Tip path plane, forward flight

[heliflyknow]

This question might seem kind of basic but I'm having a hard time understanding what the tip path plane will be in forward flight.

 

Here are the definitions I have, so correct me if I am wrong.

 

Axis of rotation- always perpendicular (90degrees) to mast

Plane of rotation- plane the rotor hub turns in

Tip path plane- path the outer edges of the blades take( parallel to POR)

 

What confuses me is the concept of blade flapping correcting for dissymmetry of lift. How does this change the tip path plane?

 

In my head I imagine the tip path plane/rotor disk just like it sounds, like a dinner plate. I understand there is coning that would make it more bowl shaped but I'm just imagining the outer edge.

 

When you use the cyclic to tilt the rotor disk the thrust is always perpendicular to the rotor disk, so the aircraft moves in the direction that the tip path plane/rotor disk is the lowest. Correct?

 

To gain forward airspeed you use the cyclic to take pitch from the advancing/right side(ccw rotation) and put more on the retreating side in order to tilt the disk forward via phase lag/precession.

 

My confusion comes from the helicopter flying handbook. It says the cyclic makes the blades flap, greater angle of incidence(blade pitch) = up flap, and vise versa.

 

Then later it says in forward flight dissymmetry of lift causes the advancing(right side) to flap up. How can the tip path plane be tipped both forward and to the left(right side high)? Or is it the difference of those two, lowest at the 10/11 o'clock position?

 

The way I see it there are three options to explain what is happening

1. I am overthinking it and it's just low in the front left 10:30 position

2. The cyclic compensates for this dissymmetry by lessening pitch on the advancing size and increasing pitch on the retreating side equalizing the AoA on both sides. This seems the most logical since in every dissymmetry of lift picture/drawing/explanation the advancing/retreating blades have the same pitch angle and I know that's not how the cyclic works.

3. I am oversimplifying the tip path, and it's much more dynamic than I can imagine. I am thinking it's a perfect disk, and it's more like a pickle slice with numerous oscillations during its rotation and it's constantly slightly flapping up, reaching equilibrium, flapping down, and repeating. Maybe the helicopter flying handbook is oversimplifying what is happening during blade flap just to better understand it.

 

P.s. Flapping is a mechanical action right? Meaning it is measurable? It can be expressed in degrees between the blade root/hub and mast

90 degrees = zero flap?

Does that mean cyclic indirectly causes blade flap?

On the ground any deflection of the rotor disk is flapping of the blades?

Is there a difference between rotor deflection/tilt and flapping or is it the same thing?

[aeroscout]

There are a lot of forces on a rotor blade that is in flight. I think it gets all of them except compression, although bending can be described as a combination of compression on one side and tension on the other.