Structural Design of a Rotor Blade Having a Spanwise Discontinuity

The structural design of a helicopter rotor blade is based, in general, on two principal loadings – centrifugal force and bending moments in the flapping plane. The first is readily determined for any particular blade; the second is somewhat more difficult. A number of different methods are currently in use for determining the flapwise moment distribution in a rotor blade. They all simply represent different approaches to the problem of obtaining a solution to the basic differential equation. The present discussion concerns the application of the Stuart-Myk1estad method to a blade having a discontinuity in slope or vertical c.g. at some station along the span.