Questions and Answers

Rule 3

General definitions

The answers can be found in the respective Rules and Paragraphs in the book"International Regulations for Preventing Collisions at Sea (Colregs) by Capt. Pierre Deseck and/or in the Colregs Presentation (on DVD), also by Capt. Pierre Deseck

Question 3-1
Define the word “vessel”.

Answer 3-1
Rule 3 (a) and Par. 3.2, Vessel.
Click on vessel for a summery.


Question 3-2
Is the purpose for which a vessel was built of any importance in the Rules. Explain.

Answer 3-2
Par. 3.1, General, third paragraph.


Question 3-3
What types of craft does the word “vessel” include ?

Answer 3-3
Rule 3 (a) and Par. 3.2, third paragraph.
Click on types of craft for a summery


Question 3-4
Define the term “power-driven vessel”. Give extra comment regarding the immediate use of the vessel’s machinery.

Answer 3-4
Rule 3 (b) and Par 3.3, Power-driven vessel.
Click on power-driven vessel for a summary


Question 3-5
Is the power of a ship’s engine important. Explain

Answer 3-5
Par. 3.3, Power-driven vessel, fourth paragraph.


Question 3-6
Define the term “sailing vessel”.

Answer 3-6
Rule 3 (c) and Par. 3.4, Sailing vessel.
Click on sailing vessel for a summary


Question 3-7
What is the condition of a sailing vessel with engine running and disengaged propeller ?

Answer 3-7
Par. 3.4, Sailing vessel.
Click on condition of sailing vessel for a summary


Question 3-8
What is the status of a yacht under sail with engines not running ?

Answer 3-8
In that case the yacht is to be considered as a sailing vessel, even though she has an engine on board. If for instance, the yacht finds her­self in an awkward situation where the use of her engine is imperative, it is not sure that her engine WILL start immediately. According to Mur­phy’s Law, the engine will fail to start when you really need it to start.

On the other hand, when the engine is running with the propeller disen­gaged, you are virtually certain of the use of your engine. You simply have to engage the propeller.


Question 3-9
When is a vessel considered as being engaged in fishing ?

Answer 3-9
Rule 3 (d) and Par. 3.5, Vessel engaged in fishing.
Click on engaged in fishing for a summary


Question 3-10
What is the status of a fishing vessel leaving the harbour, en route to het fishing grounds ?

Answer 3-10
While en route to her fishing grounds, a fishing vessel must be consid­ered as a ordinary power-driven vessel and comply with all the rules ap­plicable to that type of vessels.

Only when she has reached het fishing ground and starts to pay out her fishing gear, will she be considered as a vessel engaged in fishing.


Question 3-11
Define the word seaplane.

Answer 3-11
Rule 3 (e) and Par. 3.6, Seaplane.


Question 3-12
What is to be understood by a “vessel not under command (NUC) ?

Answer 3-12
Rule 3 (f) and Par. 3.7, Vessel not under command.
Click on NUC for a summary


Question 3-13
Give some examples of vessels being partially not under command.

Answer 3-13
Par. 3.7, Vessel not under command.
Click on parially NUC for a summary


Question 3-14
Give some situations of a vessel being entirely not under command.

Answer 3-14
Par. 3.7, Vessel not under command.
Click on entirely NUC for a summary


Question 3-15
Define the term “vessel restricted in her ability to manoeuvre”. Give some examples.

Answer 3-15
Rule 3 (g) and Par. 3.8, Vessel restricted in her ability to manoeuvre
Click on restricted to manoeuvre for a summary


Question 3-16
Define the term “cable ship”.

Answer 3-16
Par. 3.8 (i), Vessel restricted in her ability to manoeuvre.


Question 3-17
Define the term “vessel constrained by her draught”.

Answer 3-17
Rule 3 (h) and Par. 3.9, Vessels constrained by their draught.
Click on vessel constrained by her draught for a summary


Question 3-18
Does the term “deep draught vessel” apply to sailing vessels ?

Answer 3-18
Par. 3.9, Vessels constrained by their draught, fourth paragraph.


Question 3-19
Does the term “vessel constrained by her draught” only apply to vessels of very large size and tonnage ?

Answer 3-19
Par. 3.9, Vessels constrained by their draught, second paragraph.


Question 3-20
When can a vessel be considered as being “underway” ?

Answer 3-20
Rule 3 (i) and Par. 3.10, Underway.
Click on underway for a summary


Question 3-21
What is the difference between the expressions “making way through the water” and “not making way through the water”.

Answer 3-21
Par. 3.10, Underway.

 A vessel can be making way though the water and not be moving with regard to the bottom, when the vessel is moving straight into the current and the speed and course of the vessel is equal to the speed and direc­tion of the current.

On the other hand, a vessel may be stopped with regard to the water and be moving with regard to the bottom, in the direction and at the speed of the current (not taking the direction and speed of the wind into account).

In theory, the current must be considered as a mass of water moving in a certain direction and with a certain speed and taking with it everything that is in the water. Not taking the effect of the wind or any other atmos­pheric element into consideration, a vessel of any size (large or small) and a matchbox will drift at the same speed and in the same direction under the influence of the same current.

Click on making way through the water for a summary


Question 3-22
When a vessel’s anchor is dragging, is she underway or not underway ?

Answer 3-22
Par. 3.10, Underway, last paragraph.


Question 3-23
When are vessels deemed to be in sight of one another ?

Answer 3-23
Rule 3 (k) and Par. 3.12, Vessels in sight of one another.
Click on in sight of one another for a summary


Question 3-24
Define the term “restricted visibility.”

Answer 3-24
Rule 3 (l).
Click on restricted visibility for a summary


Question 3-25
Define the term “WIG craft”

Answer 3-25
Rule 3 (m) and Par. 3.14, WIG craft.
Click on WIG craft for a summary


Question 3-26
What is the difference between a vessel “underway” and a vessel “mak­ing way” ?

Answer 3-26
A vessel “underway” is a vessel that is not attached to any fixed object such as the shore, the bottom or at anchor.

A vessel “making way” is a vessel that floats on the water without any attachement to a fixed object or the bottom. It can be making way though the water which means that it is moving with respect to the water (with or withour engines running) or it can not make way through the wa­ter which means that it is stopped with respect to the water. See also Par. 3.10, Underway.

About 1500 slides and 50 animations are available on our DVD Colregs Presentation which can be purchased online (click on books or read the books).