2.3.2 Altitu. «absorption. The automatic gamma mon. 3s, 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 RACAR OPERATOR 346 i PILOT DETECTOR CONTROL ASSY RADIATION SURVEY —— OPERATOR J [—~- TELEMETER ASSY. ah NAVIGATOR ———} 7 POWER SUPPLY (LOWER DECK) a ali 744 Land RADIO yt TELEMETER RADIO Ba TOR TRANSMITTER oe STEPS ——1 CABLE ASSEMBLY “7 r——— CAMERA HATCH RADIATION DETECTOR ———. |_——— AIRCRAFT 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, pulse- height analyzer, anda recorder, was loaded into the same helicopter. The 28-volt power in the helicopter was converted to 115 volts, 60 cps, by a separate inverter to supply the spectrometer. The count rate at various energy levels was observed on a meter as the base line automatically wideDhdescasechns " swept through an energy scan from 50 kev to 3 Mev. The survey aircraft had the same instrumentation as described in the previous section, plus a scintameter survey meter, TH-3-B. PAE ARCHIVES 2.4 REQUIRED DATA The project operations were directed mainly toward obtaining isodcse plots of the gamma 20 ‘(as 7