Modern Helicopter Theory: A Complete Exposition of Up‐to‐Date Ideas on the Principles of Direct Lift Flight Available to Purchase

In this article M. Isacco concludes his exposition of what he believes to be the underlying principles of flight by direct‐lift machines. He here surveys the types that have been built up to the present from the point of view of their stability characteristics. This involves a critical description of practically every helicopter built during the last thirty years. His paper therefore constitutes a history of all that has been done in this field of aeronautics in modern times