What should two power driven vessels do when they meet head on?

The waterways are spaces where the lanes are not marked, but there is still a right place to be.

Boating Rules

There are rules that apply to boats on the water, just like cars on the road. It's important to learn these rules to avoid collision and maintain your safety and the safety of others on the water. This sea yarn is a fun and easy way to help you remember the rules of the road at sea.

Rules to remember when two vessels meet

When two power vessels are approaching head on,both vessels should alter course to starboard to pass port-side to port-side.
When two power-driven vessels are in crossing situation on a collision course, give way to the vessel to starboard (right). The give way vessel must take early and obvious action to avoid a collision by either stopping or altering course to starboard.
If the give way vessel has another power-driven vessel from the Port (left) which does not take obvious action to give way, or alter course to starboard, then the Skipper of give-way (stand on) vessel must take evasive action by either stopping, or again, altering course to starboard.
Every vessel (power or sail) that is overtaking must keep well clear of the over taking vessel. You are overtaking if you are approaching another vessel anywhere in a 135 degree sector at its stern.

Channels and harbours

All vessels must keep to the starboard (right) side of any channel.
Inside a harbour (normally shown on the pilotage limit on the chart) you must keep out of the way of any ship over 500 tons. (which is about 50 metres in length)
Do not create a wake which causes unnecessary danger to other vessels or people.
You must not anchor in a channel.
All small craft must keep out of the way of larger vessels which are restricted by their draft to maintain passage and steering within the channel.

When power meets power

You must give way to another vessel on your starboard. (right)
If you meet head on, both vessels must turn to starboard. (right)

When power meets sail

Power gives way to sail unless the sailing vessel is overtaking.
Sailing vessels should avoid sailing in a narrow channel. They have to give way to power-driven vessels restricted in their ability to manoeuvre in the channel.

When sail meets sail

The vessel which has the wind on its starboard (right) side has the right of way. The vessel which has the wind on its port (left) side must give way.
When both boats have the wind on the same side the windward (upwind) boat has to give way.

When things go wrong

If the give way vessel does not appear to be giving way, the stand on vessel must take evasive action and should turn to starboard (right). Do not alter course to port, it could place you into the path of the give way vessel.

Use the concept of the "Imaginary Line" to help you determine whether you are travelling upstream or downstream on a river or when entering a port or harbour so that you pass channel marks on the correct side.

When two power driven vessels are approaching head-on or nearly so, either vessel shall indicate its intent which the other vessel shall answer promptly. In a meeting situation, neither vessel is the stand-on vessel.

It is generally accepted that you should alter course to starboard and pass port-to-port. The accompanying sound signal is one short blast.

If you cannot pass port-to-port due to an obstruction or other vessels, you should sound two short blasts to indicate your intention to pass starboard-to-starboard. Make sure the other vessel understands your intent before proceeding. The other vessel should return your two-short-blast signal.

Overtaking an other vessel

When two vessels are moving in the same direction, and the astern vessel wishes to pass, it must initiate the signal to pass as shown in the diagram. The vessel passing is the give-way vessel and should keep out of the way of the vessel being passed. The vessel being passed is the stand-on vessel and must maintain its course and speed. If the stand-on vessel realizes that the course intended by the give-way vessel is not safe, it should sound the danger or doubt signal.

A vessel is deemed to be overtaking when the vessel is approaching the vessel ahead in a direction of 22.5 degrees abaft her beam. At night you would only be able to see the stern light of the vessel being overtaken. You would not be able to see either sidelight.

If you are overtaking a vessel, remember that you are the give-way vessel until well past, and safely clear of, the passed vessel. Do not cut in front of, impede or endanger another vessel.

"I intend to pass you on your port side" - 2 short blasts (1 sec.)

"Agreement" - 2 short blasts (1 sec.)

"I intend to pass you on your starboard side" - 1 short blast (1 sec.)

"Agreement" - 1 short blast (1 sec.)

If the sailboat is overtaking a powerboat, the powerboat is the stand-on vessel and the sailboat must give way.

Note that the following illustrations are not drawn to scale. The vessels are shown closer to each other than they should be when actually encountering another vessel on the water.

Meeting Head-On: The power-driven vessel is the give-way vessel. The sailing vessel is the stand-on vessel.

Paths That Cross: The power-driven vessel is the give-way vessel. The sailing vessel is the stand-on vessel.

Overtaking: The vessel that is overtaking another vessel is the give-way vessel, regardless of whether it is a sailing vessel or a power-driven vessel. The vessel being overtaken is always the stand-on vessel.

If operating a power-driven vessel, you must always give way to a sailing vessel unless the sailing vessel is overtaking your vessel.

The actions you must take when encountering another vessel are found in the Collision Regulations.

Note that the following illustrations are not drawn to scale. The vessels are shown closer to each other than they should be when actually encountering another vessel on the water.

Meeting Head-On: Neither vessel is the stand-on vessel. Both vessels should turn to starboard (the right).

Paths That Cross: The vessel on the operator’s port (left) is the give-way vessel. The vessel on the operator’s starboard (right) is the stand-on vessel.

Overtaking: The vessel that is overtaking another vessel is the give-way vessel. The vessel being overtaken is the stand-on vessel.

give-way vessel The vessel that is required to take early and substantial action to keep out of the way of other vessels by stopping, slowing down, or changing course stand-on vessel The vessel that must maintain its course and speed unless it becomes apparent that the give-way vessel is not taking appropriate action; if you must take action, do not turn toward the give-way vessel or cross in front of it