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

642 Aircraft Search
A. Overwater Searching
1. Maximum use of the autopilot allows pilots to devote more time
to searching and keeps the aircraft closer to the track and
assigned altitude. All surface vessels sighted in the search
area should be plotted, noting course, speed, and identity.
If survivors are sighted, these surface vessels may be asked
to assist.
2. Large radar targets are often detected far outside visual
range. If each target is investigated when contact is first
made, considerable time may be lost and the entire search area
may not be covered. When a target is detected at a distance
beyond the assigned track spacing, it should be plotted. If
the plotted position shows that it is closer to a subsequent
search leg than the present leg, it should be identified
later. Small objects should be investigated when contact is
first made as the distance is usually short and they may be
difficult to detect again.
B. Crosslegs
1. Searching with close track spacing requires accurate and
careful navigation. The execution of the crosslegs is
especially critical. The distance an aircraft moves on a
crossleg includes the distance flown on the straightaway plus
the turning diameter of the aircraft (see Figure 6-2). As a
general rule, turns are started 15 seconds prior to the
computed time for the end of the leg. Some autopilot systems
are able to compensate for tight track spacing of short
crosslegs and guarantee desired coverage.
2. The approximate no-wind turning diameter of an aircraft at
various speeds in a standard rate turn (3 degrees/second) is
shown in Table 6-1. The general formula is:
TAS (kts) + 10
________________ = TD
100
6-5