(K, = 220) for 30 tower shots with A 2 100.
line A represents
The horizontal part of
the mean K-factor (Ky = 25) of 40 airbursts.
There
is a substantial difference between detonations on steel towers and
those that are air burst. We consider a burst on a building to be
comparable to a burst on a massive steel or concrete tower; similarly
a treetop burst is comparable to an airburst.
The most critical point
for establishing the dependence of K-factor on building height appears
to be the Trinity shot, analogous to one megaton on a 30-story building.
If wooden towers can be considered analogous to treetop-burst conditions,
several points in the two figures are analogous to treetop bursts.
The
only well-established ones are those for Smallboy and the two Little
Fellers.
For lower elevations we have Koon, whose suspension does not
fit these categories, and Coulomb B, burst on a wooden tower but with
a poorly documented fallout pattern.
For air and treetop bursts, the Subcommittee recommends using line
A in Figures 1 and 2, which amounts to a factor of about 0.45 for
a scaled burst height, 1, of 10. This is uncertain to the extent
represented by the spread in the Small Boy data.
As for bursts on buildings, the available data indicate that
line B should be used, which is to say a height-of-burst correction
of only 0.87 at a scaled height of burst of } = 10. This effect
cannot reduce the K-factor below about 220 no matter how tall the
building.
As in Chapter 1, DCPA needs a K-factor (K,) that does
not reflect reductions for instrument response or ground roughness.
On this basis, the minimum K-factor (K,) for bursts on buildings is
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