SEAir was the original mini scow on which David Raison smashed the 2011 Mini Transat, regularly sailing 2-3kt faster than her rivals. The SEAir project is using the Mini as an experimental platform rather than to win races – the goal being to achieve reliable flight upwind and down with next-generation control systems. The long, curved boards are similar in concept to the Quant 23 (issue 427)
‘We really feel the foil starts to work
properly at around 13kt of speed; at 18kt we are flying. We recorded 24kt on the GPS quite early in testing,’ said skipper Quentin Vlamynck. ‘Beyond that I no longer looked at the
dials that day, I had too much water in my eyes! The game, in terms of successful nav- igation, will be finding where to place the cursor, between good average speed and much faster bursts of really crazy pace.’ Designer Romaric Neyhousser insists
that Arkema 3 was not designed to fly permanently. ‘I’m not even sure that a real flying boat is effective on a transatlantic race. The objective is to have foils that can be deployed quickly and easily, but to fly only when conditions are ideal. ‘Actually, we fly much more often than
I ever expected… and this in spite of the boat currently weighing 150kg more than it should. It is as if we have two big crewmembers hiding down below!’ Not surprisingly, the Arkema team is
still far from having trialled all the differ- ent modes of flying that are possible, given the large number of variables in play. With the shaft close to vertical, flight is
more immediate, but the appendix then behaves like an L-shaped foil which is, by nature, unstable. With the shaft ‘lying’ more horizontal, the immersed part forms
32 SEAHORSE
a V, favouring self-adjusting flight: when the boat rises lift decreases, when it goes down it increases. ‘But even this configuration is delicate,
and preserving righting torque is very important. And unless you sail really hard – and bravely – it is not easy in heavy seas where the tip is often in the air.’ Currently Neyhousser is working on a second gener- ation of foils, delivering more lift and more tolerant, that should fly 2kt earlier and across a wider range of conditions.
SEAir Meanwhile, in Lorient, rival syndicate SEAir has been flying the original scow Mini 747 since late January. The boat’s designer, Mini Transat winner David Raison, has of course been a part of the adventure from the beginning. In fact, SEAir, which has also recruited skipper Bertrand Castelnérac, a well-known GC32 and Moth expert, is not a racing team. It presents itself as a start-up whose objective is not to compete for the transat, but to develop the knowhow of flight, and then to commercialise it. ‘If the Imoca does not fly,’ says SEAir
founder Richard Forest, ‘it’s because her foils really only go up and down. Flight involves multidirectional foil control.’ Mini 747 has been heavily modified and is
currently fitted with a single foil on the port side: it only flies on starboard tack. The long, curved appendage was drawn
by DSS-inventor Hugh Welbourn and is inspired by the foils on his successful Quant 23 lake racer: the wide, curved foil delivers lift downwind, creating both an increase in stability (ie righting moment and power) and lift force. This test foil benefits from integral sensors that monitor loads and deformations across the section. In addition to the in-out setting, the
SEAir foil can be rotated in three further degrees of freedom: cant, rake, and toe- in/toe-out. These adjustments are made using notched wheels and screws, similar to the system fitted to the Flying Phantom and GC32 catamarans. ‘On our first voyages we were immedi-
ately in the air,’ says David Raison, ‘when she flew faster than we ever imagined. ‘But developing these flying monohulls is a long process, there is no point in rushing it. Currently we are able to reach at true wind angles below 90°. Our next goal is to fly at a TWA of 60° and in no more than 12kt of wind…’ And downhill? ‘We are still sailing with
flat sails and to move ahead we need to add more power; one thing at a time, though!’ In current trim Mini 747 is outside class rules. With a second foil it would exceed w
SEAIR/QUESNEL
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