THE AERODYNAMICS OF A SPINNING SHELL. 
309 
Table I.—Experimental Values of the GWple Coefficient fu{ v /a), the Normal Force 
and Cross Wind Force Coefficients f N (v/a) and / L (t)/a), for Shells of Form A, 
fig. 6 ; also Values of / M (v/a) for Shells of Form B, fig. 6. 
Determined by firing trials with 3-inch shells. 
v/a. 
Shell of form A. 
Form B. 
7m (v/a). 
7n (v/a). 
7l (v/a). 
7h («/<*)• 
Wind channel. 
8-57 
3-34* 
3-0* 
8-95 
0-7 
8-6 
— 
— 
9-05 
0-8 
9-05 
4 3 
3-9 
9-75 
0-9 
10-35 
— 
— 
11-15 
10 
11-55 
5-2 
4-6 
11-7 
11 
11-4 
— 
— 
11-6 
1-2 
11-1 
3-5 
2-6 
11-35 
1-3 
10-8 
— 
— 
11-15 
1-4 
10-55 
4-1 
3-1 
11-05 
1-5 
10-3 
— 
— 
11-0 
1-6 
10-05 
4-3 
3-35 
11-0 
1-7 
9-85 
— 
— 
10-95 
1-8 
9-65 
4-5 
3-6 
10-95 
1-9 
9-4 
— 
— 
10-90 
2-0 
9-15 
— 
— 
Eig. 6. Showing the external contour of the 3-inch 16-lb. shells, Design H.E. Mark IIb, used in the trial with 
(1) No. 80 fuze, Mark III; (2) 6 C.R.H. plug, Design 25420. 
Note .—The driving hand is shown cut off at a diameter of 3 - 02 inches, its mean diameter after engraving. 
* Uncertain. 
