A shared seaplane seat to Maratua only exists when a resort, liveaboard or dive club has already chartered the aircraft and is reselling spare capacity — it is never a scheduled seat you can buy on its own. Book a private, whole-aircraft charter instead when your group controls its own dates, needs cargo room for dive gear, or wants a fixed arrival window tied to boat connections. As of September 2026 neither option has a published fare; every seaplane quote for Berau to Derawan, Maratua or Kakaban is arranged case by case, subject to operator approval and current permits.
Why doesn’t “shared seaplane” mean the same thing as a shared boat?
A public speedboat from Tanjung Redeb harbour runs on a real timetable — first departure around 08:00, last around 16:00, roughly two hours to Maratua, Sangalaki or Kakaban. Anyone can buy a ticket, and the boat leaves whether it’s half-empty or full.
A seaplane works differently because no scheduled seaplane service to Derawan or Maratua exists yet. Maratua is the only island in the archipelago with an airstrip, served by Wings Air twice weekly; Derawan, Kakaban and Sangalaki have no airport at all and are always reached by boat. Any seaplane movement into this region is a one-off charter, arranged by whoever is paying for the aircraft that day. A “shared” seat is simply a spare seat on somebody else’s charter — a dive resort filling four seats for its own guests and offering the other two, or a liveaboard operator repositioning staff and opening the remainder to paying travellers. There is no booking desk selling loose seats independently of a charter, because there is no fixed route to sell.
This matters for planning. If you ask for a seat-share and none of the resorts or operators currently active in the Kalimarau–Derawan corridor happen to have a charter running on your dates, there simply is no shared option to book — you either wait, join a group booking, or move to a private charter.
How does seat-share actually get arranged?
In practice, a seat-share only becomes available through three channels:
- A dive resort on Maratua or Derawan has already committed to a charter for its own arriving guests and confirms it has spare capacity.
- A dive club or liveaboard operator books a charter for a group trip and opens remaining seats to fill the aircraft and lower the per-seat cost.
- A coordination desk — such as a private seaplane charter broker — is already holding a confirmed charter for one client and can offer the spare capacity to a second small party heading the same direction on the same day.
None of these are standing offers. Each depends on someone else’s schedule lining up with yours, on the aircraft’s actual seat and weight capacity for that sector, and on the operator confirming the water landing is approved for that date — Indonesian seaplane operations into East Kalimantan remain subject to operator approval, authority permits and prevailing conditions, and no designated water aerodrome for the Derawan archipelago is documented as of September 2026.
What do you actually give up by sharing a seat?
Sharing cuts cost per head but removes control over four things: departure time, routing, cargo allowance and who else is on the aircraft.
| Factor | Shared seat | Private (whole-aircraft) charter |
|---|---|---|
| Departure time | Fixed by the primary charterer’s schedule | Set by your group |
| Routing / stops | Follows the resort or group’s itinerary | Direct to your chosen island |
| Dive gear & baggage allowance | Shared with other passengers; often tight | Full aircraft allowance for your group |
| Group size flexibility | Limited to whatever seats are left | Whole aircraft, any mix of guests |
| Availability | Only exists when someone else has already chartered | Bookable whenever an operator can confirm the aircraft and permits |
| Cost logic | Lower per person, but priced by the primary charterer, not a fixed tariff | Higher total cost, split however your group agrees |
Dive travel involves regulators, BCDs, fins, camera housings and sometimes a spare cylinder — weight that a shared charter, already loaded with another party’s gear, may not be able to absorb. Liveaboard operators publish phinisi charter rates, which vary by season and operator, as a reference point for what whole-vessel exclusivity costs in this region; seaplane charter pricing follows a similar logic of quote-on-request rather than a fixed per-seat fare, so treat any number you’re quoted as specific to that date, aircraft and route rather than a published tariff.
Which option fits which kind of traveller?
| Traveller type | Better fit | Why |
|---|---|---|
| Couple, flexible dates | Shared seat, if one is available | Lower cost per person; two people rarely fill a light aircraft anyway |
| Dive club or group of 6+ | Private charter | Group already close to filling the aircraft; scheduling control matters more than per-seat savings |
| Family with children | Private charter | Full baggage allowance, no coordination with unrelated adult divers, flexible timing around kids |
| Solo diver on a tight budget | Shared seat or road-plus-boat combo | Road from Kalimarau to Tanjung Batu runs about 2 to 2.5 hours, then roughly 30 minutes by speedboat to Derawan — a proven, bookable alternative when no seaplane seat is going spare |
| Liveaboard guests needing a fixed rendezvous time | Private charter | A liveaboard’s own departure window doesn’t bend around a resold seat’s schedule |
For most solo and budget travellers, the honest comparison isn’t shared-seaplane versus private-seaplane — it’s seaplane versus the boat-and-road route that already runs every day. Door to jetty for Derawan via Berau totals roughly three hours by road and speedboat combined, and that route has fixed, verifiable timing. A seaplane only earns its premium when it saves real hours or solves a logistics problem the boat route can’t, such as a same-day connection from an international flight into Kalimarau.
What should you ask before paying any deposit?
Whether you’re offered a shared seat or quoted a private charter, get these answered in writing before money changes hands:
- Is the water landing at the destination confirmed and permitted for this specific date, or still pending operator/authority approval?
- What happens to your deposit if the primary charterer cancels or the flight is weathered out — for a shared seat, you are dependent on someone else’s trip going ahead?
- What is the maximum baggage and dive-gear weight allowed per passenger, and is that firm or negotiable?
- Who is the aircraft operator, and is the quote coming directly from them or through a coordinating desk arranging the charter on your behalf?
- Is the price per seat, per aircraft, or a package that includes ground transfer from Kalimarau Airport to the departure point?
- What is the cancellation and rescheduling policy if Berau weather or sea conditions delay the flight?
- If the seaplane can’t fly, is there a fallback plan using the standard road-to-Tanjung Batu-to-speedboat route, and who arranges it?
A resort or broker that can’t answer the permit and cancellation questions clearly is not ready to take a deposit yet. Given that no seaplane operator, water aerodrome or fixed tariff for the Berau–Derawan corridor is publicly documented as of September 2026, treat every quote — shared or private — as a bespoke arrangement, confirm it against the boat-and-road benchmark times above, and get the fallback plan in writing before you commit.
Frequently Asked Questions
Can I book a shared seaplane seat to Maratua directly, without going through a resort?
Not as a standing product. A shared seat only exists when a resort, dive club or liveaboard has already chartered the aircraft and has spare capacity to release. You can ask a coordination desk to flag you for the next available spare seat, but there is no independent booking channel selling loose seaplane seats on a fixed schedule to Derawan or Maratua as of September 2026.
Is a private seaplane charter to Kakaban or Sangalaki even possible, since those islands have no airport?
A seaplane can only land on water, so Kakaban and Sangalaki — which have no airstrip and no documented water aerodrome — depend entirely on the operator confirming a case-by-case water landing under current permits and conditions. Where that isn’t approved, the proven route is speedboat from Tanjung Batu: about one hour to Kakaban, about two hours to Sangalaki.
How much cheaper is a shared seat compared to chartering the whole aircraft?
There’s no fixed answer because no published per-seat or per-aircraft seaplane tariff exists for this route as of September 2026. A shared seat is priced by whoever holds the primary charter, and a private charter is quoted per trip by the operator. Compare any number you receive against the boat-and-road route’s roughly three-hour, lower-cost benchmark before deciding.