Lab 04
Hydrodynamic Test Tank
Validating performance before the first full-scale prototype
We tank-test SUP hull shapes at 1:3 to 1:5 model scale — nose profile, rail radius, rocker and wetted surface — measuring drag, glide efficiency and stability before committing to a full-size prototype. A week in the tank returns the performance data that would take months of full-scale trial and error.
Specifications verified: 2026-08It is a common misconception that hydrodynamic testing is reserved for ships and racing craft. In reality, the performance of a SUP board — a planing hull of 10 to 14 feet — is just as dependent on its underwater shape as any other craft. Nose profile, rail radius, rocker and wetted surface area all have a dramatic effect on drag, glide efficiency and stability. At {SITE.name}, we operate a dedicated hydrodynamic test tank that allows us to quantify these effects at model scale — before committing fabric and tooling to a full-size prototype.
Why tank-test a SUP board?
Testing at model scale (typically 1:3 to 1:5) gives us the ability to iterate board shapes rapidly and cost-effectively. A week in the tank can generate the same performance data that would require months of full-scale trial-and-error — and at a fraction of the cost.
Facility specifications
| Parameter | Specification |
|---|---|
| Tank dimensions | 35 m (L) × 3.5 m (W) × 1.8 m (D) |
| Towing carriage | Electric servo-driven, max speed 12 m/s (23 kn), speed accuracy ± 0.5 % |
| Wave generator | Flap-type, programmable regular & irregular sea states, Hs up to 0.3 m at model scale |
| Instrumentation | 6-component dynamometer (drag, side force, yaw moment), accelerometers, inclinometers, wave probes |
| Data acquisition | Sampling at 1000 Hz per channel, real-time display + post-processing suite |
| Model fabrication | In-house CNC milling and 3D printing for model hulls up to 1.8 m LOA |
Our test programme
A standard board development programme in our tank follows this sequence:
- Model build — A 1:4 scale model is CNC-machined from high-density foam and glassed for rigidity. Weight and centre of gravity are adjusted to match Froude-scaled full-load condition.
- Resistance runs — The model is towed at 6-10 speeds spanning paddling range (2–6 kn full scale). Total resistance is measured and decomposed into frictional and residuary components using the ITTC-1957 method.
- Trim & sinkage measurement — Running trim and sinkage are recorded at each speed. The target is the trim angle that minimises wetted surface while keeping the nose clear of bow wave.
- Wake survey — Transverse wave cuts are measured at two speeds to assess wave-making resistance and identify nose-shape interactions that slow a board through the water.
- Seakeeping (optional) — Head-sea runs in regular waves to measure added resistance and vertical acceleration in chop — the data behind touring board nose design.
- Data analysis & recommendations — A full report is delivered with comparative charts, drag/speed curves, and specific design recommendations for the full-scale board.
Typical Tank Test Results — Drag vs Speed (11''0 All-Around board, 1:4 scale)
Model-scale drag (N) at Froude-scaled speeds. Full-scale power prediction follows the ITTC-1978 performance-prediction method.
Expert team
Our tank is operated by a hydrodynamicist with a PhD in naval architecture and 8 years of towing-tank experience at a major European maritime research institute. He is supported by a technician who prepares all models and instrumentation. The team follows the ITTC (International Towing Tank Conference) Recommended Procedures to ensure that every test is repeatable, traceable, and internationally defensible.
Tank-testing for custom board development
Our tank is not only used for house-designed boards — we regularly run test programmes for clients who want to validate a custom board shape or investigate a performance issue:
- Shape comparison — Two or more candidate board shapes tested under identical conditions, providing an objective drag/speed/stability comparison to inform your design choice.
- Rail and nose optimisation — Nose profile and rail radius variations can be tested in various configurations to quantify their contribution to drag reduction.
- Rider-load study — Resistance data is mapped across the rated rider weight range, allowing you to specify the right length and width for your target paddler.
Why test with us?
We do not just give you a set of raw numbers. Our reports translate tank data into actionable engineering recommendations: "Raise the nose rocker by 10 mm to reduce bow-wave drag at cruise speed", "Round the rail at the midship station to reduce wetted surface", or "Move the standing area 50 mm forward for improved trim". You leave with a clear understanding of what to change and why.
Our tank is also available for independent third-party testing on a fee-for-service basis. If you are developing a board and want an unbiased, professionally executed hydrodynamic assessment, we welcome your enquiry.
Book a tank test session
Whether you need a full development programme or a single comparative test, we can accommodate your schedule.