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

TABLE 5-6. Visual Sweep Width Estimate for Daylight Detection Aids
Estimated
Sweep
Device Width (NM) SRU Type
Red/orange balloon 0.5 Air or surface
Orange flight suit 0.5 Air
Red hand flare (500
candlepower) 0.5 Air or surface
Day/night flare 0.5 Air or surface
Red pen gun flare 0.75 Air or surface
Red reflective paulin 2.0 Air or surface
Tracer bullets 2.0 Air or surface
Green dye marker* 2.0 Air
Red/orange flag (waving)
(3 ft x 3 ft) 2.5 Air or surface
Sun signal mirror 5.0 Air or surface
White parachute 5.0 Air or surface
Red meteor (star) or
parachute flare
(10,000 candlepower)* 6.0 Air or surface
*Greatly reduced in heavy seas
Table 5-6a. Visual Sweep Width Estimates for Hand Held Orange Smoke {1}
Time on Task (hr)
SRU Type < 3 þ 3
Small boat (41' UTB) 4.6 2.8
Vessel (90' WPB) 6.9 5.0
Air* 7.7
*Sweep width based on test results involving helicopters only.
Searches during the early stages potentially yield a high POD.
Cloud cover, wind, and obscurations to visibility have less
detrimental effects on night detection aids. Even a
flashlight may be seen. On clear nights, pyrotechnics have
been sighted in excess of 40 nautical miles. Sweep width
should be based on the most likely VDSD to be used, and
limited to slightly less than twice the estimated range at
which survivors can detect the SRU. Estimated sweep widths
for night detection aids are given in Table 5-7, 5-7a and
5-7b. Hand held red flare detectability varies by type of SRU,
and also by time on task for surface SRUs. Estimated sweep
widths for hand held red flares are given in Table 5-7a. Life
ring and life jacket strobe light detectablility varies by
type of SRU and time on task, and also by wind speed for
surface SRUs. Estimated sweep widths for life ring/life
jacket white strobes (50,000 peak candlepower) are given in
Table 5-7b.