Extreme RangeSlide 2Slide 3Rutan VoyagerExtreme EnduranceExtreme L / DSlide 7Extreme RangeExtreme RangeBreguet Range eq.Breguet Range eq. best values based on current technology:best values based on current technology:pp = 0.9 = 0.9ccpp = 0.4 (piston engine gives the best sfc) = 0.4 (piston engine gives the best sfc)L/D = f (A, e, CL/D = f (A, e, CD0D0)) CCD0D0 = f (S = f (Swettedwetted, BL state, S), BL state, S)0max4DCAeDLfippWWDLcR ln375Extreme RangeExtreme RangeStructural limits to max allowable AStructural limits to max allowable AAerodynamic limits to CAerodynamic limits to CD0D0Powered airplanes: (L/D)Powered airplanes: (L/D)maxmax = 25 very good value ! = 25 very good value !Transports WTransports Wi i / W/ Wff = 2.0 = 2.0RRmaxmax = 14,621 n. mi. = 14,621 n. mi.Nonstop, unrefueled flight around the world Nonstop, unrefueled flight around the world R = 28,000 n.mi.R = 28,000 n.mi. ! ! This range requires a WThis range requires a Wi i / W/ Wff = 3.8 = 3.8 Nothing you can do in a short time to overcome Nothing you can do in a short time to overcome technology limitations! The only thing you can do technology limitations! The only thing you can do is be creative in your design!is be creative in your design!Extreme RangeExtreme RangeRutan achieved WRutan achieved Wi i / W/ Wff = 4.5 in the = 4.5 in the VoyagerVoyager with: with: A = 33.8 A = 33.8 Composites Composites Special airfoils in the lifting surfaces and the Special airfoils in the lifting surfaces and the propellerspropellersPlace fuel outboard on the wing:Place fuel outboard on the wing:Reduce wing root bending momentReduce wing root bending momentImprove WImprove Wii / W / WffExperimental regulations instead of civil or military Experimental regulations instead of civil or military airworthiness constraints, resulting in W savingsairworthiness constraints, resulting in W savingsRutan VoyagerRutan VoyagerExtreme EnduranceExtreme EnduranceBreguet Endurance eq.Breguet Endurance eq. Same tradeoff between L / D and W as in the Same tradeoff between L / D and W as in the case of extreme rangecase of extreme rangefippWWDLVcE ln375Extreme L / DExtreme L / DHigh-performance gliders: Schleicher AS W22 BHigh-performance gliders: Schleicher AS W22 BExtreme L / DExtreme L / D maxmin/1DLmax23min2DLCCSWRODNeed to maximize A and minimize CNeed to maximize A and minimize CD0D0SolutionsSolutions::Very high A wings Very high A wings (Schleicher AS W22 has A = (Schleicher AS W22 has A = 38.3)38.3)Laminar flow wingsLaminar flow wingsMin size fuselage (pilot in reclined Min size fuselage (pilot in reclined position)position)Advanced composite structuresAdvanced composite
View Full Document