I did not like that my Lightning questions hijacked Catspaws thread so I've created this one so I can continue to pick the brain of DonKeyHoTey and others.
In the original thread, I volunteered my boat to CatsPaws and boldly proclaimed myself an expert. DonKeyHoTey was nice enough to ignore my hubris and offer some of his knowledge about racing the EC in a Lightning dinghy.
Here are the posts that discuss the Lightning:
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Comments for anyone considering a Lightning for doing the EC (some of this applies to other candidates as well):
I've seen a fair number of Lightnings on the beach at Ft De Soto (including my own 
, in which I've completed 3 ECs). All things considered, she is a very good boat for it (this confirmed by sage Sawhorse while discussing the subject).
Of course, any boat is a compromise. WIth the stock rig's sailplan and 26' mast, the Lightning is a handful for a soloer or even double-handed. OTOH, it is quite fast and stable thanks to its 130# steel centerboard, 6' beam, and hard chines.
In the event you actually capsize, you should be able to re-right the boat even solo PROVIDED you have cleated the c/b downhaul so it doesn't retract. I'd also have a masthead float so she can't turtle. Definitely doa capsize test of the Lightning or any other candidate boat, preferably in less-than-calm waters. Note that if you swamp, the c/b trunk's cap may be submerged, making it virtually impossible to dewater the boat. It's possible that additional buoyancy can address this, but then she may float higher when on her side, which can make her more prone to turtling or harder to right and/or reboard. Placement of any additional buoyancy is important. Test it.
Note that the c/b draws 5' fully extended. Entering Stump Pass, approaching/leaving Chokoloskee, and crossing Florida Bay all require the ability to potentially sail close-hauled in, say, 2' of water. Raising the board to allow for that, the boat has huge lee helm and simply won't point.
Another factor to consider is that the boat was designed as a lake sailor and has low freeboard.. she's wet, and surfing in the big stuff will redline your heart rate from fear of stuffing the bow.
Make sure your rudder is not only sturdy but big enough that you have positive control in all conditions. A cassette rudder is a very good solution provided it is big and sturdy enough (I added a third pintle/gudgeon to my cassette-type rudder at the bottom of my cassette and skeg). A boat or other system is only as strong as its weakest link....Rudder failure is probably the primary reason for sailboat dropouts in the EC. I've had two failures in the EC -- one of which was a show-stopper, and the other would have been if not for a spare rudder.
Three other points:
1) Please don't do the EC alone in a Lightning or pretty much any other boat of that size/complexity until you are a very experienced sailor.
2) The Lightning weighs >800# on the beach in EC trim ~ you gotta be able to get her off the beach.
3) She's definitely not a sail&oar boat.
DKHT
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DonKeyHoTey,
I didn't think about needing to oversize the rudder to maintain control. Now I'm worried.
I built my rudder foil so that when it is fully lowered it has approximately the same area as a stock Lightning rudder. I was hoping my high aspect 0010 NACA profile would be more efficient than a Lightning rudder and give me enough control even when not fully lowered. This seems to be the case as the boat sails fine with only half the blade inserted.
At max insertion my foil would have 28" inches of the 11" chord in the water stream.
Does this seem adequate to you?
What conditions do you feel would require a larger rudder? Maybe I need a wider foil so I'll have plenty of surface area when trying to sail in shallow water.
My biggest problem, at the moment, is balancing the sails when the main is reefed. When I reef the main, especially on the second reef, the boat has terrible lee helm if I fly the jib. I guess I need a reefing jib or a smaller jib to use when the main is shortened. Your recomendations would be greatly appreciated.
Thanks for all your tips on sailing a Lightning in the EC. I've been worried about the boat turning turtle. However, my repeated capsize tests (all in calm conditions) don't show the boat trying to go that way. The mast is filled with styrofoam and although that little bit of foam doesn't look volumous enough to be helpful, maybe it is adequate.
I've added quite a bit of additional floation and the boat floats on its side with the centerboard truck a good foot out of the water. But when righted, the water is only about six inches from the top of the trunk. Again, I've yet to test in rough conditions.
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Ahoy Tigger. The slower we're moving, the less effective foils like our rudders become. But it's usually not a problem for rudders because there aren't big forces that need to be managed or overcome.
But at high speeds (high winds) with a lot of sail up -- such as the full Lightning mains'l, the rudder may see big inputs and therefore big loads -- particularly if surfing in big seas. And there's the potential of the rudder ventilating if a wave passes under the midships and lifts the transom out of the water. The result is less rudder efficiency, which means bigger rudder angles to achieve the necessary course change -- and therefore increased potential of it stalling..... Stalling at speed can snap the rudderfoil or break a gudgeon/pintle.
In shallow water, you'll almost certainly be restricted to your main alone, in order to avoid the lee helm problem you described. The CLR will have moved quite far aft due to the board needing to be almost fully retracted, and the CE will need to be pretty close. So with less sail up, less rudder will be needed. And the cassette-type rudder lets us keep it down until it finds the bottom, without risk of breakage, so more rudder is available if needed. One of the attractive shallow-water features of the Lightning is its hard chines which, if the boat is heeled, provide nice lateral resistance, making up for the smaller and less efficient swept-back c/b. And heeling the boat gives her more weather helm (or less lee helm). Moving weight fore and aft can also help with steering the boat.
My Lightning is cat-schooner rigged now, partly to make her handle better in the skinny stuff. But with the stock sloop rig, in heavy air with main reefed, I doused the stock jib and used a 420 jib on an inside set, using the topping lift and a tackline to a fitting on the foredeck, placed so that its luff was parallel with the forestay. The 420 jib is set flying, so when doused, there is no inside stay to interfere with the big jib. The 420 jib is half the size of the stock jib, so in heavy air, it's is much more manageable, particularly because it's set more inboard. With the main reefed, it also makes the boat balance very nicely
Re flotation, I'd place it on the centerline. If, for instance, you use the big yellow beach rollers for launching, and if your boat has an open forepeak (mine is sealed), I'd find a way to secure one (or two) up there. I'd secure the third on the centerline aft of the c/b trunk (this what I've done). By placing them on the centerline, they will not affect how your boat floats when on its side, but will provide considerable floatation when she's upright but full of water. Btw, each roller provides about 160# of buoyancy if I recollect correctly.
Hope this is helpful.
DKHT
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Tigger, I meant to respond to your question about rudder size. My original kickup rudder was just under 2sf (wetted). I thought it was too small in heavy conditions.
My current cassette-type rudder is 3sf wetted with the foil fully extended. This area is a combination of both the wetted part of the rudderstock which extends to the bottom of the skeg (where there is a third gudgeon/pintle), and the foil which draws about 2.5' max. I am very happy with this even though I don't need the full area much of the time, because it's the fraction of time when I DO need the full area that I'm most concerned about...
When the 60" foil is fully hoisted, it is in line with the bottom of the skeg and stock. Raised, the foil and stock are about 0.5sf wetted and provide a modicum of steerage.
Anyway, if you like your rudder, it ain't broke, and won't break, don't fix it..(but DO test it). Though you could probably pretty easily build a somewhat bigger foil that fits in your cassette...
DKHT
I have a whole new cassette-type rudderstock that makes it easy to remove the tiller. You may be able to do something similar. With the sloop rig, you could top up the boom by rigging a topping lift -- though you wouldn't be able to row-sail while topped up.
