IALACOLREG
8

Action to Avoid Collision

Any action to avoid collision shall be positive, made in ample time, and with due regard to good seamanship.

Rule 8 prescribes how avoiding action should be taken. Any action shall be positive, made in ample time and with due regard to the observance of good seamanship.

a
Avoiding action shall be taken in accordance with the Rules.
b
Alterations of course and/or speed should, if circumstances admit, be large enough to be readily apparent to another vessel visually or by radar. A succession of small alterations should be avoided.
c
If there is sufficient sea room, alteration of course alone may be the most effective action, provided it is substantial, made in good time and does not create another close-quarters situation.
d
The resulting passing distance must be safe.
e
If necessary to avoid collision or allow more time for assessment, a vessel shall slacken speed, stop, or take all way off by stopping or reversing propulsion.
f
When using radar, check the effectiveness of the avoiding action until the other vessel is finally past and clear.

STCW Bridge Watch Lens

1

Decide applicability before manoeuvring: Rules 4-10 apply in any visibility, Rules 11-18 only when vessels are in sight, and Rule 19 governs radar-only encounters in restricted visibility.

2

Build the traffic picture with sight, hearing, radar/ARPA and chart context. Do not let AIS or one isolated bearing replace systematic observation.

3

After manoeuvring, keep monitoring bearing, range, CPA/TCPA and passing distance until the other vessel is finally past and clear.

Exam Focus

1

Start every scenario by classifying the encounter: overtaking, head-on, crossing, narrow channel, traffic separation, or restricted visibility.

2

If two rules seem to conflict, check the order carefully: overtaking duties still apply, and Rule 2 still requires ordinary seamanship.

3

Steady or nearly steady bearing is the classic trigger, but close range, a large vessel or a tow can still mean risk even when bearing change seems small.

Key Takeaways

1

Take early, positive action that the other vessel can actually see or detect

2

Avoiding action should create a safe passing distance, not merely miss by chance

3

Do not be afraid to reduce speed, stop or reverse if that is the safest action

4

After manoeuvring, verify that the action is working

Common Mistakes

Making several small alterations that are hard for the other vessel to interpret

Waiting until the last moment and then blaming the other ship

Failing to monitor whether the manoeuvre has really opened the situation

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