Flapback (blowback) = differential lift caused by speed differences between advancing and retreating sides of the rotor disc.
Inflow roll (transverse flow) - differential lift caused by differences in inflow angle between front and rear of rotor disc when tilted in the direction of travel.
In a normal transition gives a nose up and roll towards the advancing side
If you change something in the lift equation - Lift = CL 1/2 rho V squared S then with a helicopter rotor you create an inequality which is compensated for by a change in rotor flapping.
In Blowback the inequality is in V squared, in Inflow roll it is in CL as the inflow angle and therefore AoA changes due to disc tilt.
Excellent info, I’ll have to play around with the lift equation.
Remember inequalities in lift are resolved 90 degrees out due to flapping and aerodynamic damping (very much not due to precession)
So phase lag, not gyroscopic precession? (Another difference I’m trying to better understand.)