Of course! And also, all blade elements between 0 and 75% are working at higher A.o.A's...you have calculated the AOA od an airfoil in the 75% of the blade. All blade elements between 75% and 100% are working at lower AOA’s.
Observe the curves of the usual NACA 0012. The stall of 8H12 is even earlierHow do you know that an AOA of 12.8º in a blade element is stalled? It depends on the airfoil and
You probably confuse the A.o.A with the pitch setting.in a rotating blade the blade elements are able to fly at much bigger AOA’s than a fixed wing with no stall.
I don't know if in a bad flapping take off condition the retreating blade is stalled or not. What I know is that the entire required flapping movement cannot be achieved, and consequently the dissymmetry of lift is not cancelled.
"Big pressure" is a rather imprecise term...
Can you (or anyone reading this) explain why a hard left bank might cause that?
Would it be less likely in a hard right bank?
Have been following this discussion with great interest. Some great information.
Wryly amused at the earlier description of the so-called 'simple' aerodynamics of gyro rotors.
Yes, we should all know the main causes of blade flap/sailing.
Yes, we should know the indications of blade sail/flap.
Yes, we all should know how to avoid, and corrective actions if encountered.
But I still feel personally that gyro aerodynamics is not simple, and always fully understood by many gyro pilots
When a rotor undergo a continuous rate of roll, it is because the blades produces the necessary cyclic forces, i.e that the control plane precededs the tip path plane with an angle proportional to the rate (fig 1).
When the pilot wants to obtain a continuous roll rate of the aircraft, he tilts the control plane. The roll rate is then constant when the tip plane is symmetrical (fig2)
If the flapping stops have a smaller margin than the control plane stops (*), then they can hit it, but this is safe because here it is only the hand force that pushes the flapping stops against the blades.
(*) The margins of the flapping stops are different between the right and left sides due to the transverse flap angle b1
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A prior-iteration rotary wing forum software initially labeled all new members as JM. Then, after reaching various numbers of postings made by that forum member, the forum "upgraded" their forum subtitle labels. That feature disappeared a long time ago, but the ability to change it to what we wish it to read was also left in the dust.I think it hilarious that Jean Claude, with over thirteen years on the forum and 2,359 always incisive postings, is still given the soubriquet "Junior Member". I am not sure why I am a "Super Member", but some admin person certainly ought to award that to him.
This guy has less than 100 hours in a gyro…he does have apparently over 11000 ( eleven thousand hours in FW) this tells me he must be a professional pilot . ..?Here is caught on video how people do the blade sailing/flapping accidents today
Look at his rotor disc angle as he moves forward. The stick is definitely not all the way back. His pre-rotation is probably 180 to 200 RRPM but then he does not pull the stick back.
Now the rotor RPM does not increase and starts to decrease and then he suddenly pulls the stick back and its game over.
Unless you are doing pre-rotation to 300 RRPM in an AG model with rotorhead 3, you have to pull the stick back before moving forward so fast and if you realize you have not pulled the stick back but kept it centered somewhere, then don't pull it back. Its over. Abort by cutting power to idle and braking and smoothly putting stick forward and start all over again.
It is better than breaking your nose wheel, flipping over and skidding down the runway. In AR-1 not one has flipped over because of landing gear stance and give but the nose wheel gets a load of side load and can break off
This guy has less than 100 hours in a gyro…he does have apparently over 11000 ( eleven thousand hours in FW) this tells me he must be a professional pilot . ..?