Derwent Raider Test Sail
‘Albuera’ (a Derwent Raider) passed her sailing trials with ease on a mild, sunny afternoon on the Derwent River in Hobart, Tasmania April 2011). The new Derwent Raider was named by the younger boys in the Travers family before they went to live on mainland Australia. Their dad Tristram and older brother Clancy built the boat in the Witt Design / Row and Sail workshop as their time permitted over several months. They had supervision and support from Allan.
She is well balanced and tracks beautifully. The boat is easily driven and points well. The balance remains stable through different angles of heel and the sail area is just right for a narrow easily driven hull. While the boat is slow to go about because of the skeg that is needed for rowing, it goes about reliably. The Derwent Raider heels freely to start with but the hull’s stability rapidly increases as it heels and finds a comfortable ‘groove’ to suit the wind. This is in keeping with a hull form that permits great rowing with a sliding seat.
Here are some more features that were confirmed in the sailing trial:
- The centre-board locating mechanism works really well. It is held in place by a hinged board that has closed cell foam attached to it. This simultaneously seals the top of the centre-case, holds the centre-board in position and allows the centre-board to rotate aft without damaging the boat if it hits something like a rock or log. The self draining cockpit drains through the centre-case slot because its sides do not extend above the floor. This means that there is no obstruction to moving across the boat and nothing to get in the way of the sliding seat. It is a great resolution to an age old annoyance in small sailing craft.
- The vertical sliding rudder is convenient and is much easier than a swinging one. This concept was drawn from racing dinghys. It is particularly valuable in the case of the Derwent Raider where the person sailing sits in the middle of the boat and well forward of the stern. It is not hard though to reach back and lift the rudder. It would be much more difficult to reach over the stern to encourage up a pivoting rudder blade. The alternative of control lines for a pivoting rudder blade are removed. Simplicity is usually the best.
- The mast is really light and handled easily by one person. It was beautifully made by Croker Oars with reinforcing where the side forestays attach. Again there was a bit of Witt innovation involved with the stays being attached to a fitted stainless steel collar which avoided the need for any internal bracing. It also permitted using a light-weight and flexible PVC extruded sail track from C-Tech in New Zealand. The mast is raked well aft so that the sail sheets almost like a jib. The mast flexes under load, flattening the sail when needed.
- The 5 square metre sail has no boom. This has some great advantages. The sail is set quite low and is simply sheeted like a jib with the mainsheet running to a sheeve that slides across a rope hause. There is no boom to belt your head and there is no clutter from a boom, wishbone or sprit. What is very satisfying is that this rig balances really well on all points of sailing. You would typically expect the centre of effort on the sail to move more forward more rapidly on this rig compared with a sail with a boom, sprit or wishbone. The net result could be increased weather helm as the boat comes ‘off the wind’ (moves away from pointing or being close haued). But this is not the experience in this boat and is probably due to the skeg that is there for rowing.
All in all, the trials demonstrated that the Derwent Raider’s sailing capabilities have met our expectations. The rig in reefed form has yet to be trialled in windy conditions.
Derwent Raider Test Sail - stern quarter
The building process was a father/son effort where they have joked about ‘the son getting the experience and father getting to keep the boat.’ We think that Tristram got a fair bit of experience too!
As a further note: Visitors to the Australian Wooden Boat Festival in February 2011 agreed that the new Derwent Raider has a very satisfying look. Many really enjoyed seeing the concept of a boat that rows and sails well. The Derwent Raider mold with a partially built boat was on display at the Festival so that people could see how they are built.
