Chapter 2 · Lesson 4Talking lesson with graphics · about 5 minutes
COLREGS: start seeing the situation
Recognise basic meeting situations, report developing risk and understand why a junior lookout never turns a simplified rule into a navigation decision.
Video coming soon
COLREGS: start seeing the situation
In the video
- Overtaking, head-on and crossing: the basic shapes
- Why a radar-only contact is a different context
- A steady bearing with closing range, and reporting the trend
From the captain
Before you start
A one-line COLREGS memory trick is useful until somebody treats it as the whole rule. Your job at this stage is to recognise what may be developing and tell the officer early.
By the end of this lesson
Recognise an emerging encounter and report evidence without substituting a slogan for the full rules.
See it
See it for yourself
Watch the bearing and the range
A bearing line every two minutes. Parallel lines and a shrinking range: report it.
5/5Report the bearing, the estimated range and what is changing. The officer considers radar, visual information, vessel constraints and the full COLREGS.
Illustration · example readouts, not limits · own ship does not alter here: no avoidance manoeuvre is shown · the officer applies the full COLREGS
What to look for
Context precedes the encounter name
Establish whether vessels are in sight and what can actually be observed. A radar-only contact in restricted visibility must not be assigned a visual crossing give-way/stand-on label from a simple sketch.
Report the trend
Repeated bearing and range information can be more useful than a confident encounter label. Do not withhold a report because the bearing changes slightly; the OOW assesses the full risk.
The lesson
The lesson
- 01
Recognise the basic shapes
Begin with the observation: whether vessels are in sight, their aspect and what is changing. Learn the overtaking, head-on and crossing shapes alongside the complete International Rules 11–18. Do not label a radar-only contact in restricted visibility as a visual crossing give-way or stand-on situation; Rule 19 has a different application. Your role is to report the evidence while the officer assesses the applicable rules.
Three basic shapes, and when the names apply
Learn the shapes. Then switch to radar only: the Rules 13–15 labels do not apply, and Rule 19 has a different application.
In sight of one another: learn the overtaking, head-on and crossing shapes alongside the complete International Rules 11–18. Describe what you see and what is changing, and report it. The officer assesses the applicable rules.
Illustration · no avoidance track or give-way label · the complete International Rules 11–19 govern · the officer decides
- 02
Watch the bearing and range
A contact that remains on a similar bearing while getting closer may indicate risk of collision. Report the bearing, estimated range and what is changing. Do not wait for certainty and do not suggest a manoeuvre unless asked within your role. The officer considers radar, visual information, vessel constraints and the full COLREGS.
- 03
Learn from the watch you are already standing
When the workload permits, ask the officer to explain a situation after it has been dealt with. First complete your lookout duties; curiosity is excellent, but not while the contact is two miles away and the officer is busy. Keep a reference and build the rules properly over time.
Where it goes wrong
A lookout sees a sailing yacht and assumes ‘sail always has right of way’, so they delay reporting it. That slogan ignores the actual circumstances and the full responsibilities between vessels. The lookout's safe job was to report the contact early, not decide that one vessel could be ignored.
Your call
What would you do?
Pick one, then read the feedback on all three.
The situation
In restricted visibility, a contact appears on radar but cannot be seen. Another learner calls it a normal crossing situation and says you are stand-on.
Take it aboard
Describe before naming
Do this during your induction or first weeks, with the person responsible for your work.
Desk exercise
Use three simple tabletop encounters and one radar-only written scenario.
- 01State visibility and whether the vessel is in sight.
- 02Describe direction and change.
- 03Name what remains unknown.
- 04Practise the report you would give the OOW.
What a useful result looks like
- You state the observation basis.
- No universal right-of-way slogan is used.
- The navigation decision remains with the OOW.
Stop: No exercise answer is a helm order or substitute for the complete rules.
Deckhand Foundation · Job card
Encounter observation
From the lesson: COLREGS: start seeing the situation
- Visibility and in-sight status known.
- Contact description and movement reported.
- Bearing and range trends passed with uncertainty.
- Full rule context referred to the OOW.
Observed facts
Unknowns
Report
Your vessel's procedures and senior crew come first. Nothing on this card is stored.
Quick check
Four decisions, then move on
This check confirms the principle. Your vessel's own induction still comes first.