AIAA- Aerodynamic design of Low speed Aircraft.pdf

AI AA-86-2693 Aerodynamic Design of Low-Speed Aircraft With a NASA Fuselage/Wake- .Propeller Configuration F.R. Goldschmied, F.R. Goldschmied P.E., Monroeville, PA AI ANAH S/AS E E Aircraft Systems, Design ti Technology Meeting October 20-22 1986/Dayton, Ohio For permission to copy or republish, contact the American Institute of Aeronautics and Astronautics 1633 Broadway, New York, NY 10019 AERODYNAMIC DESIGN OF LOW-SPEED AIRCRAFT W I T H A NASA FUSELAGE/WAKE-PROPELLER CONFIGURATION F A B I O R , G O L D S C H M I E D * M O N R O E V I L L E PA 15146 AIAA 86-2693 Abstract 4 A brief parametric study has been carried out on the application of a NASA axismmetric fuselage/ wake-propel l e r configuration , using f u l 1 -Scale wind-tunnel data, t o low-speed general aviation a i r c r a f t w i t h conventional NACA wings . The design matrix comprises t w o wing aspect ra t ios , ( 8 and IO), tHo wing loadings (15 and 21 PSF), f i v e fuse- lage diameters (40, 42, 48, 55 and 65) and f ive corresponding gross weights (800, 1200, 1400, 2400 and 3200 l b ) . The experimental propulsive efficiency of the NASA fuselagdwake-propeller con- figuration goes from 103% f o r the bare fuselage t o a range between 96% and 85% f o r the a i rc raf t . The aerodynamic eff ic iency index ranges from 17.95 t o 11.47 while tha t f o r conventional a i r c r a f t ranges from 7.95 t o 5.00, a s shown by a survey Of 76 general aviation and sport a i r c r a f t . A 50% power reduction, f o r the same gross weight and speed, i s a very practical possibi l i ty . Finally, a specif ic comparison has been carried out between the 55 diameter 4-seat design and one of the l a t e s t 4-seat pusher a i r c r a f t , f o r the same 2400-lb gross weight and 180 MPH speed, yielding 78 HP f o r the former and 180 HP f o r the l a t t e r ; t h i s demonstrates t h a t , while a wake-propeller iS a pusher, a pusher pro