Rule 35(a) · Restricted visibility
Power-driven vessel making way (fog)
One prolonged blast at intervals of not more than 2 minutes — a power-driven vessel making way through the water in restricted visibility.
every 2 minutes
You hear: 1 prolonged blast.
Meaning
“A power-driven vessel making way through the water shall sound at intervals of not more than 2 minutes one prolonged blast.” Making way means actually moving through the water under power.
Key facts
- Sounded by
- Power-driven vessel making way through the water
- Repeated
- every 2 minutes
- Applies under
- International & US Inland
- Notation
- —
The vessels that sound this signal also show specific lights and day shapes.
Lights & ShapesRelated signals
Source: Rule 35(a) — USCG Navigation Rules (International & Inland)
Rule text is reproduced from the public-domain USCG Navigation Rules. Audio is synthesized to Rule 32 timings.