Mark, I agree with your assessment of
current design trends and the genesis, especially as relates to production cats that are moderately priced (which is, in fact, the type of boat I wanted to discuss). I guess what I was attempting to get at is whether all of these trends are, in fact, beneficial - particularly for a boat intended to be sailed offshore. To your list I would add the following (as distinguished from many of the earlier cruising catamaran designs):
19. plumb, or nearly plumb bows.
20. no full width bow pulpit
21. only netting between the hulls forward of the bridgedeck (no solid foredecks, or center walkways)
22. no, or minimal fiddles on counters/tables
23. no backstays
24.
single centerline mounted
windlass
25. high freeboard to
permit a flush
deck except for the bridgedeck accomodation.
26. fractional rigs with the preponderance of SA in the
mainsail.
27. wider
hull beam, and/or large knuckles/bridgedeck tunnel protrusioins to increase interior accomodation.
28. shorter bridgedecks
29. large sliding glass
companionway doors
30 higher CG due to increased bridgedeck clearance,
galley up and, in the case of the
Lagoon 44 etc., elevated
helm stations.
31. higher CE for the sailplan.
Let me start by saying that the increased BOA (or more significantly, centerline beam ) permits a greater SA, a higher CE for the sailplan and a higher CG while maintaining equivalent transverse stability (although the raised cockpit Lagoon 44 with its concurrently raised boom makes me wonder...). Neverhteless, the result is a boat that is faster while being equally resistant to
capsize.
Furthermore, the increased bridgedeck clearance and the shorter bridgedeck than on many of the older designs, reduces the tendancy to pound (again, being mindful of some South African designs that have had minimal bridgedeck clearance; and, of course, boats with large protrusions close to the waterline in the bridgedeck tunnel).
Of course, most NA's believe that bridgedeck clearance must increase in proportion to increases in beam (and many believe centerline beam/tunnel width is more relevant than LOA/LWL in determining the appropriate clearance). Furthermore, according to many naval architects, as the ratio of BOA to
LOA increases past a certain point, so does the risk of pitchpoling. Nevertheless, IMO the advantage here goes to the more
current designs, so long as they are not too extreme: the BOA:LOA ratio does not substantially exceed 1:2 and the CG of the vessel and the CE of the sailplan is not unnecessarily high.
Netting forward, rather than solid foredecks/walkways between netting; no full-width bow pulpit? Clearly the elimination of these reduces weight forward and accordingly, reduces the tendancy of many of the early cats to hobby-horse; it should also reduce the risk of pitchpoling, particularly if one were to bury the entire foredeck.
Yes, it is hard to beat a solid foredeck for lounging (although that is not as significant in a boat intended to go offshore). Furthermore, although a solid foredeck provides a sure footing for retrieving anchors, repairing jammed furlers etc., the same can be said of netting divided by a solid walkway to the seagull striker/furling
gear.
Personally, I believe that the latter is the ideal compromise between reduced weight forward/reduced risk of pitchpoling and a sure footing for
repairs of jammed
furling etc. (admittedly rare, but when it happens it tends to happen in bad conditions). As to full-width bow pulpits - IMO while they have a deleterious effect on the lines of a boat, the added
security forward for repairs/spinnaker sets more than makes up for that and the minimal increase in weight at an extremity of the boat.
Galley up, versus galley down? IMO, in this area the advantage goes to the earlier design tendancy towards a galley down -
for a boat that is intended to sail offshore.
Yes, placing the weight of the heaviest part of the accomdation (and the heaviest stores) down increases the transverse stability of the boat. More significantly, IMO, that location provides a more secure setting for the cook (and the motion in cats, as we all know, can be fairly substantial in boisterous conditions). Furtherthermore, especially in cats under about 45 feet, there tends to be mcuh more
storage space available in a galley down. Finally, in my experience, the inclusion of a galley up, especially in cats of about 40 feet or less, tends to reduce the space available for a chart table/nav station (or the seating in the main
saloon - something has to give).
The absence of fiddles on counters/tables? Inexcusable, in my opinion, in any offshore boat. No, they do not have to be as high as in a
monohull (for obvious reasons), but they should at least be able to stop knives and plates sliding off a counter or table when underway in heavy seas.
The modern trend in rigs? Here I am of mixed emotion. My Sunstream 40 has a
cutter rig with a forestay, a staysaill stay, twin backstays and the aft shrouds further forward than in most current rigs. Due to the backstays it has only moderate roach, Since the
mast is stepped at the
companionway bulkhead, all lines are led to the cockpit without the need for turning blocks, etc.
As an offshore rig I believe it has significant advantages:
Firstly, the dedicated
furling staysail is a suitable storm sail and is cut with a high foot and made out of heavy weight (9.5 oz.) dacron. In storm conditions I can simply furl up the headsail and proceed without worries about going to the foredeck to set a galerider, or equivalent over the furled, lighter weight
genoa. As the
wind picks up, I can reef it even more if necessary and the sheeting angles, already appropriate for a relatively small staysail, can be readily adjusted to accomodate an even smaller sail.
Furthermore, the storm sail is mounted further inboard, as it should be and the
sheets are pre-rigged (unlike a galerider). Yes, you can attempt to reef your headsail for use as a storm sail, but the lighter weight material that is suitable for such a sail makes it much more likely to blow out, or at least stretch out of shape. Furthermore, in doing that it is almost impossible to get the appropriate sheeting angles to flatten a small triangle at the very front of the boat.
The smaller roach on the main and the fact that the aft shrouds are mounted further forward than is possible without backstays creates two advantages: firstly, the main can be let out further without interfering with the shrouds (good for durability, sail trim off the
wind and in reducing the risk of accidental gybes); secondly, sails with smaller roaches tend to have a better shape when reefed.
The disadvantages? Upwind performance is compromised to some extent by this lower aspect ratio rig and, nothing can beat a flat top for reaching. In my boat's current
environment (Lake Ontario) I must say that I would prefer the performance advantages of current-style rig. However, for offshore (or even for sailing in strong trades/Christmas winds), I believe that the catamaran
cutter rig still has much to offer.
Other aspects of the design/construction of an older design like mine versus the current trends are also a mixed bag. I prefer the lower freeboard on my boat for ease of boarding as well as reduced windage (and she tacks very easily); on the other hand, I despise the tiered 'xmas tree' appearance that it results in, even though it makes climbing to the top of the coachouse easy. I love the tempered glass fixed
portlights (strong and permanent), but I wish I had louvers or a brow to produce shade on the forward fixed ports/hatches.
I love the fact that I have watertight
collision compartments fore
and aft and that I can perform
maintenance on the diesels in a dry
environment (below decks), without risk of losing tools/parts/fasteners and while seated comfortably on in the inside curvature of the hull. On the other hand, I hate the increased interior
noise and the need to remove a berth cushion in order to get access.
I have my own opinion about plumb bows and floating furniture, but I'll leave that for another time.
Brad
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