have no chance. Simmer since the late 80-ies, but this aircraft is to much for me. I quit. back to the hangar with it. I tried all settings step by step and found out: this aircraft isn´t made for me. I am sorry...

Best

Steff

 

[Sweet19blue]

The best I could do was to set Takeoff power all along before releasing the brakes on takeoff. But landing is another story. It is really crosswind that is hard to keep the aircraft rolling straight during takeoff and landing. It is manageable if the wind is calm and fairly in the runway axis.

Pierre

[Goran_M]

39 minutes ago, Captain_Crow said:

Guys,

for me with CH stuff it´s impossible to roll on the runways. Neither at take off nor at landings. I tried it now for several days hours for hours. I for myself have no chance. Simmer since the late 80-ies, but this aircraft is to much for me. I quit. back to the hangar with it. I tried all settings step by step and found out: this aircraft isn´t made for me. I am sorry...

Best

Steff

 

Try adjusting hardware sensitivites.  It really isn't difficult to take off.  There are many videos on youtube of people doing complete flights with it. 
Also, make sure the yaw damper is definitely off for both take off and landing.

 

[Captain_Crow]

1 hour ago, Goran_M said:

Try adjusting hardware sensitivites.  It really isn't difficult to take off.  There are many videos on youtube of people doing complete flights with it. 
Also, make sure the yaw damper is definitely off for both take off and landing.

 

Dear Goran,

I did all of this. Again and again. It seems this aircraft ist made for better pilots than me. I never had such difficulties to handle a machine since ever. I just want to fly an aircraft not fiddeling around to get it run straight forward on ground for days and days. Thats not my intention using simulators. So, as great as this aircraft is made by you. I am out for that.

Thanks and best wishes.

Steff

[Goran_M]

We still want you to enjoy it.  what about setting the parking brake and spooling the engines up, then releasing the brakes and letting it roll down the runway without touching the rudder?  It doesn't take much to take off.  
Could you at least try that for now?

 

[RobW05]

I'm also struggling with it. I have zero real world experience so I won't argue if it's realistic or not. But I think it depends a lot on the hardware, my Thrustmaster pedals seem to be just crap. (although, i also never had such big problems with other planes)

When I really try and concentrate hardly on staying on the centerline i do have success most of the times. But then I get in trouble with watching speed and throttle settings. Because of the design of the throttle (*) we only have half the axis to control power and you have to move throttle very carefully. Mix in some nasty crosswind and I'm completely off. 

* Regarding throttle design: Do you think it would be possible to implement an option to control the alpha range with one full axis, and beta + reverse with a second axis? That would make power management a lot easier. 

[Captain_Crow]

Dear Goran,

I highly appreciate you engagment. I remember we had a chat years ago at my first visit on x-aviation and you suggested the SF340 to me, which I immediately purchased after the chat. So I know that you are serious in clients relations. But my time to use the simulation is short, and if I go into the sim, I just want to fly and learn about systems, handling IFR stuff using Vatsim etc. I have no fun to test all the time, what I did with the TBM, knowing that this bird is obvously the best in its class for X-Plane. Yes it is. But unfortunately not for me. It is how it is.

Thanks again

and best wishes

Steff

[ZE1011]

As in the real world you have to be very gentle on the rudder pedals, if you go stamping on them left to right to correct the movements you will make it worse. You need to apply constant rudder pressure to compensate for the propeller torque rather than chasing the nose with the rudder pedals. Focus on the END of the runway and not over the cowling and make small applications of rudder. I have never flown a turboprop IRL so cant comment if the amount required is correct for this ac type, but I fly a Socata tb9 and have flown pipers and the principle is the same. Hope that is of some help!

[quijote]

In reading the documentation for the real TBM900, I saw an entry in the checklists to turn on Nose Wheel Steering. I saw it only once although I still have 400 pages to go. My TBM doesn't respond at all when I twist the joystick (unlike most of my other planes) - all steering is done with the rudder pedals.  And those over-react severely.

I have got to think that the real TBM doesn't react to the steering like the sim version. Surely there are adjustments that can be made in the acf file?

[Goran_M]

51 minutes ago, quijote said:

In reading the documentation for the real TBM900, I saw an entry in the checklists to turn on Nose Wheel Steering. I saw it only once although I still have 400 pages to go. My TBM doesn't respond at all when I twist the joystick (unlike most of my other planes) - all steering is done with the rudder pedals.  And those over-react severely.

I have got to think that the real TBM doesn't react to the steering like the sim version. Surely there are adjustments that can be made in the acf file?

Please don't adjust anything in the acf.  There is code driving the ground handling of the TBM, and any adjustments might cause serious issues.

You could try adjusting your hardware in the sim.

[codylang]

As some say...Try it with parking brake set...Power up to 40... Release brakes...gradually bring power up to 80 or so and light movement on the rudders. I too had this problem at first which about drove me nuts..but then decided to be a little more patient with the take off role...Now it doesn't happen to me as much and also can keep it down the center line...Just remember if youre using rudder to keep on the runway...right before rotation you'll have to compensate the rudder with aileron..if not either wing will dive off towards the ground as soon as you get airborne.

[MrCSone]

What I found is that I need to "recalibrate" my rudders every time I load the sim and the TBM. I just push the controls completely in each direction once. Otherwise even the slightest movement of the pedals results in huge inputs in the sim. Hopefully that helps some of you.

Edited December 3, 2018 by MrCSone

[ZE1011]

Also check your rudder trim, if you did not check it in your pre-flight it will be where ever it was left on the previous flight. 

[Mateyhv]

On 12/3/2018 at 5:04 PM, MrCSone said:

What I found is that I need to "recalibrate" my rudders every time I load the sim and the TBM. I just push the controls completely in each direction once. Otherwise even the slightest movement of the pedals results in huge inputs in the sim. Hopefully that helps some of you.

XP11 issue, happens to me every time with the left aileron. If I don't move it to full extension on the ground even the slightes movement makes it snap full left. Not sure why this "every start up" calibration is needed. X52 Pro joystick here.

[CDNCAVOK]

On 11/22/2018 at 4:16 AM, Captain_Crow said:

Dear Goran,

I did all of this. Again and again. It seems this aircraft ist made for better pilots than me. I never had such difficulties to handle a machine since ever. I just want to fly an aircraft not fiddeling around to get it run straight forward on ground for days and days. Thats not my intention using simulators. So, as great as this aircraft is made by you. I am out for that.

Thanks and best wishes.

Steff

@Goran_M

Hello Goran. 

Look at Jason's rudder setting on take/off in the HotStart TBM  at 25:22 https://www.youtube.com/watch?v=zExCWZWKe-I&t=446s . His rudder trim is centered which would probably send him careening off the runway in his real TBM! They are not set as they are supposed to according to the TBM Instructional video here https://www.youtube.com/watch?v=o8sc3VlZPUc  at 5:21. The rudder should be set in the green!  In the HotStart TBM I also have to set the rudder trim just a little right off the the center to have any chance in taking off straight! Some folks put it half way between the white and green indicator. That does not work for me and forget about setting it on the green indicator (as it should). 

I love this bird but something is still off about it’s ground handling on t/o. 

I took the time to make a very detailed video of 6 takeoffs in zero wind. I use a Saitek Aviator Joystick with rudder twist which is not ideal.

https://www.youtube.com/watch?v=3hzY14ExzRQ

 

Cheers

Edited December 16, 2018 by CDNCAVOK
Added Video

[RobW05]

I had trouble controlling the TBM on takeoff and landing, but now I think managed to get it under control.

How did I achieve this? 

1. Before taxi, I push the rudder to its limits on each side multiple times. I noticed that occasionally the rudder won't follow my input smoothly, you can then even see the pedals jumping a bit when you look down. Moving my rudder axis to its limits a few times fixes it.

2. As it was already mentioned by CDNCAVOK, I don't follow the instructions for rudder trim. I put it somewhere just slightly right of center. (If I follow the instructions I find myself counteracting with left rudder once a certain speed was reached.)

3. And finally, I am now using Active Sky for weather depiction. Active Sky has an option to overcome xplanes turbulence model and I think that was what finally resolved all remaining control problems on my end.

So I think the biggest part of the squirrelly takeoff runs is still on xplane side, maybe with the sensitive controls of the TBM contributing. (plus noisy hardware axis) 

 

[CDNCAVOK]

13 minutes ago, RobW05 said:

I had trouble controlling the TBM on takeoff and landing, but now I think managed to get it under control.

How did I achieve this? 

1. Before taxi, I push the rudder to its limits on each side multiple times. I noticed that occasionally the rudder won't follow my input smoothly, you can then even see the pedals jumping a bit when you look down. Moving my rudder axis to its limits a few times fixes it.

2. As it was already mentioned by CDNCAVOK, I don't follow the instructions for rudder trim. I put it somewhere just slightly right of center. (If I follow the instructions I find myself counteracting with left rudder once a certain speed was reached.)

3. And finally, I am now using Active Sky for weather depiction. Active Sky has an option to overcome xplanes turbulence model and I think that was what finally resolved all remaining control problems on my end.

So I think the biggest part of the squirrelly takeoff runs is still on xplane side, maybe with the sensitive controls of the TBM contributing. (plus noisy hardware axis) 

 

Great additional feedback. I was not aware that AS was already released!

[CDNCAVOK]

Here is what Jason (beta ester and real world TBM 900 pilot ) had to say:

 

 

[Jakob Ludwig]

I did several takeoffs yesterday and can confirm that you can achieve a better directional control during the take-off run using none to very little right rudder trim. That has changed a bit with version 1.1.3 on X-Plane 11.30

[cmbaviator]

for those having ASXP, just enable to turn down the crosswing component on the ground ( still maintain HD/TL wind component), will be be easier to take off and land during corsswind