PPRuNe Forums - View Single Post - coriolis effect & static droop
View Single Post
Old 20th January 2001 | 00:59
  #47 (permalink)  
Guest
 
Posts: n/a
Post

Lu,

I agree with all you say regarding the blade pitch response to cyclic position - I should have stated that I was using as simple an example as possible where the pitch change arms would be positioned 90 degrees ahead of the blade pitching axis on a Bell type 2 bladed rotor. In my example, to get the blade low at 12 'o'clock when you move the cyclic forward, the swash plate is tilted to the 3 o'clock as the blade will reach it's low position 90 degrees after the minimum pitch position (I say due to flapping - you say due to precession). We are both on the same piece of paper and if you go back and re-read my post with that in mind you will see we agree.

I was trying to clarify Flapping to Equality as used by Brit Mil and many others as it is not the same as the pitch-flap coupling you described which we regard as the Delta 3 hinge effect. Your previous post stated that the blade was free to feather in relation to the pitch-link which is not the case - it would be impossible to control the aircraft if the blades could increase or decrease pitch except as controlled by the pitch operating arms which are fixed to the swashplate.

You might not like the idea of aerodynamic forces and prefer precession but if it's good enough for the Empire Test Pilot's School (ETPS) who's notes I have read, then it's good enough for me!