Perfectly symmetrical plane spinning on take off

[Prasiatko]

Any ideas wht this plane is spinning when i try to take off as soon as i reach about 40m/s it veers off to the right and in best case scenario will continue in a clockwise spin on the spot.

 

[Omegagoldfish]

It might be the wheels. Also, double check the center of mass and lift.

 

Is SAS on? That might cause problems as well.

[pincushionman]

Because there's a bug with symmetry not creating symmetrically-stiff structures.

As your aero forces increase, this results in bending and twisting that favors one direction. You'll see this once (if) you get in the air, too; a hard pitch-up will couple with a noticeable roll.

Some things to try:

1) Move your main gear from the wings to the fuselage, and ensure they're pointing straight down. Reducing the number of joints between the center of mass and the wheels will reduce the flexibility and thus the midmatch in flexibility. 

2) Add struts between the wings and fuselage or install the Kerbal Joint Reinforcement mod.

3) Make sure only the center wheel has steering, and re-map wheel steering to a different control than rudder. At speed wheel steering is way too effective, and you're better off forcing (and correcting) turn using rudder only.

4) Invest in a good joystick with a twist grip. This can't fix the problem by itself, but airplanes have different sensitivities in each control axis, and you're in a regime where a tiny yaw input is a very big deal.

And keep in mind wheel flexibility has been borked since 1.1, and I haven't heard anything convincing me that it's beed fixed (only that it's "better") in 1.1.3. I fear until 1.2 gets its better Unity 5 version and wheel middleware, we're stuck with wonky wheels.

[bewing]

Try reducing the friction on the front wheel to .4 or less.

[Prasiatko]

3 hours ago, bewing said:

Try reducing the friction on the front wheel to .4 or less.

Thanks! This worked enough for me to take off albeit still veering off centre down the run way

3 hours ago, pincushionman said:

Because there's a bug with symmetry not creating symmetrically-stiff structures.

As your aero forces increase, this results in bending and twisting that favors one direction. You'll see this once (if) you get in the air, too; a hard pitch-up will couple with a noticeable roll.

 

That explains a lot. I thought i just had really shaky hands on my joystick. Was wondering why increasing deadzone didn't do much.