Rotor Blade Visual Model works opposite of Rudder Input.

[EagleEye]

Thanks A16!

 

I did a search and found that:

Yaw:

The coaxial has excellent yaw control, which is done by varying the lift, and more importantly the drag, between the two counter-rotating rotors, while maintaining a constant total lift.

 

During autorotation, the airflow through much of the disks is reversed. A particular pedal input would now cause a yaw in the opposite direction, if it were not for 'pedal switching linkages' that automatically take place in Kamov's at the onset of autorotation.

 

"The problem of coaxial-rotor helicopters' directional stability in autorotation has been solved in full." ~ Quote from Kamov web page, but they do not say how it has been solved.

 

CRAN said ~ "Dr. Gareth Padfield picked the Russian engineers up on this point [weak yaw control during autorotation] at the conference and they sheepishly said that ...'yes, it is a problem, and we achieve direction control in autorotation with the moveable fins...' or words to that effect."

Source: http://unicopter.com/1119.html

Still don`t know how these "pedal switching linkages " work...:(

[Snarf]

One of the effects which happens during an auto rotation is that aerodynamic drag is replaced by drive train drag which is in essence the reverse of the aerodynamic drag. This happens in a normal helicopter too. Thus for a single rotor helicopter the fuselage will want to rotate with the rotor and pedal inputs need to produce a thrust (relatively small one) to combat this.

[P3CFE]

Blade angle movement reversed with rudder input

 

Is there a straight answer allready, to the question if the reversed bladeangle movement with ruddermovement is explainable or a real bug.

 

if its a bug (which is what it seems to me) it should be easy to correct me thinks :) .

 

Thanks for any input.