ESDU 92006 examines those factors that affect the ease and safety with which an aircraft may be flown. For consideration of aircraft handling, aircraft are divided by class or role indicating the primary purpose of the operation of the aircraft. Within each class, flights or sorties are subdivided by flight phase which describes the type of tasks to be completed. A discussion of piloting techniques and the development of pilot opinion ratings, including the Cooper-Harper ratings, precedes an examination according to the mode of motion (short period, phugoid, roll, spiral or Dutch roll) of the primary parameters that characterise the handling qualities criteria. Extracts from UK current Design and Airworthiness Requirements for Service Aircraft then cover the required flying qualities according to aircraft class and flight phase that define the acceptable characteristics for the control feel in longitudinal manoeuvring flight and for the response in the five modes of motion.