the differences in calculated Mode-5 risks for the different values of B would surely
have been less.
Further understanding of why small differences in Ee exist can be gained by plotting
values of the Mode-5 density function computed from Eq. (3) This has been done in
Figure 15 for a range of three miles using values of A and B from Table 21 for
qa. =5,000 deg-lb/ft2. Since Eq. (3) does not include a factor to account for the
probability of a Mode-5 failure, the values plotted in the figure are conditional impact
probabilities per square mile. For the sector from 120° to 180°, which is where most
population centers are located, the density-function value for B =5,000,000 is largest
and for B = 1,000 is smallest. Results consistent with this are shown in Table 21, where
the largest and smallest Ec's are for B =5,000,000 and B =1,000, respectively.




                         ~     ~     00    00 1001~1~100100
                                      Theta (deg)
              Figure 15. Mode-5 Density-Function Values at Three Miles

6.2.3 Effects of Mode-5 Constants on Ship-Hit Contours

In the preceding section, certain values were assigned to Band, by trial and error, best-
fit values of A were found. For every breakup qa. and every B, it was possible to find a
value of A that produced good agreement between theoretical and simulated impact
data over 5° sectors from ±100° to ±180° (see Figure 10 through Figure 13). In some


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