Prop Plane accerating to a point (62 ms) then capping out

[Facepalm]

Im sure this has been asked before but i could not find information on my problem anywhere.

[OHara]

Probably, when the airplane is moving 62 m/s (120 knots) the propeller blades are slicing straight through the air at zero angle-of-attack, so no longer pulling forward.

To make faster propeller aircraft, you probably need a variable-pitch prop.  In KSP you can 'Deploy' the blades and connect 'Deploy Limit'  to an "Axis group" such as the forward/backward axis for wheels.  Then you can make the blades steeper as you gain speed.   

KSP has a strangely narrow range of angles-of-attack where the propellers work well, so you might want to watch lift arrows with the F12 key, to let you know when you have a working pitch angle. 

You would think the "Breaking Ground Discussion" would be the best place, but lately there is more discussion of propellers at general "Gameplay Questions" :

 

 

[Facepalm]

Thank you i changed kal-1000 prop angle from 25 alway up to 45 and im getting much better speed along with acceration. Also not sure if i can f12 on EE but it is handy if there is a way.