Surf / pump foil — 900 mm reference front wing

This is one of foil.tools' own reference designs, published so it can be forked, compared and argued with rather than only loaded.

A 900 mm span front wing in the surf/pump class: mid aspect ratio, an a18 section, and raked tips. Sized to lift early and to keep pumping — which means area and a section with camber, accepting the drag that comes with both.

Why this is a foil.tools design and not a named product

Every commercially sold hydrofoil wing this would be more interesting to compare against is undocumented. Manufacturers publish span, area and a projected-area number, and nothing about the section or the distribution — which is exactly enough to be unable to reproduce one. Rebuilding a manufacturer's wing from photographs would produce a shape that is neither theirs nor honestly labelled, so this library does not do it.

What that leaves is a wing with stated, complete geometry you can actually check. Open it, change the aspect ratio, and see what happens to the numbers. If you have a wing you have measured yourself, publish it — a real measured wing is worth more here than any approximation of a product.

The polars above are foil.tools' own analysis of this model, not published performance data for the aircraft. They are AeroBuildup — strip theory with NeuralFoil sections — for the wing alone, so they exclude the fuselage, the undercarriage and everything else that makes a real aeroplane slower than its wing. Read them for how this shape behaves, and for comparison against the other wings here — not as a figure for the aircraft. Open it in the designer and run your own.