What pattern is used when the search object is close to the estimated datum position?

What pattern is used when the search object is close to the estimated datum position?

• A. Expanding Square Search -- Sierra Sierra (SS)
• B. Sector Search Pattern: Single Unit -- Victor Sierra (VS)
• C. Circular Search Pattern
• D. Spiral Search Pattern

Answer: (A)

Expanding square search is used when the search object is close to the estimated datum position. The idea is to start at the datum and search in a series of increasingly larger squares, with legs aligned to the cardinal directions. This concentrates initial effort near where the object is most likely to be, then systematically expands the area to ensure nearby locations aren’t missed. The square pattern is straightforward to plan and execute, which helps crews maintain consistency and coverage right around the estimated position. A sector search is chosen when you have directional information or believe the object lies in a specific sector relative to the datum. A circular search covers a circle around the datum, but it’s less efficient for near-datum searches because it doesn’t prioritize expanding coverage in a structured, incremental way from the center. A spiral search expands outward in a continuous curve, which is useful for broader areas, but the expanding square offers tighter, more controllable coverage when the target is near the datum.

Expanding square search is used when the search object is close to the estimated datum position. The idea is to start at the datum and search in a series of increasingly larger squares, with legs aligned to the cardinal directions. This concentrates initial effort near where the object is most likely to be, then systematically expands the area to ensure nearby locations aren’t missed. The square pattern is straightforward to plan and execute, which helps crews maintain consistency and coverage right around the estimated position.

A sector search is chosen when you have directional information or believe the object lies in a specific sector relative to the datum. A circular search covers a circle around the datum, but it’s less efficient for near-datum searches because it doesn’t prioritize expanding coverage in a structured, incremental way from the center. A spiral search expands outward in a continuous curve, which is useful for broader areas, but the expanding square offers tighter, more controllable coverage when the target is near the datum.