TABLE OF CONTENTS An efficient, operational V/STOL aircraft has proven to be an elusive target over the last thirty years.
B. McCormick [454], 1978
V/STOL is an acronym for Vertical/Short Take-off and Landing Aircraft. This category includes aircraft that are capable of performing most of the flight conditions of fixed-wing aircraft. However, take-off, landing and ground performance can be considerably different from CTOL aircraft. Other peculiar problems of V/STOL vehicles are lift augmentation in the terminal phases, transition from vertical to forward flight (and vice versa), operation at high angles of attack, and engine installation. There are, of course, additional performance requirements on aerodynamics, propulsion, structures and flight control systems.
V/STOL aircraft make up the most exotic and unfortunate category of flight vehicle, including several aircraft that never took off, many that flew only experimental tests, and a handful that have entered production. According to McCormick [105] the history of V/STOL aircraft is full of disillusionment.
This chapter will only focus on those peculiar performance indices of real-life V/STOL aircraft, and a few essential concepts for the future. It will not be possible to review the various design options in this class of vehicle. Essential concepts in V/STOL performance are available inAGARD R-710 [455]. In addition, McCormick [105] published an interesting short history of V/STOL flight research, and a book [456] on the aerodynamics of V/STOL. Hirschberg [457] published another historical account of V/STOL research.
