POS is described as the probability based on which factors?

• A. POC for areas searched and POD from searching those areas
• B. Weather and sea state
• C. Vessel description and distress type
• D. Time of day and light conditions

Answer: (A)

POS measures the chance of finding the subject during a search, based on how much area has been covered and how likely you are to detect the subject if it’s in the searched area. The two components are the probability of coverage (how much of the search area has been swept) and the probability of detection (POD) within those covered areas. Together, they describe how effective the search effort is at locating the target.

Weather, sea state, vessel description, distress type, and similar factors influence how well equipment and observers perform, but POS is best described by the combination of area coverage and detection likelihood. If you cover more area (higher POC) and maintain or improve how well you can detect a target in those areas (higher POD), POS increases. For example, if half the area is searched (POC = 0.5) with a detection probability of 0.8 in those areas, POS is roughly 0.5 × 0.8 = 0.4, meaning about a 40% chance of locating the target under those conditions.