Marine VHF Radio: The Working Guide

The most consequential 30 seconds of any cruiser’s life are the 30 seconds in which they transmit a Mayday. The Coast Guard’s Pacific Northwest assets — Sector Puget Sound, Sector Columbia River, the air stations at Astoria and Port Angeles, the small-boat stations spread along the coast — are listening on Channel 16 right now. They will respond. The variable is whether the cruiser knows what to say, in what order, on which channel, with which information.

This guide covers what to say. The first sections are the working procedure for every kind of call: routine, urgent, distress. The later sections are PNW-specific: ferry traffic, the Strait of Juan de Fuca traffic separation scheme, the Canadian channel pattern, NOAA weather frequencies. Channel 16 is the same everywhere. Everything else has regional flavour.

What VHF is, briefly

Marine VHF (Very High Frequency, 156–174 MHz) is a line-of-sight radio system designed for short-range vessel communication. Range depends on antenna height: a fixed antenna at the masthead on a 35-foot sailboat reaches roughly 20–25 nautical miles to a similar antenna on another vessel, and 30–40 nautical miles to a USCG shoreside antenna. Range to a handheld VHF in a person’s hand at deck level is closer to 5 nautical miles.

The system is reliable, simple, and governed by a tight set of international protocols. It is the primary communication for the US Coast Guard, ferries, harbour patrols, commercial fishing fleets, and recreational boaters. In the PNW, every commercial and recreational vessel of any seriousness has a VHF on Channel 16.

The channels you actually use

Channel 16 is the channel everyone listens on. It is not the channel for conversation. Initiate on 16; move to a working channel; complete the conversation; close the contact. Channel 16 stays clear for distress calls, USCG broadcasts, and initial contact only.

The DSC system

Every VHF manufactured since 2000 has DSC — Digital Selective Calling. The radio is assigned a unique nine-digit Maritime Mobile Service Identity (MMSI), registered with BoatUS or directly with the FCC; modern radios are wired to the boat’s GPS. A press of the red DSC distress button transmits an automated digital alert on Channel 70 containing the MMSI, the GPS position, and (if the cruiser had time to select it) the nature of distress. Every DSC-equipped receiver within range — every commercial vessel, every USCG shoreside station, every modern recreational boat — gets the alert and the position simultaneously.

DSC is the reason Coast Guard SAR response times in the PNW have improved dramatically since 2000. The cruiser who triggers DSC has, in roughly two seconds, told everyone within radio range exactly where they are. Voice Mayday on Channel 16 follows immediately. Both. Not one or the other.

If your VHF radio does not have DSC, or is not wired to the GPS, or has no MMSI registered, replace the radio.

Routine calls

Listen for 5–10 seconds. Then:

1. Press transmit.
2. Say the called vessel’s name three times.
3. Say “this is” and your vessel’s name once.
4. Suggest a working channel.
5. Release transmit. Wait.

Example: “Sea Bird, Sea Bird, Sea Bird — this is Wanderer, Channel 9. Over.”

If contact is made, switch to the working channel. Conversation there. Close the contact when done: “This is Wanderer, out.”

Two corrections to common bad habits:

Do not say “Roger out.” Roger means I understand; out means the conversation is finished. Together they are redundant. Just out.

Do not use ten-codes. Ten-four is police-radio code, not maritime. The maritime equivalents are roger, copy, wilco (will comply), over, out. Use them.

Urgent calls — Pan-Pan

For situations that are urgent but not immediately life-threatening: a fouled propeller in a navigable channel, a non-critical medical issue, an engine failure with no immediate grounding risk, lost overboard equipment that needs reporting.

The protocol on Channel 16:

“Pan-pan, pan-pan, pan-pan. All stations, all stations, all stations. This is sailing vessel Wanderer, Wanderer, Wanderer. Position: 47 degrees 38 minutes north, 122 degrees 24 minutes west. Engine failure, drifting toward Bainbridge Island shoreline. Three persons aboard. Request assistance from any vessel in the area. Over.”

The format: pan-pan three times → all stations three times → vessel name three times → position → nature of situation → assistance requested → over.

The USCG will respond. So will any nearby commercial or recreational vessel that hears the call.

Distress calls — Mayday

For life-threatening emergencies: a fire, a sinking, a medical emergency, an MOB the boat cannot recover unaided. The format is fixed; deviate from it and the dispatcher loses time.

“Mayday, mayday, mayday. This is sailing vessel Wanderer, Wanderer, Wanderer. Position: 47 degrees 38 minutes north, 122 degrees 24 minutes west, two miles east of Bainbridge Island. We have a fire in the engine compartment, three persons aboard, sailing vessel forty feet, request immediate assistance. Mayday Wanderer. Over.”

The format: Mayday three times → vessel name three times → position → nature of distress → number of persons aboard → vessel description → assistance requested → close with vessel name. Pause. If no response in thirty seconds, repeat.

If you have time before the Mayday, press the DSC distress button. Then transmit voice. Both.

If you cannot transmit a complete Mayday — fire spreading, sinking faster than expected — at least say Mayday and your position. Position is the single piece of information that determines whether a SAR asset can find you. Everything else can be inferred or asked. Position cannot.

What the Coast Guard hears, and what they do

Sector Puget Sound (Seattle), Sector Columbia River (Astoria), and Sector North Bend (Oregon Coast) operate 24/7 listening watches on Channels 16 and 70. A Mayday triggers an immediate response: a 47-foot Motor Lifeboat from the nearest small-boat station typically launches within 15 minutes; an HH-65 Dolphin or HH-60 Jayhawk helicopter from Air Station Astoria or Air Station Port Angeles can be airborne in roughly 30 minutes; a Coast Guard cutter in the area is diverted.

In populated coastal areas — Puget Sound, the Strait of Juan de Fuca, the Columbia River estuary — USCG response is typically within an hour and often within 30 minutes. Remote outer-coast waters — the outer Olympic Peninsula, the Oregon coast between Astoria and Newport, the open Pacific beyond the small-boat stations’ range — may take longer; in those areas an HH-60 helicopter from Air Station Astoria or a long-range cutter is the realistic responder, and the timeline scales with distance. The cruiser’s job in either case is the same: keep transmitting, keep position updates flowing, stay alive long enough to be found.

Pacific Northwest specifics

Puget Sound ferries. The Washington State Ferry fleet — Walla Walla, Tacoma, Wenatchee, the Jumbo Mark IIs — operates on Channels 13 (bridge-to-bridge) and 16. When transiting near a ferry lane, monitor 13 in addition to 16. Ferry operators are professional, predictable, and will hail you on 13 if you are in their way. They expect a response.

Strait of Juan de Fuca traffic separation scheme. The TSS runs from the Pacific entrance east to Port Angeles and on to the Vancouver and Seattle approaches. Recreational vessels under sail or power may transit but must do so at right angles to the lanes. Monitor Channel 16 and switch to Channel 13 when crossing the TSS. Commercial traffic in the lanes — bulk carriers, tankers, container ships — will not stop for you.

Commercial fishing. PNW commercial fishing fleets coordinate heavily on Channels 9 and 12. During salmon and crab seasons these channels are busy. Recreational vessels keep clear of fishing-coordination chatter on those channels and use Channel 9 sparingly.

Locks and tidal gates. The Hiram M. Chittenden Locks (Ballard) operate on Channel 13. Hail the lockmaster on approach.

Canadian Pacific waters. Channel 16 is universal. Beyond that, Canadian recreational coastal stations use Channels 6 (intership safety), 22A (US/Canadian harbour bridge-to-bridge), 73 (Canadian working channel). The CCG monitors Channel 16 from Comox, Tofino, and Victoria.

NOAA weather. Continuous broadcasts on WX-1 (162.40 MHz) for outer coastal forecasts; WX-3 (162.45 MHz) for Puget Sound and the Strait of Juan de Fuca. Check the weather before departure. Re-check at every condition change.

Equipment standard

A working PNW VHF setup:

• A fixed VHF transceiver, 25-watt, with DSC and a registered MMSI, wired to the GPS
• An external antenna, mounted at the masthead on sailboats or as high as practical on powerboats
• A handheld VHF (Standard Horizon HX870, Icom IC-M37) in the grab bag — DSC and built-in GPS, used as backup if the main set fails
• A copy of the channel list near the helm
• A pencilled note of the boat’s MMSI and call sign at the helm

The fixed VHF is the primary. The handheld is what survives the dismasting, the engine fire, the abandon-ship.

Common mistakes

Treating Channel 16 as a working channel. It is for distress, safety, and initial contact. Conversation moves to a working channel. The cruiser who chats on 16 is the cruiser who will not be heard on 16 when someone else needs to.

Transmitting before listening. Press the squelch override briefly to hear the static; if the static is broken by speech, the channel is in use. Wait. Then call.

Failing to register the DSC MMSI. An MMSI assigned but not registered to the boat means a DSC distress call gives the Coast Guard a number that does not match a vessel. They will respond — but the response is slower because they cannot pre-load any information. Register through BoatUS (free for US recreational vessels) or directly with the FCC.

Skipping the position. In a real Mayday, the cruiser may forget to give the position. The Coast Guard’s first request after acknowledging the call is “vessel in distress, what is your position?” — give it first to save the round-trip. Practice saying your latitude and longitude out loud, twice, before you leave the dock.

The rule

Channel 16 is the channel that saves your life. Keep the radio on, the volume up, the squelch correct, and the DSC button uncovered.

The radio that is off when the call comes in is no use. The Mayday that is not transmitted with a position is half a Mayday.

Related: Marine Safety Equipment · Man Overboard · Cold Water Survival · Reading Marine Weather