Charts for Estimating Rotor-blade Flapping Motion of High-performance Helicopters

The theory on which the charts are based does not contain any small-angle assumptions regarding blade-section inflow angles and velocities. These charts are therefore considered applicable, within the limits discussed, for flight conditions involving high inflow velocities and large regions of reversed.velocity. Other than including an approximate allowance for stall in the reversed-velocity region, the charts do not include stall or compressibility effects.