5- 5el APPLICATION Fallout Studies The HASL Aerial Survey System has been used successfully on Operation Wigwam, However, the data is classified and is not in= cluded here. Field tests were conducted at the U. S. Atomic Energy Commission, Nevada Test Site during Operation Teapot, Figure 21 shows the aircraft installation at the operator's position used during these tests. In front of the operator's seat are the control box and the recorder, which indicates aircraft radiation intensities, .The jwece tion box is mounted on the left side of the operator. The recorder, which indicates ground level intensities, was mounted on the right side of the aircraft facing the operator. The Telepulse Coding Station is behind the control box and the radio equipment is ina rack behind the operator's seat. The “Top Hat” detector was moumted in the tail section of the aircraft, Figure 22, where it is most distant from radioactive instrument dials and “sees” only the thin skin of the aircraft between it and the growd. Data obtained over Yucca Flat when flying south, parallel to the main access road, is shown in Figure 23, This data is typical of that which would be expected from a series of localized con= taminated areas. The plane flew at an altitude of 500 feet and telemetored the data to a Central Station located at the Control Point (south) end of the Flat, and the chart shown was taken from the Central Station recorder, While the basic aerial survey technique as developed by this Laboratory has applications to raw materials exploration, civil