Druma — Dwarven Rivercraft
The Goldskimmer Hydrofoil
Dwarven Engineering on Profit's Flow
At rest, the vessel looks too heavy to be fast: a long, narrow hull of dark timber bound in brass, with a low armored cabin and a broad dwarven engine housing occupying much of the stern.
Then the machinery engages.
Brass vanes beneath the hull bite into the river. The bow rises clear of the water, followed by most of the vessel itself, until the craft seems to balance impossibly upon a handful of submerged blades. The pounding of the hull against the current disappears. In its place comes the steady hum of gears, the hiss of spray, and a rapidly retreating shoreline.
The Goldskimmer is a rare dwarven rivercraft designed for rapid transportation along major waterways. Rather than forcing its entire hull through the water, articulated foils beneath the vessel lift most of its weight above the river once sufficient speed is reached.
The result is dramatically reduced drag. A Goldskimmer can cover the Macridi–Kerse route in approximately 35% of the time required by an ordinary commercial riverboat—a reduction of roughly 65%.
| Journey | Ordinary Riverboat | Dwarven Hydrofoil | Time Saved |
|---|---|---|---|
| Macridi → Kerse | About 3 days | About 1 day | About 2 days |
| Kerse → Macridi | About 5 days | About 1¾ days | About 3¼ days |
For play, use the following standard travel times under favorable conditions:
Macridi to Kerse: approximately 1 day.
Kerse to Macridi: approximately 1 day and 18 hours.
The river current still matters. Traveling north toward Kerse allows the Goldskimmer to combine its own propulsion with the flow of the river. Returning south requires the vessel to fight the current, so the upstream voyage remains noticeably longer even with dwarven engineering.
The vessel's underside carries several retractable hydrodynamic lifting blades mounted to reinforced dwarven struts. At low speed the Goldskimmer behaves much like an ordinary shallow-draft boat.
Once its engine reaches cruising speed, water passing over the blades generates enough lift to raise the main hull above the surface. Only the foils and propulsion assembly remain submerged, allowing the vessel to race over stretches of open river that would slow a conventional barge.
A compact dwarven power assembly drives the stern mechanism through a complicated arrangement of gears, shafts, pressure chambers, and precisely machined brass components. Most surface engineers can recognize what the machinery is doing. Reproducing it is another matter entirely.
A Goldskimmer requires a reasonably broad, navigable channel before it can rise onto its foils. Near docks, sharp bends, shallows, debris fields, or heavy river traffic, the pilot must reduce speed and lower the hull back into the water.
Floating timber is particularly dangerous. At hydrofoil speed, striking a submerged log can damage a lifting strut or force the vessel violently off its foils.
Severe storms, unusually low water, mechanical trouble, or extensive debris can therefore erase much of the vessel's advantage.
Speed comes at the expense of capacity. The Goldskimmer carries passengers, messages, valuable cargo, alchemical samples, and other high-priority freight rather than bulk timber or ordinary commercial goods.
Passage is correspondingly expensive, and seats are rarely available without advance arrangements or a particularly persuasive reason for the dwarven crew to make room.
A message or alchemical sample leaving Macridi aboard a Goldskimmer can reach Kerse in roughly a day. If a hydrofoil is immediately available for the return journey, a physical response could theoretically make the complete trip in less than three days of travel time.
Laboratory work, loading delays, availability of a returning vessel, and whatever business awaits in Kerse remain separate from the actual travel time.