Observe and identify
Developing level, about 2 min. IALA worldwide marks.
The situation
A navigation light lies ahead. Start playback and watch at least one complete cycle. Its period is an illustrative charted example; identify the combination of colour and rhythm.
Which mark matches the light you observe?
- Special mark
- Port-hand mark · Region A
- Starboard-hand mark · Region A
Answers and explanations
Lookout: Yellow body, yellow X and a yellow light when fitted.
The sound answer
Special mark
Yellow with a yellow X topmark when fitted. Indicates an area or feature described on the chart. Its yellow light avoids characters reserved for cardinal, isolated-danger and safe-water marks; colour alone does not tell you which side to pass.
Why the other options fall short
Port-hand mark · Region A
Red can-shaped lateral mark. In the conventional direction of buoyage, leave it to port. In the opposite direction, leave it to starboard. Read the charted buoyage direction rather than assuming every passage is inward. Here the observed cue identifies special mark. Yellow with a yellow X topmark when fitted. Indicates an area or feature described on the chart. Its yellow light avoids characters reserved for cardinal, isolated-danger and safe-water marks; colour alone does not tell you which side to pass.
Starboard-hand mark · Region A
Green conical lateral mark. In the conventional direction of buoyage, leave it to starboard; travelling against that direction reverses the side of your vessel on which you leave it. Here the observed cue identifies special mark. Yellow with a yellow X topmark when fitted. Indicates an area or feature described on the chart. Its yellow light avoids characters reserved for cardinal, isolated-danger and safe-water marks; colour alone does not tell you which side to pass.
Special marks
Yellow with a yellow X topmark when fitted. Indicates an area or feature described on the chart. Its yellow light avoids characters reserved for cardinal, isolated-danger and safe-water marks; colour alone does not tell you which side to pass.