Fog Signal Underway Making Way

When visibility at sea becomes limited due to fog, mist, or heavy rain, it becomes extremely important for ships and boats to communicate their movements clearly. One of the most essential ways to do this is through sound signals, known as fog signals. The term fog signal underway making way refers to the specific sound that a vessel must make when it is moving through the water but visibility is poor. This practice is a key part of maritime safety and helps prevent collisions between vessels in low-visibility conditions.

Understanding Fog Signals

Fog signals are a vital part of the International Regulations for Preventing Collisions at Sea (COLREGs). These signals are standardized sound signals that vessels use to announce their status and intentions when visual cues, like lights or flags, cannot be seen. Each signal indicates whether the vessel is moving, stopped, anchored, or restricted in movement. The type and timing of each signal help nearby vessels determine how to navigate safely around one another.

These signals are typically produced using a ship’s whistle, horn, or bell, and their sound must be loud enough to travel through dense fog. Because fog can distort sound, it is crucial for mariners to be familiar with the rhythm and meaning of each type of fog signal.

Meaning of Underway Making Way

The phrase underway making way has a specific meaning in maritime terminology. A vessel is considered underway when it is not at anchor, not made fast to the shore, and not aground. However, being underway does not always mean that the vessel is moving through the water. Making way means that the vessel is actually in motion, propelled either by wind, engines, or other means.

Therefore, a ship that is underway making way is one that is actively moving. This distinction matters because the required fog signal depends on whether the vessel is moving or stationary. The sound signals communicate this status to other vessels nearby, allowing them to react appropriately to avoid danger.

Fog Signal for a Vessel Underway Making Way

According to the COLREGs Rule 35, when a power-driven vessel is underway making way in fog or restricted visibility, it must sound a prolonged blast on its whistle at intervals of no more than two minutes. This signal helps alert other vessels that it is moving through the water.

Power-Driven Vessel Making Way

The signal pattern for a power-driven vessel that is underway and making way is

• One prolonged blast every two minutes.

A prolonged blast is defined as a sound lasting between four and six seconds. The sound must be powerful enough to be heard at least one to two nautical miles away, depending on conditions and vessel size.

Power-Driven Vessel Underway but Not Making Way

If the same vessel is underway but not moving (for example, if it has stopped in the water due to engine failure or other reasons), the correct fog signal is different. It must sound

• Two prolonged blasts every two minutes.

This tells nearby vessels that it is present in the water but not moving forward, so they must maneuver carefully around it.

Other Vessels and Their Fog Signals

Different types of vessels have specific fog signals, depending on their function or restriction in maneuverability. Understanding these signals is crucial for any mariner navigating in fog or mist. Here are some examples

• Vessel not under command, restricted in maneuverability, or constrained by draftOne prolonged blast followed by two short blasts every two minutes.
• Sailing vesselOne prolonged blast followed by two short blasts every two minutes.
• Vessel at anchorRapid ringing of a bell for about five seconds every minute.
• Vessel agroundBell signal as for a vessel at anchor, followed by three distinct strikes of the bell before and after the ringing.

By learning these patterns, seafarers can interpret the presence and movement of other ships even when they cannot see them.

Importance of Fog Signals for Maritime Safety

Fog signals play a crucial role in preventing collisions and ensuring the safety of all vessels navigating in low-visibility conditions. The ocean can be unpredictable, and when sightlines are obscured by fog or heavy weather, the ability to rely on sound becomes life-saving. These signals provide a consistent and reliable method for vessels to announce their presence and movement to others in the vicinity.

In busy shipping lanes, where multiple vessels may be moving in close proximity, proper use of fog signals helps maintain safe distances and clear communication. Even small recreational boats are expected to use appropriate signals when traveling in foggy conditions.

How Mariners Use Fog Signals in Practice

In practice, the captain or officer of the watch is responsible for ensuring that the correct fog signal is sounded at proper intervals. The ship’s automatic whistle or horn system may be used, or manual signals can be given if necessary. When hearing a fog signal, the crew must take immediate action to determine the position, course, and speed of the other vessel using radar, sound direction, and other navigational instruments.

Modern technology, such as Automatic Identification Systems (AIS) and radar, greatly assists in identifying vessels in fog, but the fog signal remains an essential safety measure because it provides an audible warning that does not depend on electronic systems.

Differences Between Sound Signals and Fog Signals

Although fog signals are a type of sound signal, there are some key differences between general sound signals and those specifically used in restricted visibility

• Sound SignalsUsed during normal visibility to indicate maneuvers such as turning or overtaking. For example, one short blast means I am altering my course to starboard.
• Fog SignalsUsed when visibility is reduced to announce a vessel’s presence and movement, not its intentions.

This distinction is important because the meaning of the sounds changes depending on the situation. In fog, the goal is not to signal a maneuver but to let others know that you are there and moving.

Examples of Underway Making Way Situations

To understand this concept better, consider the following examples

• A cargo ship traveling through dense morning fog in the English Channel sounds one prolonged blast every two minutes to indicate it is moving forward.
• A fishing boat motoring slowly near the coast in misty conditions must also sound one prolonged blast at the same interval.
• A ferry that has stopped mid-channel to adjust its course is still underway but not making way, so it gives two prolonged blasts.

Each of these situations demonstrates the practical application of fog signals in real maritime operations.

Training and Compliance

All mariners, from small-boat operators to large vessel captains, are required to understand and comply with fog signal regulations. Training programs and maritime schools teach the proper use and interpretation of these signals as part of navigation safety courses. Non-compliance can result in accidents, legal penalties, and loss of certification for professional mariners.

Authorities such as the International Maritime Organization (IMO) and national coast guards emphasize continuous training and periodic drills to ensure that all personnel remain proficient in using sound signals under various conditions.

Knowing when and how to use a fog signal underway making way is a fundamental aspect of maritime navigation and safety. It ensures that vessels can communicate effectively even when visibility drops to near zero. A single prolonged blast every two minutes from a moving vessel serves as a universal alert to others, reducing the risk of collision and ensuring smoother operations on the water. Whether navigating a massive cargo ship or a small fishing boat, respecting these rules helps maintain order and safety at sea. The fog signal system, though centuries old, remains one of the most reliable forms of maritime communication in existence today.