Civilization manualBook 1: From Bare Hands to Steam and Electricity765 entries · 23 phases · 100 years
The Island
Phase 22 — The propeller airplane  /  About year 76
22.20

Radar

radio pulses bounce back from an aircraft or a ship: it is seen in darkness and fog, and its distance is read from a screen

KnowledgeYear 76Stands on 314 earlier

AWhat it needs

Needs 314 other products in all, 4 of them directly.

View

Open a box to see what it needs. A dashed box is a product already drawn in full: click it to jump there. In the org chart, drag to move around.

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