Semi-custom Hull Vanes

YERSEKE – The first test of a Hull Vane on an 18.5m (61ft.) aluminum motor yacht has confirmed the performance gains the Dutch maker of the innovative hydrofoil promises.

Gerard Sentse, owner of Yerseke Watersport Service, says he checked the performance of the 18.5m Colinda (photo), with and without the Hull Vane. “In addition to fuel savings and CO2 reduction, the client’s primary concern was to increase comfort,” he says.

“As less power is needed at cruising speed, the Colinda now is significantly quieter. The boat also is more stable and makes fewer waves. The client is very satisfied with the retrofit. We will certainly offer this to our other customers.”

When equipped with the hydrofoil, the Colinda generates less wake, is quieter, achieves fuel savings of at least 20% and sails almost a knot faster.

A Dutch invention, the Hull Vane is a hydrofoil that sits underwater, just aft of the transom and converts the energy of the stern wave into a forward thrust.

Hull Vane BV introduced its patented wing in 2014 for large yachts and commercial vessels. Last year, it launched a ‘semi-custom’ version for water displacement motor yachts of 10 to 20m that have a maximum speed of 20 – 25 km/h (10.8 – 13.5 knots).

Hull Vane in action

The underwater spoiler is a product of Hull Vane BV. To date, more than 30 have gone on commercial vessels and superyachts, all custom units. For the recreational market, the company made a less costly ‘semi-custom’ aluminum Hull Vane. The Colinda test yielded these results:

  • an average 20% cut in fuel use across the speed range. Between 14 and 16 km/h (7.6 and 8.6 knots), that gain rose to 26%.
  • The top speed rose to 23.4 km/h (12.6 knots), from 21.9 km/h (11.8 knots).
  • The Hull Vane gave the yacht a cruising speed of 18 km/h (9.7 knots) at 1440 rpm, down from 1600 rpm.
  • Less engine vibrations made the Colinda 7 decibels quieter

The hydrofoil reduces the stern wave. “This can clearly be seen at all speeds,” says Pieter Duzijn of Hull Vane BV. “At a speed of 15 km/h (8.1 knots), the noise on the aft deck drops from 72.6 dB(A) to 65.6 dB(A).”