4.1 Bridge-to-Bridge Operations (Key Topic 7)

4.1 Bridge-to-Bridge Operations (Key Topic 7)

Element 1 Key Topic 7 tests how a Marine Radio Operator Permit holder runs the Vessel Bridge-to-Bridge Radiotelephone Act station: where the set lives, what traffic it may carry, how much power it may radiate on Channel 13, and how the ship identifies. OpenExamPrep teaches those operating facts from 47 CFR Part 80, 33 CFR Part 26, and U.S. Coast Guard Navigation Center (NavCen) radio information for boaters so you can stand the watch, not merely recognize a call-sign format.

Quick operating picture: A bridge-to-bridge station is a VHF radiotelephone on the navigational bridge or main control station used only for navigational communications. In most U.S. waters that means Channel 13 at 1 watt. You may identify by ship name. Raise power only for an emergency, a called vessel that will not answer, or a blind situation such as rounding a bend.

Vessel Traffic Service

The U.S. Coast Guard operates Vessel Traffic Service (VTS) in certain designated water areas. NavCen describes VTS as a service implemented to improve the safety and efficiency of vessel traffic and to protect the environment. The Element 1 pool states the same mission in exam language: prevent ship collisions, groundings, and environmental harm.

VTS is not a public-correspondence marine operator, not a NOAA weather radio, and not an internal ship telephone. A Vessel Traffic Center talks to participating ships on designated VTS frequencies and uses VHF, Automatic Identification System (AIS), radar, and cameras to keep traffic orderly. Participating vessels provide transit plans (NavCen calls these Sailing Plan Reports). Inside a VTS area, 33 CFR 26.04 makes the designated VTS frequency an additional designated frequency that required vessels must monitor, on top of the bridge-to-bridge channel.

Do not confuse VTS with Channel 16 distress. VTS keeps ships from hitting each other, the bottom, or a tank farm. Channel 16 is still where a MAYDAY belongs unless a specific watchkeeping exception (Key Topic 3 / 47 CFR 80.148) applies because the vessel is already guarding both Channel 13 and the VTS channel.

Channel 13 numbers you will actually use

NavCen’s U.S. VHF channel table lists Channel 13 as 156.650 MHz, intership navigation safety (bridge-to-bridge). Ships greater than 20 meters in length maintain a listening watch on this channel in U.S. waters. Channel 67 (156.375 MHz) is the bridge-to-bridge frequency on the lower Mississippi River. NavCen tells boaters to use Channel 13 to contact a ship when there is danger of collision. Improper use can draw an FCC fine; the operating cure is brevity and navigation-only content, not a longer speech.

33 CFR 26.04 forbids using the designated frequency to transmit any information other than information necessary for the safe navigation of vessels or necessary tests. You may still use that frequency to communicate with shore stations to obtain or furnish information necessary for safe navigation. That shore clause does not turn Channel 13 into a marine-operator working pair.

What a Bridge-to-Bridge Station Is

A bridge-to-bridge station is a VHF radio station located on a ship’s navigational bridge or main control station that is used only for navigational communications. That sentence is the whole job description. It is not an internal sound-powered phone linking the wheelhouse to the radio room. It is not a portable “roving” ship station you carry from hull to hull to avoid a license application. It is not an inland coastal public-correspondence office serving ships in U.S. waters.

The primary purpose of bridge-to-bridge communications is navigational communications: meeting, crossing, overtaking, intentions, position, course, speed, and any other information necessary for the safe navigation of vessels. Captain’s orders from the bridge to the engine room belong on the ship’s internal system. Search-and-rescue may use VHF, but Channel 13 is not reserved for SAR-only calls. Short-range radios aboard ship include many circuits; only the wheelhouse VHF used for navigation is the bridge-to-bridge station.

Spoken format on the designated frequency

47 CFR 80.331 tells you how the exchange should sound. A typical blind broadcast: 'This is the (name of vessel). My position is (readily identifiable position, course and speed) about to (contemplated action). Out.' A directed call: name the other vessel by a readily identifiable position, identify your ship and position, state the plan, and end with 'Over.' The called vessel answers with names, 'Received your call,' and its intentions. Communications terminate when each ship is satisfied that the other no longer poses a threat to its safety, and they end with 'Out.'

Keep the geography concrete: buoy, bend, bridge, or mile marker beats a vague 'we are out here.' The other watchstander is looking out a window, not reading your log.

Power on Channel 13: 1 Watt Unless an Exception Applies

Keep the bridge-to-bridge transmitter at 1 watt for ordinary navigational talk. Higher power lights up every receiver in range and wrecks the close-quarters channel you need for passing arrangements.

47 CFR 80.331(c) limits use of power greater than 1 watt in a bridge-to-bridge station to three situations:

1. Emergency.
2. Failure of the vessel being called to respond to a second call at low power.
3. A broadcast call in a blind situation, for example rounding a bend in a river.

How Element 1 asks the power question

The live exam can phrase the same rule two ways. Learn both; they are not tricks so much as two slices of 80.331(c).

• High power on Channel 13 is legal for failure of the vessel being called to respond, in a blind situation such as rounding a bend, or during an emergency — all of these.
• A bridge-to-bridge transmission may be more than 1 watt when broadcasting a distress message and rounding a bend in a river or traveling in a blind spot. That combined wording is a tested pairing: distress plus a geography problem that hides you from the other ship. It is not 'call the Coast Guard on Channel 13 for a radio check,' and it is not high power for distress or a bend as two unrelated excuses in that particular item — the tested choice joins them.

Do not raise power merely because you want the Coast Guard, merely because you are carrying cargo, or merely because another ship is far away. Try 1 watt first. If the called vessel does not answer a second low-power call, 80.331 permits higher power. If you cannot see around a bend, a blind broadcast at higher power is the tool the rule contemplates. If the situation is an emergency — including distress — higher power is permitted.

Identification on Channel 13

A ship station using VHF bridge-to-bridge Channel 13 may be identified by the name of the ship in lieu of the call sign. 47 CFR 80.102(c) states that ship stations transmitting on any authorized VHF bridge-to-bridge channel may be identified by the name of the ship in lieu of the call sign. 80.102(d) likewise lets a ship in a VTS system, or on a waterway under a U.S. Government or foreign authority, identify by ship name when talking to that authority, or as that authority directs.

You still need a call sign for other radiotelephone work. Channel 13 is the exception Key Topic 7 cares about: the ship name is enough. You do not add 'and country of origin' as a Channel 13 requirement. You are not excused from identification merely because you are within 100 miles of shore. Private coast stations at drawbridges transmitting on 156.650 MHz may identify by the name of the bridge (80.102(b)). Radar transmitters must not send station identification at all (80.104) — that is a different station.

Putting the Watch Together

Stand the Channel 13 watch from the place the ship is navigated. Under 47 CFR 80.309, the master or the person directing movement of the vessel (or a designee) keeps the Bridge-to-Bridge Act watch; other duties are allowed only if they do not interfere with the watch. Sequential scanning by itself does not satisfy a required dual watch on Channel 13 and a VTS channel — that is why many bridges fit two receivers or a handheld plus a fixed set.

Channel 16 remains the distress, safety, and calling frequency (156.800 MHz). Bridge-to-bridge does not replace MAYDAY procedures on NavCen’s Channel 16 voice format. When a vessel is subject to the Bridge-to-Bridge Act and is participating in a VTS system, 47 CFR 80.148 lets the compulsory Channel 16 watch drop only if the vessel monitors both the bridge-to-bridge frequency and the separately assigned VTS frequency. That exception is watchkeeping detail from Key Topic 3; the operating point here is that VTS and Channel 13 are navigation-safety circuits, while Channel 16 is still where distress belongs unless that specific exception applies.

USCG NavCen’s radio information for boaters still gives the classic voice-calling habit that keeps Channel 16 short: name the called station, identify yourself, then move to a working channel. Use the same brevity on Channel 13. Say who you are, where you are, and what you intend, then get off the air.

Key Topic 7 in practice: know that VTS is a Coast Guard collision-and-grounding service, know that bridge-to-bridge is VHF on the navigational bridge for navigational communications only, know the 1-watt rule and every high-power exception the pool uses, and know you may identify by ship name on Channel 13.