Observe and identify
Developing level, about 2 min. International COLREGs / IRPCS.
The situation
A vessel ahead is showing a daytime shape. Inspect the shape and its vertical arrangement with the binoculars. The vessel’s name and status are withheld until your answer.
Which operation or status does this daytime signal indicate?
- Tow exceeding 200 m
- Constrained by draught
- At anchor
Answers and explanations
Lookout: A diamond indicates a tow exceeding 200 m measured from the stern of the towing vessel to the after end of the tow. It is displayed by the towing vessel and the towed vessel or object where prescribed; a long tow is not automatically a restricted-manoeuvrability operation.
The sound answer
Tow exceeding 200 m
A diamond indicates a tow exceeding 200 m measured from the stern of the towing vessel to the after end of the tow. It is displayed by the towing vessel and the towed vessel or object where prescribed; a long tow is not automatically a restricted-manoeuvrability operation.
Why the other options fall short
Constrained by draught
Constrained by draught uses cylinder. The displayed signal here indicates tow exceeding 200 m. A diamond indicates a tow exceeding 200 m measured from the stern of the towing vessel to the after end of the tow. It is displayed by the towing vessel and the towed vessel or object where prescribed; a long tow is not automatically a restricted-manoeuvrability operation.
At anchor
At anchor uses ball. The displayed signal here indicates tow exceeding 200 m. A diamond indicates a tow exceeding 200 m measured from the stern of the towing vessel to the after end of the tow. It is displayed by the towing vessel and the towed vessel or object where prescribed; a long tow is not automatically a restricted-manoeuvrability operation.
Rule 24(a)(v), (e)(iii) · Day shapes
A diamond indicates a tow exceeding 200 m measured from the stern of the towing vessel to the after end of the tow. It is displayed by the towing vessel and the towed vessel or object where prescribed; a long tow is not automatically a restricted-manoeuvrability operation.