FUNDAMENTAL considerations which govern the power and fuel requirements, maximum speed, safety, and practical utility of types of VTOL aircraft are enumerated and discussed. The most interesting types of VTOL aircraft such as the helicopter are discussed and evaluated in regard to their probable applicability to the various fields of usefulness in view of these fundamental considerations.
The question whether vertical take-offs and landings are really necessary is considered. It is recognized that there is an advantage in the power-controlled approaches of VTOL aircraft from small airports under all weather conditions.
It is realized that there is research still needed to make the VTOL a more satisfactory aircraft.