Chapter 4
CONCLUSIONS
4.1
RESIDUAL-GAMMA~EXFPOSURE RATE
” The results of the residual-gamma-exposure-rate measurements showed taat for
some devices tne decay exponent varied with both the type of device and the station
location. The decay exponent was fairly uniform for different station locations for Shot
Zuni (1.04 to 1.18) and rather variabie for various station locations for Shot Navajo
(1.07 to 1.39). Althougn no special significance was attached, the spread of values for
the decay exponent seemed to be greater when the average value was high and smaller
when the average value was low.
The residual-instrumentation system perfurmed at about 50 percentof its capability.
This was explained by the failure of the recorders, which were not designed as field
instruments and were used tecause no others were available. There were no known
failures of the Conrad detectors.
4.2
INITIAL-GAMMA-EXPOSURE RATE
Figures 3.27 and 3.28 showthat approximately *# of the total -initial-gamma exposure was delivered after the arrival of the shock front. Insufficient initial-gammarate
or dose data was available to allow independent comparison with published scaling laws.
Figures 3.29 and 3.30 indicate reasonable agreement of both Redwing Projects 2.1 and
2.2 data points with TM 23-290; however, measured dose-versus-cistance curves exhibit a steeper slope than shown on Figure 4-3, page 4-12 of TM 23-200, thus indicating
substantial deviations at short and very long ranges.
4.3
BEACH-BALL OPERATION
This experiment demonstrated the operational feasibility of using the beach-ball
techiique to drop a radiological telemetcr onto a contaminated area.
4.4
THERMAL-RADIATION DETECTOR
The thermal-radiation detector operated satisfactorily for a 5-Mt detonation at a
distance of 20 miles.
4.5
RECOMMENDATIONS
Because of experience gained by Project 2.5 during Operation Plumbbob, it is recommendedthat this experiment, with improved instrumentation, be repeated on other
high-yield events, especially high-yield air bursts.
52