AC che same cine, it was thought char sufficient energy aight de lost
through radiation in the first thera) pulse that a reduced yield shold be
used,
Therefore, an effective yield of 2 ue was assumed and Sachs’ scalizz
was used to estinuate che bubble size.
By this aethod, sipplemented by ap-
proximate scalicg of rise for icentical cloal size and temperature ratios,
cloud diameter and rise were estiasated.
It was assumed that the cloud dizm-
eter corresponded to the diameter of the fireball; the clacd-rise curves of
TM 23-200 were used.”
Results of this analysis indicated that an evestual
clocd rise of about 120,000 feet could be expected.
The cloud cester should
achieve an altitude of 160,000 feet at GO seconds after burst, while the
fireball cop should arrive at 160,000 feet in about 25 secowds.
Accordingly,
the rockets vere sent through a point above the burst, corrected laterally
for winds at 40, 60, 90, and 120 seconds after zero. The first three samplers
were to penetrate the cloud at 160,000 feer altitade and the 120-secood saapler was to penetrate at 170,000 feet.
The first sampler was expected to
strike the cloud, but it was also intended as a hedge in the event of more
rapid cloud rise than predicted.
The expected cloud dizmeter was of the
order of 50,000 feet.
Debris particle size was again of concern, With the wide dispersion im
plied by the scaling, it was believed probable that the debris would be molec-
ular.
Oa the other band, particulate is often collected after air bursts in
instances where dispersion should have been great.
Either possibility was
expected.
5.1.5
Filter Design for 125,000 Feet altitude
& check calculation of Teak-type impactor performance indicated that this
type instrument would be unsatisfactory for Orange, since high air density,
together with the acoustic limitation of flow speed prevented its effective
operation.
Furthermore, diffusion is less significant at high air densities.
Fine screen, cOO-mesh made of stainless steel, which can use the impaction phenomenon to collece debris was available.
Analysis of the effective-
uess of this type screen icpactor was less thorough than for the impactor
used on Teak.
An analysis of sampling efficiency at ambient conditions for
ac elovetisa of 165,Q0 fect with a venicie speea ot 1560 ft/sec appeared
sufficient.
This wehicle speed corresponds to Mach 1.5.
Such a linited