Flying high

Thomas Jundt talks to us about his foiling 18ft Skiff

By now many of you will have seen the videos of a foiling 18ft Skiff circling the internet. We saw it a while ago and quickly went on the hunt for some more information. After a bit of chasing we managed to make contact with the owner, who promised to speak to us as soon as possible. Here is his story behind the pictures.

Thomas Jundt is an engineer by trade, living in Switzerland, and has been sailing an 18ft Skiff on Lake Geneva with his crew for the best part of 15 years. Originally he was a 505 sailor but work commitments left him with little time to compete at an international level. Jundt says they were looking for a boat which would still be fun and exciting even in the light winds often prevalent on the lake and would also give them a challenge. “We bought an 18 footer because we do not have enough money to buy a big silly boat to sail,” he admits.

However, the problem with buying a boat to give you a challenge is, it becomes significantly less challenging over time. After 15 years of sailing the 18ft Skiff Jundt and his crew were beginning to get itchy feet and yearned for something to challenge them again. The options they were faced with were to either buy a new, different boat - which could be very expensive or start racing the 18 on the international circuit – which would take up too much time.

This decision making was going on about three years ago just, as it happens, when foiling Moths were beginning to receive some more serious media coverage. “I was reading a magazine and in there I saw the first developments of the foiling Moth sailing and straight away I though I really had to do this for the 18 footer,” explains Jundt.

Clearly this is easier said than done, as retrofit foils for an 18 are not something you can just buy off the shelf. Or can you? “What actually happened was I sent John Illet – of Fastacraft foils fame - a mail saying I would like to buy one of his foiling Moths in order to learn to fly with it. I said to him I then wanted to copy the idea and extrapolate it for an 18. A week later he mailed me back and said maybe we can do it together. So, we started to talk about it and then a week or so after that he said ‘I think I can build you a set of foils’. We agreed on a price and that was that,” says Jundt.

In reality due to the large amount of orders for Moths Illet was taking, there was a significant delay in getting the 18 foils ready for use. He was so busy, in fact, that Jundt suggests he probably did much of the work for the 18ft Skiff foils in the evenings and at lunch breaks. However, after six months Jundt received the phone call he had been waiting for. “In January this year he called me and said the moulds are finished so we can start producing the foils,” he recalls. Following the manufacturing and finishing process Jundt was finally able to get his hands on the foils in late July when they were delivered from Australia. It then took him all of August to fit the foils to his boat and sort out all the mechanisms before the team went for their first sail at the beginning of September.

Their first time out in the boat with foils on was an interesting affair and was not exactly what one might call sailing. “We wanted to see what sort of speed we would need to reach to get up on the foils. To do this easily we got a powerboat to tow us without the rig on,” explains Jundt. “We soon realised between eight and nine knots of hull speed was enough for us to take off.” The second time the team took to the water it was with the whole kit and caboodle. “We put on the rig and the sails, sheeted in and we flew.”.



See the first outing video here.

Of course with new developments it is never a case of just jumping in the boat and it working perfectly from the off. We have seen the Moth fleet spend several years perfecting their designs to be as efficient as possible and they are still evolving. The foiling 18 is no different and though Jundt and his team were surprised by how well it worked out of the box, so to speak, there are still a number of refinements to be made. “Basically everything works well, the concept is good but we do need to make some changes. Currently we do not have enough lift in the rudder so we always fly with the bow up,” says Jundt. Aside from the obvious balance issues involved in flying ‘bow up’ like this there is also a significant drag issue. “At the moment when we fly the rudder flap is all the way down to give the maximum lift aft. Conversely the centreboard flap is all the way up to get rid of lift at the front, so it is not a good drag situation,” he continues. Thankfully, the problem with the rudder creating too little lift can be solved fairly easily. “The rudder is fixed by two rudder pins so we will simply put washers on the upper pin to tip the whole system back. This will give the foil on the rudder a much better angle of attack.”



See the video of the first sail here.

The team have now moved the rudder gantry a small amount and two days ago, Tuesday, headed out on the water for their fifth ever sail to see what difference it had made. “The four times we have been out before have been quite light and we have managed to fly with the spinnaker – more of a very flat cut gennaker or code zero, needed because of the apparent wind the boat generates - up consistently. Yesterday we went out for the first time in 15 knots with the fixed rudder and it was fantastic. We could fly upwind. When we sailed a good upwind angle we were at 13 knots. If we footed off a little bit we were rather quickly at 15 knots but maybe without enough height,” comments Jundt.

However, the rudder proved still not to be angled far enough so the team were experiencing many of the same problems. Ever optimistic Jundt was all the more excited by this, adding that this time it was better than last time, but they were still creating a great deal of drag from the rudder flaps being almost all the way up. Jundt believes when they remedy this problem and find the optimum angle for the rudder the boat will go much quicker.

Sadly it will be a short while before we are able to see if the changes to the rudder have made a big difference as the team will be repairing the boat for the next few weeks. “On Tuesday we had the gennaker up, doing 21 knots and we lifted up and then crashed back down and we ripped off the rudder gantry. We need to re-build the gantry completely now, but this time I will build it with two degrees more forward angle on it,” explains Jundt. Unlike many boat owners he is not upset too much by the damage done to his boat but rather accepts it as a fact of life. “I did the calculations for the rudder gantry and my dynamic load calculations were a bit low I think. I am more used to static loads..”



See the video of the team foiling downwind here.

With the most moveable parts the rudder is always going to be a problem area in foiling boats and true to form the problems with the rudder on the 18 do not just stop with the angle of the foil. Jundt says they did not realise how important tiny adjustments would be on the rudder flap. After the first few times out everything seemed to be fine but as soon as the boat reached 20 knots during their last sail it became apparent the twist grip adjustment on the tiller was nowhere near fine enough. “There is a little bit of slack in the twist grip on the tiller so when we twist it there is a moment of no response,” he explains. “The reason for the delay is because there is such great load on the rudder flap we put a brake on it to stop it twisting back as soon as you let go of the tiller.”

This delayed reaction has, according to Jundt, created some hairy moments on the boat. “In the windier weather we would be flying regularly but then when we picked up a little bit more wind or we bore off we could not prevent the boat coming out of the water. When it does that it is a lot like slipping on ice, there is no centreboard in the water anymore and the boat just slips out from under you and comes over to windward.” Rather worrying to say the least.

Beyond these teething problems Jundt is extremely enthusiastic about the concept and has clearly loved the few short sails they have had so far. What of the future though? Is this really an option for a wide variety of boats and classes? “I think in five years everyone will be foiling. I hear a lot of people against foiling in many classes but these are all people that have never flown on a foil boat. It is simply fantastic.”

For Jundt and his crew, at least, this is providing a fresh challenge for them to get their teeth into. “Now we have many years ahead of perfecting this new concept, it is great motivation,” he says. It seems the foil concept really will work on bigger boats and the thought of a fleet of foiling 18ft Skiffs is an exciting one. Although foils are currently banned by the class association rules if Jundt and his team continue to prove just how relatively simple it can be, a breakaway class or adoption by the class association must be a possibility down the line.

Do you believe that everyone will be foiling in five years time? What boat do you think will go for foils next? Send us your comments: yourviews@thedailysail.com