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

team by keeping them informed of what is going on at frequent
intervals throughout the search. Competition among crew
members to locate the target helps maintain motivation during
unusually long or difficult searches.
6. SRUs should search at the highest speed consistent with crew
comfort and on scene endurance. Search speeds of up to 120
knots do not significantly reduce visual sweep width for most
targets.
C. The scanning techniques employed can have substantial influence
on detection probabilities and should be adopted to fit the various
search circumstances.
1. The SRU commander should brief scanners on the maximum
expected detection range of the search object for existing
conditions. Scan patterns should be adjusted to include only
areas that provide a reasonable chance of detecting the
target. Valuable scanning effort should not be wasted on low
probability areas. Lookouts should not scan areas beyond the
expected detection range. On each SRU type, visual guides
that aid search crews in improving scan technique should be
identified. Examples on surface craft would be railings,
window frames, or masts, and on aircraft would be wing pods,
engines nacelles, sponsons, and window and door frames.
2. Range estimation can be helped by the same visual guides on an
SRU that aid scan techniques. It is important, especially on
board aircraft where search altitude can change, that scanners
be informed of the lateral distances from the SRU represented
by the projections of wing pods, engine nacelles, and
sponsons, onto the ocean surface. Figure 6-9 illustrates this
concept. Lookouts have a tendency to underestimate distance
to objects, and the greater the actual distance the larger the
error in estimation. {1}
3. SAR personnel tend to scan areas that are beyond the expected
detection range for small (under 30-foot) search targets even
when told specifically that the search object is small.
Almost all small target detections occur within 6 nautical
miles of the search craft (within 1 nautical mile for persons
in the water) at relative bearings between 225 degrees and 135
degrees.