>>If the 90 degree phase lag really was mainly because of gyroscopic precession, then surely the downdraft when applying the cyclic would preceed by 90 degrees. E.G. if your rotors spin clockwise, then appling forward cyclic should create the strongest downdraft on the right hand side. Seems like a fairly easy way to debunk the myth. How they conduct these experiments is their own problem. But playing with my RC heli (which probably feels gyroscopic forces more than most large helis) clearly shows the strongest downdraft at the back.<<
The downdraught change on the upward side would only be a transient effect, as the blades were accelerated upwards. Once they are flapping up it becomes a steady state, i.e. no acceleration so no further increase in downdraught. The place where the upward acceleration takes place is at the rear of the disc
