1.2 Loadline Convention (Challenge Questions)

Question 1

Find the difference between the minimum freeboards of Type A and B for 252m length.

Answer 1

As per Freeboard Table:
Type A - 3024mm
Type B - 4045mm

4045-3024=1021mm

Question 2

List the 2 criteria under which AMSA will issue an International Load Line Exemption certificate.

Answer 2

• The vessel has completed the initial or renewal survey.
• For a vessel that is to undertake a single international voyage — AMSA is satisfied that the vessel complies with safety requirements that are adequate for the voyage to be undertaken.

Question 3

Describe the circumstances under which AMSA might cancel the LLC of an Australian-flagged vessel.

Answer 3

(a) the hull or superstructures of the vessel are altered to the extent that assignment of increased freeboard is required.
(b) the structural strength of the vessel has been lowered to the extent that the vessel is unsafe.
(c) a condition of the certificate has been breached.
(d) a condition of exemption has been breached.
(e) the vessel to which the certificate applies ceases to be registered in Australia.
(f) the owner of the vessel asks in writing that the vessel’s certificate be revoked.
(g) the certificate contains incorrect information.

Question 4

What will be the effect on the ship’s draft when she moves from Summer to Tropical load line zones?

Answer 4

Ship’s draft will increase due to the difference in density.

Question 5

A vessel is intending to sail after loading from Argentina (Winter zone) to Italy (Summer zone). Vessel ETD is 1st May and ETA is 20th May. Use the loadline chart given below to determine to which load line can she safely load with maximum cargo.

Answer 5

Winter Loadline.

Question 6

Where’s the worse area to sail as per Load Line Convention?

Answer 6

North Atlantic during winter months.

Question 7

What is reserve buoyancy?

Answer 7

The difference between the volume of a hull below the designed waterline and the volume of the hull below the lowest opening incapable of being made watertight.

Question 8

What is meant by seasonal loadline?

Answer 8

Always load to the lowest loadline.

Question 9

A passage from Hobart to the Gulf, which loadline to load to?

Answer 9

• Load to winter zone.
• Avoid winter zone, head north (Able to load to summer loadline.)

Question 10

Which loadline is the same for other ships and timber carriers?

Answer 10

Winter North Atlantic

Question 11

Describe port and stbd loadline.

Answer 11

From Stbd side

Question 12

Other than the ship’s side where else can the load line be found?

Answer 12

i. Load Line certificate.
ii. Intact Stability Booklet.

Question 13

What’s the difference between stress and stability?

Answer 13

Stress - Internal and/or external
Stability - Trim and GMf

Question 14

Difference between weathertight and watertight?

Answer 14

Weathertight fitting shall withstand water pressure from the outside but above a certain pressure, there will be ingress of water.

Watertight fitting shall withstand water pressure from both sides.

Question 15

What is a permeability of a compartment?

Answer 15

Permeability of a compartment in a ship is the percentage of empty volume in that space.

Permeability is used in ship survivability and damaged stability calculations in ship design.

A fully loaded tanker would have around 98% of the tank volume occupied by cargo.

Also, the pressure exerted by the liquid cargo would limit the amount of water that can enter the ruptured compartment.

Question 16

When is it legal to submerge past the load line.

Answer 16

• SAR
• Listing
• Fire-fighting in the ER.
• Long-river passages.
• If flag state gives a dispensation.

Question 17

As a Chief mate onboard a timber carrier carrying timber cargo from Hobart (Tasmania) to Jebel Ali (UAE). Take a printout of the load line zone diagram (from MyLO or the web), draw a rough route between these ports and find out the load line zones you would be transiting. Find out the load line up to which you will load your vessel. Can you submerge the summer load line when departing Hobart?

Answer 17

Load line zones: Winter, Summer and Tropical

Only be able to load to Winter Load line. Unless the passage goes through the northern route which won’t pass through the winter zone.

Question 18

Use the loadicator software (for a bulk carrier) provided in the web resource section. Create a condition where your cargo is at 100% capacity and your vessel is upright and even keel. You can make assumptions as required.

(Based on TPC, calculate the extra cargo to be loaded.)

Question 19

(i) You are the Chief Officer and your vessel has to transit Summer, Tropical and Winter load line zones (in that order) in your upcoming laden voyage. To which of these load line marks, would you load your vessel, to comply with the International Convention on Load Lines (1966)? State the reason behind your answer.

(ii) Describe five (5) circumstances under which you may depart the load port with this limiting load line (as per above question) submerged?

Answer 19

(i) If the passage is as per the question and the vessel would be proceeding from summer to tropical and to winter, I would load the vessel to the Summer loadline, as when the vessel approaches the final destination, fuel, provisions and water would be used up and the vessel would be able to rise to the winter loadline.

(ii)
1. If the dock water density is less than 1.025 t/m3 as measured by a load line hydrometer. If the vessel is in FW, she can submerge the appropriate mark by the amount of Fresh Water Allowance (FWA), and if in brackish water, by the Dock Water Allowance (DWA).
2. A vessel may depart from an upriver wharf loaded beyond the assigned draught by an amount equal to the consumption of fuel stores and other consumables that will be used up before the vessel reaches the open sea.
3. A small list is permissible so that the Plimsoll line on one side is submerged but the other side is exposed. In this case, the mean draught at the Plimsoll line must not exceed the assigned summer draught.
4. With the written approval of the Administration. (e.g. rescue at sea).
5. Incidences of Force Majeure. (e.g. firefighting, heavy-weather damage, etc.)