Draft is a commercial decision disguised as a hydrostatic one. It determines which anchorages you can overnight at, which determines what itinerary you can sell. Derive it from the specific list of sites you intend to use, checked against charted depths and swinging room at your intended anchor scope — not from a rule of thumb about vessel length.
Why draft matters more in Komodo than elsewhere
The park’s value to a dive operation is the diversity of sites within a short steam of each other, and many of the good overnight anchorages are inside bays, behind headlands or along reef edges where depth changes quickly. A vessel that draws less can tuck in closer, anchor in a more sheltered position, and reduce the tender run to the dive site. A vessel that draws more sits further out, swings wider, and gives its guests a longer, wetter tender ride before every dive.
Guests do not read hydrostatic tables, but they absolutely notice a fifteen-minute tender transit in chop at six in the morning.
What deeper draft buys
Directional stability and better tracking, particularly relevant in the tidal streams that run through the park’s straits. More volume low in the hull for fuel and water tankage, which improves both range and stability. Better propeller immersion and generally better seakeeping in the open water sections of a longer itinerary out toward Sumbawa or Alor. On a heavier displacement vessel these are not small advantages.
What shallower draft buys
Access. More candidate anchorages, more flexibility to move when wind shifts overnight, shorter tender runs, and less anxiety in poorly charted inner bays where the survey data is old. It also expands your haul-out options — a shallower vessel has more facilities available to it in a region where facilities are already limited. See Labuan Bajo yard and haul-out logistics.
How to actually derive the number
The method we use with owners is unglamorous and it works.
- List the sites. Write down every location you intend to overnight at across your standard itineraries, plus the alternates you would use in a wind shift.
- Get real depths. Charted depth at the intended anchoring position, plus tidal range, plus the shallowest point on the approach. Komodo has significant tidal range, and the number that matters is depth at low water, not the chart datum you glanced at.
- Add scope. Anchoring in current needs adequate chain scope. Work out the swinging circle at that scope and check what is inside it at low water.
- Add margin. Under-keel clearance for a working vessel with guests aboard should be conservative, because the consequence of getting it wrong in a national park is not just a grounding, it is reef damage with regulatory consequences.
- Now you have a ceiling. The deepest draft that keeps your site list intact.
Then check what that draft does to your tankage and stability. If the numbers do not reconcile, something in the operating profile has to give — usually range, occasionally the site list. That negotiation is the actual design work.
Anchoring restrictions change the calculation
Some sites in the park restrict or prohibit anchoring and use mooring buoys instead. Where you will be on a mooring, draft matters for approach and for the depth under the vessel at the buoy, but the swinging-circle calculation is different and the seabed impact question disappears. Building your site list means knowing which are anchorages and which are moorings — see Komodo National Park compliance, because the mooring arrangement on the bow is itself a specification item.
Draft on a refit
You mostly cannot change it. Adding weight during a refit — heavier machinery, more tankage, a stabiliser installation, a rebuilt interior — increases displacement and therefore draft, and owners are regularly surprised to find a refitted vessel sitting noticeably lower and no longer able to use an anchorage it used last season. Weight control during refit deserves explicit attention. See the refit page.
The short version
Fix the site list before the lines plan. Every centimetre of draft is an anchorage you either keep or lose, and anchorages are what you sell. The full specification chain is on the specification guide.
Frequently asked questions
What draft is ideal for a Komodo liveaboard?
There is no universal figure. Derive it from the specific anchorages on your intended itineraries, using charted depth at low water, the shallowest point on the approach, the swinging circle at your intended anchor scope, and a conservative under-keel margin. The deepest draft that preserves your site list is your ceiling.
Does deeper draft help in Komodo’s currents?
Yes, to a point. Deeper draft improves directional stability and tracking in tidal streams and allows more fuel and water low in the hull, which helps range and stability. The cost is fewer usable anchorages and longer tender runs for guests.
Can a refit change a vessel’s draft?
Only in the wrong direction, usually. Added machinery, tankage, stabilisers and interior weight increase displacement and therefore draft, and owners are regularly surprised to lose an anchorage they used the previous season. Weight control during refit deserves explicit attention.
Talk to the build desk
Send the vessel details or the operating profile you want to run and we will tell you what has to be established before a number means anything. Quotations in USD. Construction, repair, refit and vessel-sale contracts are issued by PT Komodo Galangan Nusantara.