USCG-ROR-L2.3

Rule 34: whistle signals of intent and agreement

USCG-ROR-M2 · Steering, sailing and signalling: the Inland deltas · USCG-ROR-M2-A Narrow channels, the river rules, whistle signals of intent and agreement, and bridge-to-bridge radiotelephone.

At sea one short blast means **I am altering** to starboard. Inland it means **I intend to leave you on my port side**, and the other vessel answers to agree. The biggest practical difference in the rulebooks.

AI-drafted catalogue content pending SME review. The Rules of the Road examination is the one module where a near miss fails you, and module assignments and pass marks are set by NMC examination policy rather than regulation; verify with the National Maritime Center before booking an exam or relying on any figure here.