I am not familiar with a code D but from this discussion it seems that it is a sail which can be mounted on a furler which has an effective range from a close reach (60 degrees) to running? How does it differ from a code zero? My LIM sail wardrobe would be mainsail (a given), a headsail which is able to go from zero to hero as in flying a handkerchief in strong wind up to 140% for light winds and an assymetrical which can be mounted on a furling system or snuffer for easy deployment short handed. Would the code D replace the assymetrical? Can one get away without a staysail or storm jib which would need to be mounted on another forestay and which would require one to leave the cockpit in treacherous conditions?
It seems a code D is exactly what you want in a LIM sail wardrobe, David.
It has been conceived as a blend of an asymmetrical spinnaker and a code 0. The luff of the sail is almost as straight as a code 0, so the sail can more easily be furled. But towards the leech the sail is shaped more like a spinnaker, for better downwind performance.
The straighter luff makes the sail more forgiving for the helmsman and more straightforward to trim. And with a pole it can even be used much further downwind than an asymmetric spinnaker.
I think Paulo already posted this diagram:
No doubt a code 0 will perform better upwind and an asymmetric spinnaker will be more fun on a beam reach. But the code D looks very much like the best of two worlds and probably makes perfect sense when you want to reduce the number of sails -and the costs
- especially with the focus on easy handling.
By the way, on the Océanis 37 such a sail might also be a good answer to your question about a bigger foretriangle since the 105% jib does very well upwind, except in very light airs.
I fully agree with Faster’s analysis about shrouds on the toerail. If the sailplan is adapted -powerful main, non or little overlapping jib, code sail(s)- it has many advantages.
The loads are transferred directly to the deck-hull-bulkhead joint, which is stronger and much cheaper than inboard designs with pullbars intruding the interior.
The rig is also better sustained laterally, with less tension on the shrouds and compression on the mast. Within the same safety margin mast and rig can therefore be made to lesser dimensions, which is again cheaper. And also lighter, which is very important for performance because every extra pound high up in the rig needs to be compensated by many more pounds down in the keel.
In my honest opinion, the only real drawback is the obstructive lower diagonal when you need to go to the foredeck.
With such a sailplan, I think there is no need any more for large, overlapping genoa. They give you a very hard job when tacking and are much less efficient on a modern, fractioned rig.
Any foresail gets more baggy with every turn on the furling drum, which is exactly what you do not want when the wind builds up. The bigger the sail, the baggier it gets, with less pointing and more heel as a result. The more you furl, the higher the sail comes with even more heel.
So there is no way to make a from zero to hero genoa. If you want the sail to fly in light winds, you need light sailcloth. It will not resist furling and certainly not in strong winds.
With a powerful mainsail and a non overlapping jib reefing the main is the first move, even the second. Afterwards I prefer not to furl the jib but just get rid of it by rolling it away at once and rig a staysail.
This means working on the foredeck, but if bad weather can be foreseen -which is mostly the case- most of the work can be done beforehand and the sail will only need to be released from its bag or lashings.
Then you get a foresail with a custom design for strong winds, flat shape and heavy cloth. It also brings the center of the sailplan down and backwards, which is exactly what you want in heavy conditions. It can also be fitted with a reef, certainly a hard job to take in when it gets that bad, but at that time any furling headsail would be of no use at all.
So in my honest opinion, LIM with a big mainsail means a jib, a code D and a staysail for security.