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Signal Library

Morse Code

Letters

Numbers

Whistle Patterns

Standard (agree with group)

Ground-to-Air Symbols

Large, high‑contrast symbols (strokes ≥ 6–10 m; 1–3 m wide) with a 2–5 m cleared “halo” around the symbol: V (assistance), X (medical), → (direction), Y/N (yes/no), SOS, F/W (food/water). Place in open areas near handrails.

Rule of Three: Three fires, three flashes, three blasts—repeat with gaps.