JP 3-50 National Search and Rescue Manual Vol I - US Navy

c. The distance that could be covered in 20 minutes for
helicopters.
2. The estimated width is W' = An/1'.
3. The number of required track spacings is n' = w'/S. This
figure is rounded to the nearest even or odd whole number, n.
If n is an even number the SRU completes its search pattern on
the same side of the search area as it started, but if n is
odd the SRU finishes on the opposite side. This factor should
be considered if SRU endurance requires that the end search
point be as near as possible to a refueling base.
4. The subarea width is then w = n x S, and the length is 1 = An/
w.
C. Naming Search Areas. An identification system for use in both
small and large search operations is to label overall search areas
alphabetically. Search areas used in the first search effort are Alfa
areas, Bravo areas in the second search effort, and so forth. Subareas
assigned to SRUs are given a numerical identifier. For example, the SMC
computes the search area for a first search and divides it into three
subareas, A-1, A-2, A-3, for assignment to three different SRUs. If the
first search is unsuccessful, the second enlarged subareas become B-1,
B-2, and B-3.
D. Describing Search Areas. SRUs must be able to plot the search
area on the basis of information received from the SMC. Several
standard methods are used to describe search areas:
1. Boundary Method. Any square or rectangular area oriented
east-west or north-south can be described by stating the two
latitudes and two longitudes. Any inland search area that is
bounded by prominent geographical features can be described by
stating the boundaries in sequence. For example:
a. D-7 Boundaries 26N to 27N, 64W to 65W.
b. A-1 Boundaries Highway 15 to the south, Lake Merhaven
to the west, Runslip River to the north, and Bravado mountain
range to the east.
2. Corner Point Method. This can be used for any area (except
circular areas) that can be described by stating the latitude
and longitude, or geographical features, of each corner, in
sequence. For example:
5-31