Misuse of VHF radio communications and the COLREGS

A reporter alerts CHIRP to the increasing misuse of VHF communications for collision avoidance.

What did the reporters tell us?

A watch keeper maintains a VHF radio watch. He writes: “I notice that there is an increasing amount of (mis-)communication between vessels concerning collision avoidance… (sometimes) there is a continuous chatter of vessels making agreements”. He asks ‘what has happened to just sticking to the COLREGS’. He notes that there has been a huge increase in these “collision avoidance arrangements” over the last 10 years.

The lessons to be learnt

The reporter makes an important point; it recurs repeatedly in the reports received by CHIRP.

The COLREGS are based on the tried and tested practice of decades. They exist to make the correct actions clear, and were originally developed long before bridge-to-bridge voice communications became    available.

They are thus unambiguous. It is the responsibility of all bridge watch keepers to know how to apply them instinctively, on the basis of observation primarily by sight and radar. They work effectively when ships in an interaction obey them; they also specifically address circumstances where one ship does not.

Of course VHF radio is used for the purpose of traffic management, for example in traffic separation schemes (TSSs). There can also be circumstances where – for some exceptional reason – VHF radio exchanges can assist deconfliction. If they are so used, neither ship should rely on the other to take the action ‘arranged’ until this is independently verified; indeed it should be assumed that the action has not been taken until it is seen to be happening. The greatest risk attaches to ‘arrangements’ which are contrary to the COLREGS; these are hazardous.

Further risks of language confusion, mis-identification between the communicating vessels, distraction of other ships in the area and distraction from the officer of the watch (OOW)’s primary tasks all add risk to the use of VHF in collision avoidance. It is true that AIS has made identification of vessels easier, but at busy moments – especially in heavy shipping situations – mistakes can still be made. It can also be particularly tempting to use VHF when, as the stand-on vessel, we encounter give-way ships not taking the right action. However the COLREGS make quite clear what to do in this situation: ‘take action to avoid’.

Finally the ‘VHF in collision avoidance’ habit can also erode the plain and absolute authority of the COLREGs in the minds of OsOW, and thus their instinctive and confident application of them. This represents a serious longer term threat to safety at sea.

CHIRP Suggests

Doubt = danger. VHF communication in collision avoidance can increase doubt, misunderstanding, delay and distraction. Use it only in exceptional situations, and then with utmost caution. Apply the COLREGS, know them instinctively, and take early and substantial action in accordance with them when the circumstances of the case require.