Question 1

(Considering midship, end, side or intermediate compartment

Accepted Answer

Floodable length is the longest compartment you can flood at any point without drowning the margin line — position on the ship sets it. Floodable length is measured with the ship upright at each point along her length as the centre. Permeability decides how much water the space can hold — empty holds near 100%, machinery far less. Permissible length is floodable length times the factor of subdivision, tighter amidships where the curve is longest. End compartments flood shorter safely than midship ones; side and intermediate compartments count their own permeability. Surveyor follow-up: midship hold versus forepeak of equal length — which floods deeper, and what curve proves it?

Question 2

Draw a typical load line displayed at the side of a ship, briefly explain the features of load line

Accepted Answer

Sketch deck line, disc and seasonal grids: the Plimsoll mark states how deep she may load in each zone and season. Deck line 300 by 25 mm through the freeboard deck upper surface — the datum every mark hangs from. Load-line disc 300 mm across with a horizontal bar whose upper edge is the summer salt-water line. Seasonal grid: tropical, summer, winter and winter North Atlantic lines plus fresh-water allowances, punched in steel and painted for contrast. Timber marks ride alongside where deck cargo buoyancy earns deeper loading except in the harshest zone. Surveyor follow-up: draw the mark and point at the line she loads to in fresh water in summer — then in tropical salt.

Question 3

Load line marking

Accepted Answer

Load-line marks are punched steel painted for contrast: deck line, disc and seasonal grid stating allowed depth in every zone. Deck line 300 by 25 mm on the freeboard deck edge; disc 300 mm across with summer bar through its centre. Seasonal lines 230 by 23 mm off a vertical 540 mm from the disc for tropical, summer, winter and winter North Atlantic. Punched into the hull so fading paint never hides them, painted white or yellow on dark steel and black on light. Timber marks ride alongside where deck cargo buoyancy earns deeper loading. Surveyor follow-up: marks legible but the disc bar rusted thin — accept, chip and paint, or re-punch?

Question 4

Draw plimsoll marking (paper pen

Accepted Answer

Draw the Plimsoll mark amidships: circle with deck line above, seasonal ladders beside, draft tied to freeboard. Circle bisected by the summer load line with S at centre, deck line marked above at the freeboard deck. Seasonal ladder beside: T above S for tropical, W below for winter, WNA further for North Atlantic winter. Fresh-water allowances sit outboard — F above S, TF above T — by the density correction to summer draft. Lumber and passenger marks add where assigned; every line must clear water for its zone and season. Surveyor follow-up: draw TF above T by FWA with S awash in dock water — legal to sail for winter North Atlantic or not?

Question 5

Load line survey

Accepted Answer

Load Line survey proves weathertight integrity for five years: initial, renewal and yearly checks on marks and appliances. Initial survey before service with renewal inside five years and annual checks within three months either way of anniversary. Inspect hull condition, superstructure ends, hatches with cleats and wedges, machinery openings and ventilator closures. Prove deck line, load-line marks and draught marks legible with freeboard assignment matches. Extension past expiry runs three months maximum to reach the survey port — never as trading grace. Surveyor follow-up: annual window missed by four months with marks freshly painted — valid, void or detained?

Question 6

Loadline, what will happen when ship goes to sw from fw

Accepted Answer

Going from fresh water to sea water, the same weight lifts her less, so the draught falls and the freeboard rises. Denser water gives more buoyancy for the same immersed volume, so the ship rises to a shallower draught. The freeboard, measured to the deck line, therefore increases by roughly the fresh water allowance. That is exactly what the load line marks encode: the summer line in salt water, the F and TF lines in fresh. Leave a river port light, burn your own fuel and stores, and you can load that much more cargo to reach the summer line at sea. Surveyor follow-up: ship loaded to the F line in a dock with the summer mark nearly awash at sea — legal, and by what margin?

Question 7

Structure of type a (layers), b, c and membrane tank

Accepted Answer

Types A, B and C are graduated structural standards for tanks, and a membrane tank is the flexible alternative to all three. Type A tanks are built to the highest standard, with full girder subdivision and testing, used where the highest reliability is required. Type B tanks allow a reduced subdivision with buckling calculations used in place of the full test, and Type C is the unprotected structural tank using only analysis. A membrane tank is a flexible, thin-walled compartment bonded to the hull shell, so the hull itself carries the liquid pressure. Because it works on the shell, a membrane tank saves weight and allows double-banking, at the cost of restricting what may be carried in it. Surveyor follow-up: membrane tank with a heating coil strapped to it — which part of the arrangement is the restriction?

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