Rules of the Road · Light Arcs — Sidelights
Each sidelight shows an unbroken arc of:
- A112.5 degrees✓ Correct
- B135 degrees
- C225 degrees
- D67.5 degrees
Explanation
Each sidelight (green to starboard, red to port) shows 112.5° — from right ahead to 22.5° abaft the beam on its side. The two sidelights together span the same 225° as the masthead light.
Authority: COLREGS/Navigation Rules, Rule 21(b)
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