What action would you take if you encounter a head on situation?

Neither power-driven vessel A nor power-driven vessel B gives way or stands on in a head-on encounter. Therefore, some communication is needed between vessels A and B.

The most common response in a head-on meeting between power-driven vessels is to signal an intention to pass port-to-port. This action is initiated by one of the vessels sounding one short blast.

In short, vessel A must blow one short blast, indicating its intention to pass port-to-port, and then alters its course to starboard. Vessel B must return one short blast—to indicate agreement and understanding—and alter its course to starboard, thereby, leaving room on each vessel's port side for passing.

Starboard-to-Starboard

If it is not possible to pass port-to-port due to an obstruction or shoreline, a starboard-to-starboard pass should be signaled with two short blasts.

In short, vessel A must blow two short blasts, indicating its intention to pass starboard-to-starboard, and alter its course to port. Vessel B must return two short blasts to indicate agreement and understanding and alter its course to port, thereby, leaving room on each vessel's starboard side for passing.

10/33

1. Home
2. Driving, boating and transport
3. Waterways safety and rules
4. Rules
5. Giving way

This page is managed by

Transport for NSW

Your rating will help us improve the website.

a. When two power-driven vessels are meeting on reciprocal or nearly reciprocal courses so as to involve risk of collision each shall alter her course to starboard so that each shall pass on the port side of the other.

Meaning: It is a clear instruction when the vessels are head on perfectly, the thing to remember is that when the vessels are nearly on reciprocal courses, then to the vessels are asked to alter course to starboard.

A nearly reciprocal course would deem that the vessels would be passing very close to each other, and the situation can become a close quarter situation when the ships are quite close.

b. Such a situation shall be deemed to exist when a vessel sees the other ahead or nearly ahead and by night she could see the masthead lights of the other in a line or nearly in a line and/or both sidelights and by day she observes the corresponding aspect of the other vessel.

Meaning: The Rule is very clear about the sightings and has explained what is to be termed as Head On, a number of cases have come about when this basic Rule is forgotten and the
watch keeper relies on the ARPA to give him the CPA.
The Radar and the ARPA are assistances for the watch keeper and do not replace the Rule instructions.

c. When a vessel is in any doubt as to whether such a situation exists she shall assume that it does exist and act accordingly.

Meaning: Again the same word ‘Doubt’. So even if the CPA as per the ARPA is marginal

This project has been funded with support from the European Commission. This publication [communication] reflects the views only of the author, and the Commission cannot be held responsible for any use which may be made of the information contained therein.