Sweep Width Correction (Weather, Speed, Fatigue)
The effective sweep width the searchers actually have: W = uncorrected width x weather factor x speed factor x fatigue factor (IAMSAR / US National SAR Supplement practice). A 120 ft raw detection width in rain with a tired crew (weather 0.5, fatigue 0.9) is a 54 ft effective width - a 55% haircut before the first track is walked. Produces the corrected W that search-track-spacing expects, so the spacing gets planned against real conditions. A planning aid, not a promise of detection.
Formula and source
total_factor = weather_factor x speed_factor x fatigue_factor; corrected_width_ft = uncorrected_width_ft x total_factor; reduction_pct = (1 - total_factor) x 100.
IAMSAR Manual Vol. II / US National SAR Supplement sweep-width correction (W = Wu x f_weather x f_speed x f_fatigue), by name.
Audience
This tile is built for field and sar and the adjacent professions in the Field, Backcountry, and SAR group. The interactive calculator runs entirely in your browser. No account, no fee, no advertising, no tracking.
Related tools
Posture
Rough Logic answers the math question the working professional asks on the job. The site is a calm, fast, ad-free, account-free, ever-free reference. It does not interpret code. It does not replace the licensed professional. It does not store your inputs. The Authority Having Jurisdiction governs all installations and inspections.