2.3.2 Altitude Absorption. The automatic gamma monitors, HASL TN-4-C, were mounted
on the YAG-39 and YAG-40. Each instrument was mounted at the end of a boom that was also
used to suspend the depth probe of Project 2.62, The boom extended 35 feet from the side of the
ship and was set at an approximate mean height of 35 feet above the sea. An Esterline-Angus
strip-chart recorder was installed in the shielded control room on the ship, to continuously
record the gamma dose rate. The installation of the monitors and recorders was accomplished
by Project 2.10.
Scintameter survey meters, HASL TH-3-B and TH-7-A, were used for helicopter operations.
Gamma dose rate was measured at various altitudes over contaminated water and land surfaces.
COPILOT
:
PILOT
RADAR OPERATOR TO
RADIATION SURVEY —-~
OFERATOR
oO
DETECTOR CONTROL ASSY.
[.
T-—— TELEMETER ASSY.
a
yj
NAVIGATOR — “TO
bn
|_—— POWER SUPPLY ( LOWER DECK)
ta
J
fp
t
i
SO
RADIO
RACK ATOR
TELEMETER RADIO
,
TRANSMITTER
STEPS ~—CABLE ASSEMBLY —t
CAMERA HATCH
REDIATION DETECTOR ——~
~ A\RCRAFT RADIO
ALTIMETER
Figure 2.3
Radiation-survey-equipment mounting locations
in P2V-5 aircraft.
A gamma spectrometer, HASL TM-10-A, which consists of a scintillation head, pulseheight analyzer, and a recorder, was loaded into the same helicopter. The 28-volt power in the
helicopter was converted
The count rate at various
swept through an energy
The survey aircraft had
to 115 volts, 60 cps, by a separate inverter to supply the spectrcmeter.
energy levels was observed on a meter as the base line automatically
scan from 50 kev to 3 Mev.
the same instrumentation as described in the previous section, plus
a scintameter survey meter, TH-3-B.
2.4
REQUIRED DATA
The project operations were directed mainly toward obtaining isodose plots of the gamma
20