After posting some pictures online of a new jib-sheeting set up on my Etchells, I received a question from Hendrik Visser, who hails from the Pittwater area, north of Sydney.
Question -
Your new jib-track set-up is exciting. I presume you have a jib cut for purpose? I was experimenting with inboard jib sheeting in 1978 worlds off Palm Beach (Sydney) sailing with Dad and Sir James Hardy. We finished 5th. Broken boom in last race wiped us off the podium.
The inboard jib worked really well in dead light conditions offshore. Was higher and faster.
Why I stopped?
It only worked in those conditions probably because of jib shape at the time
Nowadays they tend to abandon races in those conditions
Be interested in your thoughts on jib shape for this innovation.
Answer -
I have been thinking about your question regarding the "in-hauling" of the jib and thus narrowing the angle of attack. I love the circular nature of how we endeavour to make boats go fast. To hear that you experimented with this 42 years ago is pretty cool. In my experience nothing is really new in an established class like the Etchells (or Star, or 5.5 or Dragon). Sometimes an idea was good, but it didn't work because it was not done in concert with other things.
The jib shape for aggressively in-hauling the Jib does need to be different if it is going to work consistently. Note the change in sheeting angle on the drone photo. Our sheeting angle for many years (where the fore-aft tracks were alongside the cuddy) was approx 10.5 degrees. The sails are now being sheeted so the jib-lead is approx 100mm inside of the corner of the cuddy, which is approx 7.5 degrees. Clearly a significant difference.
The sails proven to have worked best for closer sheeting angles to this point are not surprisingly designs that do not have as much "return" in the lower part of the sail.
For example, the successful and popular LM2L design from North Sail's carries it's depth all the way to the deck (as is typical for a light-air sail). For this reason, it's success as an "in-hauled" sail has limitations. I used this sail for many years when campaigning with Tom Carruthers (San Diego). We in-hauled quite a lot for that time, but we found we had to be very careful about being in-hauled in waves or when trying to accelerate. But when we were up to speed and in relatively flat water, in-hauling was indeed a weapon. Although, we were not doing it quite to the extent as today.
Jud Smith's Doyle Sails jibs generally have less return in the bottom part of the sail and lend themselves to in-hauling. I coached at the 2013-14 Winter Series in Miami. That winter, Peter Duncan (with Jud crewing) dominated the series. They had an extra set of fore-aft jib-tracks fitted on top of the cuddy and were in-hauling quite aggressively for that time. They were also sailing with the mast raked a long way aft. They were potently fast. That really set the fleet on the road to testing "how far in is too far?". And I am not sure yet if we have answered that question.
The new Australian designs from North Sails (the MAL and the GT), both come from the "GM family", which as you may know is an old heavy-air design from North Sails Australia. The GM was always a lovely looking jib, in terms of depth, twist, vertical camber and versatility with different battens etc etc... It's genesis as a flatter-backed, cleaner exit down low and low-drag shape does lend itself to a closer sheeting angle. See the picture here with comparative analysis of the North MAL jib and the Doyle MHL jib. These were taken a couple of weeks back in 11 knots and flat water on the Solent. Both sails are lighter-wind designs. As you can see, there is very little between them.
As you know, we need to keep the big picture in mind. To just in-haul the jib alone will likely not give a positive result.
What I see out there on the race track when racing or coaching is that the faster boats are sheeting the mainsails firmer and generally flatter in any conditions than what we were a decade ago. The resultant shape is shifting the centre effort aft in the sail-plan, so I see the tighter sheeting angle of the jib helping to balance that. The mainsheet traveller is also employed as a more dynamic trimming tool (higher and lower than what our previous extremes were).
The resultant firmer headstay from this mainsail set-up sees the more recent jib designs with a little less hollow designed into the luff of the sail to retain entry angle and to power them up a little.
But in general, to retain balance, the in-hauling of the jib is a key ingredient.
Finally, keep in mind that sheeting the jib in as far as 7.5 degrees and sheeting the main firmly will narrow your steering groove and will also make accelerating difficult. It also won't be great in fresh conditions. So choose your times to employ it.
It is very cool to see the venerable old Etchells class being sailed differently and at a very high level in the class's 52nd year!
Mate, I hope this helps and makes some sense.
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