An Ultim trimaran in flight rests on four legs
In flight, an Ultim rests on 4 points of support:
- the leeward foil
- the rudder of the float
- the rudder of the central hull
- central hull drift
In order to ensure flight stability, various settings are available to make the best use of the foil and the leeward rudder. The rake (incidence) and depth of the foil rudders are variable according to a multitude of sailing parameters.
In the end, when the trimaran flies above the waves, the submerged surface area is around 4m2, compared to 20m2 in static conditions.
A new setting for the Jules Verne
Like most Ultim class trimarans, Sodebo is equipped with two steering wheels, which the helmsman chooses according to the tack.
However, a steering wheel with a smaller diameter is installed in front of the helm station, where a crew member is seated in a bucket seat. This equipment was installed during the preparation work for the Jules Verne in 2020.
Sodebo's daggerboard, with a draught of 5m, is equipped with a skate wing type bearing surface, which provides additional support to stabilise the boat's longitudinal trim. As the Ultim class prohibits the use of electronic assistance, a crew member must manually regulate the inclination of this support plan.
Like a headsail trimmer who has to constantly adjust his sheet, the crew member constantly monitors the boat's trim and applies an appropriate action. He has these indications on a screen installed just in front of him. Depending on the data, the trimaran is either pushed or pulled on the bearing surface to ensure a homogeneous and linear trim of the trimaran.
