Abstract:

ESDU Perf RJ1/2 discusses the problems of applying graphical methods to flight measured rate of climb results. Ideally a fixed relationship should be chosen between equivalent airspeed and weight and retained for all climbs, each made at a different engine speed. Since that is impossible, it is suggested that a fixed variation of equivalent airspeed with height should be used for all climbs. When best climb speed is adopted at each height, variations in the weight/height schedule between climbs may be ignored. For other schedules, corrections should be made using the analytical techniques of ESDU Perf RJ2/1 before plotting the results as rate of climb divided by root relative temperature against weight divided by relative pressure and engine speed divided by root relative temperature. A worked example shows how such a graph is used to determine climb rate for any ambient condition, aircraft weight and engine speed.