IHS ESDU Performance reduction for aircraft with turbo-props. "Non-dimensional" graphical method. Level speed. PERF RT1/1

ESDU PERF RT 1/1 illustrates, through a worked example, the correction of flight measured level speed data to conditions of aircraft weight, engine speed and atmosphere different from those at the time of test. Based on the relationship developed in ESDU PERF RT 1/0 the graph plots level speed divided by root relative temperature against engine speed divided by root relative temperature and, in this case, jet pipe temperature divided by relative temperature although it could equally have been turbine inlet temperature or propeller pitch angle. Those values have to be obtained at one value of weight divided by relative pressure to which the graph then applies.