Reading a General Arrangement Plan Before You Shortlist
Updated: August 2026
A general arrangement plan is the deck-by-deck drawing that shows where every cabin, tank, bulkhead and passageway sits. Read it before the photographs. Three checks — crew circulation, tank placement, and whether the drawing matches the tonnage certificate — eliminate most unsuitable hulls in twenty minutes, without leaving your desk.
What the drawing is, and what it is not
The general arrangement plan, universally shortened to GA, is a set of plan views: one per deck, usually with a profile view showing the vessel in side elevation. It is a layout document. It is not a structural drawing, it does not certify anything, and it is not proof that the vessel was built to the plan. What it does give you is the only complete spatial description of the hull you will see before you stand on it, and unlike a photograph it cannot flatter.
On Indonesian phinisi listings the GA is frequently missing, and its absence is informative. A yard that built the vessel has the drawing. An owner who has refitted the vessel and moved bulkheads may not have an updated one, which is itself worth knowing. A broker who cannot produce a GA is usually several steps removed from the actual owner.
Check one: can the crew move without crossing guests?
Trace the route a crew member takes from the crew quarters to the galley, from the galley to the saloon, and from the engine room to the deck. On a well-drawn phinisi those routes stay separate from guest circulation for most of their length. On a poorly converted hull the only path from the crew mess to the galley runs straight through the guest saloon, which means every meal service, every cleaning round and every night watch changeover crosses the guest area.
This single check predicts charter reviews more reliably than cabin size does. It also predicts crew turnover, because a crew with no private circulation has no off-duty space at all.
Check two: where are the tanks, and how many are there?
Fuel and fresh-water tanks are heavy, and their position governs trim. A GA that shows all fuel in a single tank forward of midships is describing a vessel that changes trim noticeably as it burns through a passage. Multiple smaller tanks with a transfer system cost more to build and are markedly better to operate.
Count the tanks, note their positions, then compare the total against the capacity claimed in the listing text. Disagreements between the drawing and the sales copy are common and always worth raising early — see verifying tank capacities for the measurement method that settles it.
Check three: does the drawing agree with the tonnage certificate?
The surat ukur states registered length, breadth, depth and gross tonnage. Lay those figures against the GA. A hull whose drawing shows an extra deck level, a lengthened aft platform or an enclosed sky lounge that the tonnage certificate does not reflect has been modified without re-measurement. That is not necessarily fatal, but it must be corrected before the sale completes, because the registry entry has to match the vessel. Tonnage certificates explained covers what each number on that document means.
What the GA tells you about charter viability
- Cabin symmetry. Four equivalent doubles charter more easily than one large master plus three small twins, because agents sell by the cabin.
- En-suite count. Shared heads reduce the achievable weekly rate more than most owners expect.
- Deck space per guest. Divide usable open deck area by guest capacity. Below about two square metres per guest the vessel feels crowded at anchor regardless of length.
- Tender stowage. A drawing with no dedicated tender position means the tender ends up on the sun deck, occupying the space guests paid for.
- Dive platform and compressor room. Retro-fitting either is expensive; the GA tells you immediately whether they were designed in.
Reading the profile view
The side elevation shows freeboard, superstructure height and the waterline. Two things matter. First, superstructure mass high above the waterline raises the centre of gravity, which links directly to the stability question covered in cabin count versus stability. Second, the drawn waterline against the actual loaded waterline in recent photographs tells you whether the vessel floats where the designer intended. A hull sitting visibly below its drawn line is carrying weight it was not designed for.
Turning the GA into questions
The purpose of reading the drawing before survey is to arrive with specific questions rather than general ones. Good questions sound like: the GA shows two 4,000-litre fuel tanks, the listing says 10,000 litres, which is correct and when was it last sounded? Or: the sky lounge is not on the tonnage certificate, when was the vessel last re-measured? Those questions cost nothing and either produce documents or produce silence, and both answers are useful.
Request the vessel dossier
Ask for the GA plan and the tonnage certificate together on any hull you are considering — we send them as a pair. WhatsApp +62 811-3941-4563 or write to [email protected]. All figures on this site are quoted in USD.
Frequently asked questions
What is a general arrangement plan on a phinisi?
It is the deck-by-deck layout drawing showing cabins, tanks, bulkheads, machinery spaces and circulation routes, usually with a side profile view. It is the most complete spatial description of the vessel available before a physical inspection.
Is a GA plan the same as a stability booklet?
No. The GA shows layout; the stability booklet contains the calculations proving the vessel stays upright under defined loading conditions. A serious listing should be able to produce both, and the stability booklet matters more once a vessel carries paying guests.
What if the seller has no GA plan?
Ask which yard built the hull and whether the yard retains the drawing, since many do. If no drawing exists anywhere, budget for a surveyor or naval architect to measure and draw one — you will need it for insurance, certification and any future refit.
Does a modified layout invalidate the tonnage certificate?
Structural modifications that change enclosed volume require re-measurement and an updated certificate. Until that is done the registry entry does not describe the actual vessel, which will block or delay an ownership transfer.
Phinisi Boat For Sale is a specialist maritime brand and digital platform under Juara Holding Group. Vessel-sale, construction, refit and repair contracts are issued by PT Komodo Galangan Nusantara. Brokerage, central agency and charter-marketing contracts are issued by PT Komodo Bahari Nusantara. Separate contracts, separate fees, separate ledgers.
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Written and checked by the desk. Figures are dated at the point of writing — our editorial standards explains how, and what happens when something here turns out to be wrong.
