đ Key Concepts
⢠Rule 35 â Sound signals in restricted visibility (fog signals)
⢠Which vessel types are grouped together with a vessel not under command for the same whistle signal
⢠Difference between fog signals for a towed vessel, a sailing vessel, and a vessel aground
đ Think About
⢠First, recall the exact fog whistle pattern used by a vessel not under command (number and order of prolonged vs. short blasts). Then ask: which other vessels use that same pattern under Rule 35?
⢠Think about how the Rules group vessels: some âspecialâ vessels (NUC, restricted in ability to maneuver, constrained by draft, fishing, towing, sailing) share one pattern, while a towed vessel and a vessel aground each have their own distinct patterns.
⢠Ask yourself: in fog, does a sailing vessel underway sound the same as a power-driven vessel, or is it included in the special group with NUC and RAM for a different pattern?
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Before You Answer
⢠Verify from Rule 35 (International) which vessels use: one prolonged blast followed by two short blasts.
⢠Check separately what signal a towed vessel (or last vessel of a tow if manned) must sound â note how many short blasts it uses.
⢠Confirm that a vessel aground uses primarily bell/gong signals (with some optional whistle patterns), not the same standard whistle-only pattern as a vessel not under command.