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Aerodyne 47

2002 February 6

Performance Cruiser

This is a very well-thought-out boat, and I really don't have the space here to do it justice, so if you find it interesting why don't you write for Aerodyne's substantial and informative promotional package. I'll focus on the elements of this Rodger Martin-Steve Koopman design that I find interesting. The idea behind this boat was an "ultimate cruising boat" for a couple. We could sure argue over the definition of ultimate, but let's just acknowledge that it's a very subjective term.

Aesthetically this is not a classically beautiful design. The ends are truncated, the sheer is flat and the transom goes on forever. Then again we don't see too many classically beautiful boats anymore. Just look at the boats in this month's reviews. Overhangs are a thing of the past. Every designer wants to maximize sailing length for a given LOA. While we can wax on about the contribution that overhangs make or do not make to sailing length there is no argument over the benefits of waterline length. The photos of the Aerodyne 47 show it to be a very handsome if not beautiful boat. I'm certain the owners of this boat will find it beautiful.

The 47 is moderately beamy with an L/B of 3.25, and the beam is carried aft. The bow does not appear to be very fine, at least not on deck, and that will help keep the boat dry. Fore and aft rocker is flat and the D/L is 152. We could have a long and drawn out argument over "ideal" D/Ls for cruising boats, but it all comes down to sailing style and individual approach. Heavier boats have their advantages as do lighter boats. In most conditions the lighter boat will be the faster boat while the heavier boat will be the most comfortable.

It takes a skilled builder with a dedicated approach to lightweight construction to produce an offshore cruising boat with a D/L as low as this one. The cruiser needs to balance weight against durability. Lightweight structures can be extremely strong, although strength and durability are not necessarily synonymous. The rudder is huge and the long fin has a bulb. Draft is only 6 feet. Martin likes nearly circular hull sections with a fairly narrow BWL.

The 47 is laid out for a couple with another couple as guests. It's a good layout with a huge galley and lots of counter space. Remember the cook is the most important crewmember. It's better to be lost and well fed than it is to know where you are and be hungry. You are going to be very comfortable on this boat.

The rig is unusual in that it combines a big main with the mast set well forward with a nonoverlapping, self-tacking jib on a Gary Hoyt-type jib club. This type of club is far better than other types of self-tending jib arrangements. With this club you don't need to vang the club or move sheet leads or adjust clew boards to maintain proper trim as you bear off. Of course, you do have this thing obstructing the foredeck, but I suppose you could swing it to one side when you are anchored or at the dock. It's not a pretty feature, but having a boat with this style of club myself, I can assure you that it is very efficient.

The promotional material goes to great lengths to prove the point that a moderate SA/D is better than either a low one or an overly ambitious higher number, and I would agree. It's great to have a big rig when everything is nice, but on a boat like the 47 you should be able to see at least 20 knots apparent before you are forced to reef. With the forward mast location of this design you can probably sail it effectively under main alone. A unique track system allows the self-tacking jib to be reefed while staying on the club. Drawings and photos show a loose-footed main and about 15 inches of roach overlap on the split backstay.

This deck style is the exact opposite of the deck on the C&C 99. This deck is all soft shapes and radii. This does reduce windage. The hard dodger covers about half the cockpit. Halyards are all led aft and the photos show sissy bars at the mast. There is deck access to the huge lazarette and forepeak areas. The self-tacking jib club wipes the deck clean of genoa tracks and associated gear. A short, pipe frame-type bowsprit gets the anchor away from the nearly plumb stem. The transom opens to the large swim step.