Detailed Aerial Survey.
Simplified aerial survey information and monitoring reports do not normally
provide sufficient information for the preparation of the detailed
radiological contamination overlay, and a detailed aerial survey is usually
The basis for planning a detailed aerial survey is the checkpoint overlay.
Checkpoints that are easily identified from the air and on a map (small
bodies of water, streams, or road junctions) are selected for the entire
area in advance by the chemical officer (or TOC) representative in
coordination with the aviation officer. These checkpoints are maintained as
an overlay by these two staff officers. Then, when a survey requirement is
established, the control party selects a series of course legs, routes, and
points where data will provide sufficient ground dose rate information to
evaluate the contaminated area.
Figure 4-2 shows an overlay plan for an
aerial survey after a surface burst occurred in the division area.
overlay is to be used with Figure 4-3, which illustrates a division area
with selected checkpoints.
The techniques used to conduct detailed aerial surveys include:
course leg, and point techniques. In using the route technique, the pilot
flies between two checkpoints, following the route of some predominant
terrain feature such as a road that connects the two checkpoints, heavy
In using the course leg technique, the pilot
dashed lines, Figure 4-2.
flies a straight line course (course leg) between two checkpoints, thin
dashed lines, Figure 4-2.
The procedure followed in obtaining dose-rate
information between checkpoints is the same, using either the route
technique or the course leg technique.
When the dose-rate information
obtained from use of either technique is processed, the result is a series
of ground dose rates spaced at equidistant intervals along the path over
which the aircraft was flown. The point technique is used to determine the
ground dose rate at points of operational concern and is normally employed
to obtain more precise dose-rate information at those points than can be
obtained by use of other aerial survey techniques. Processed data from dose
rate information obtained using the point technique are ground dose rates
existing at each of the selected points.
The course leg and point
techniques are described in the following paragraphs.
Procedures for Using Course Leg Technique.
The course leg technique requires that the aerial survey party fly a
straight line course, course leg, between two checkpoints.
maintains as nearly as possible a constant height above the