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Search foundations

See the pattern, leg by leg.

A search pattern is a planned sequence of tracks. This diagram illustrates geometry; real search planning also depends on the target, uncertainty, drift, conditions and available resources.

Expanding-square search geometryAn illustrative path growing outwards from its starting point. No geographic coordinates or operational scale.StartEnd of shown pathIllustrative geometry only

Expanding square

In this example, consecutive pairs of legs have the same length. The lengths then increase by one spacing unit: 1, 1, 2, 2, 3, 3 and so on. The drawing starts northwards and turns to starboard; this orientation is only an illustration.

Parallel track

Long, parallel search legs are linked by shorter cross-track legs. This diagram uses a fixed six-unit search-leg length to make the geometry clear. It does not select an operational search area or track spacing.

Questions for a crew exercise

  1. What distinguishes a search leg from a connecting leg?
  2. How would position uncertainty or target movement affect the search plan?
  3. What information would you need from the coordinating authority before starting?
  4. How will the crew record what was actually searched and report observations?
For study, not tasking

This tool does not estimate detection probability, choose track spacing, compensate for drift or produce navigation waypoints. Real searches use the coordinating authority’s plan and your operator’s procedures.