Revised High-Speed Lift and Drag Data for Clark Y Sections for Propeller Performance Calculations

摘要

Revised drag data have been produced for Clark Y propeller blade sections thinner than 16 per cent thickness/chord. These should supersede the data given in R. & M. 20361;also the range of incidence has been extended to cover small and negative angles for thin sections. The values obtained for the critical Mach number for drag are lower than those given earlier partly because in the present analysis allowance has been made for blade twist and partly because of the previous optimistic interpolations. No alterations have been made to the lift data given in R. & M. 20361 and in R. & M. 22036.nThe analysis is based on 24-ft. wind tunnel tests on various propellers including a 10 per cent 'constant thickness' propeller.