Sec. 55.5 



APPENDAGE-RESISTANCE CALCULATIONS 



291 



having an aspect ratio of 2.5 [RPSS, 1948, Fig. 

 216, p. 326]. 



55.5 Lift, Drag, and Other Data for Typical 

 Bodies Representing Appendages. Appendages 

 are also classified by types or shape of body, on 

 the basis that, if they resemble certain geometric 

 forms, there are 0-diml drag coefficient data 

 available in the Uterature by which their resist- 

 ances may be approximated. The shapes in this 

 category include symmetrical and asymmetrical 

 airfoils, fuselages, and other parts of airplanes 

 and airships, for which published drag data are 

 rather extensive. For example, W. S. Diehl gives 



Form of Body 



Sphere of p/' ^•\___U_ 

 Diameter J) 



Hemisphere, "jT 

 ConcQve to 33 

 Stream j. _^ 



Hemisphere, "y 

 Convex to D . . , 

 Stream JL V 1^ 



Ellipsoid, 

 Major Axis 

 -L to Flow 



Form of Bodvj 



Circular 

 Flat Plate, 

 Normal 

 Stream 



^IC^ 



Recto ncjular 



Plote, 

 Normal 



to Stream 



^b- 





.1 



1-" K-T: 



Circular Cylinder, 



Axis Ffarallel to Stream 



T- 



Circulor ^ 

 Cylinder, I 

 Axis 



Perpend icubr to Stream 



2-Diml Strut of Elliptic 

 Section _ 



2.-Diml StreomlJned Strut 



Dimension 

 Ratio 



l/d-0 



1 

 £ 

 3 

 A Pfoj'acted 



^-i 



^-0 

 1 

 2 



4 

 7 



L/D" 1 



z 



5 

 10 

 20 

 40 



L/d-5 



c/t. 



Re\(nolds 

 Number 



Drag 

 Coefficient 



=>I0' 



>I0' 



>I0^ 



>\0^ 



>5(l0') 



Abt6(l0*) 



1,16 

 1.20 

 1.50 

 1.90 



1.12 

 0.91 

 085 

 087 

 099 



0.63 

 0.68 

 074 

 0.82 

 090 

 98 

 1.20 



0.35 

 0.34 



0.20 



QIO 



0.06 



0.063 



Q094 



Ellipsoid, XI f^ )\<^ 

 Mojor Axis i Is^.^^ 

 II to Flow J, i_ U- 



Dimension Reynolds Droq 

 Rotio Number Coefficient 



^M.8 



10= 

 3(10^) 



>I0^ 



>I0^ 



<50o») 

 >5(I0») 



>2(l0') 



0.50 

 0.20 



0.60 

 021 



Fig. 55. B Drag-Coefficient Values fob a Number 

 OF Well-Known Geometric Shapes 

 The velocity vector U indicates the direction of uniform 

 flow in each case 



Fig. 55.C Drag-Coefficient Values for a Group 

 OP 3-DiML Geometric Shapes 

 The velocity vector U indicates the direction of uniform 

 flow in each case 



drag and moment data on a great variety of these 

 elements, as well as on seaplane and flying-boat 

 hulls ["Tests on Aeronautical Fuselages and 

 Hulls," NACA Rep. 236, 1926 reports, pp. 131- 

 150]. S. F. Hoerner, in his book "Aerodynamic 

 Drag," 1951, devotes his entire Chapter VIII, on 

 pages 121-155, to the drag of aircraft components. 

 He also gives a vast amount of 0-diml drag data, 

 applicable to appendages in water, in other 

 parts of the book. 



Figs. 55.B and 55.C present the readily available 

 geometric-shape data, with the values necessary 

 for insertion in the 0-diml drag formula 



D = Cr,^Ar,„,U' 



Here Ap,„j may be 0.25tD\ 6(/i), L{D), or b(t), 

 as the case requires. These data are adapted from 

 the^foUowing sources: 



(a) "The Physics of Aviation," 1942, p. 75 



(b) Van Lammeren, W. P. A., Troost, L., and Koning, 



J. G., RPSS, 1948, Fig. 26, p. 52 



(c) Rouse, H., EH, 1950, Table 2, p. 126; also Fig. 90 on 



p. 124. 



