Teetering Rotor Behavior

[Eli]

When a rotor with a teetering hinge such as a Robinson flaps, does the flapping cause the blade pitch to change with respect to the helicopter as well as the change in angle of attack relative to the air? It seems to me that if the blade were to flap down, there would be a corresponding positive increase in pitch if the swashplate remains fixed.

 

Thanks!

[Over-Talk]

Hi, it's a little hard to understand your question, but I think I see what you are asking.

 

The pitch links are designed/connected in such a way that there wont be a change in blade pitch if the blades flap but the swashplate remains horizontal.

 

Try to climb up on top of a B206 rather than a R22, as it will give a clearer view of how this is engineered.

[Freefall]

Doesn't effect the pitch relative to the blade grip no. If you see where the pitch links are connected to the pitch horn its perpendicular to the mast so that even though the whole head swings up and down the pitch link is at the center of the fulkrum kind of like the middle of a teeter toter.

 

 

EDIT: Over-talk beat me to it

[Cirrus]

Flapping down increases the angle of attack - not the pitch angle.

 

Flapping up - opposite.

[Eli]

Perfect. Thank you.

[epicyclic]

maybe this youtube vid would help.. Minght not but its a good vid nonetheless.