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Andrews 50

1998 September 6

Racerr

Alan Andrews has given us a long string of race winners. I always look forward to reviewing his designs. They are meticulously detailed. Alan is the type of designer who will show up on the dock for the first race and insist on weighing each and every tool on board. "No socks. All else being equal, the crew without socks will win." Races are won with this type of detailed approach.

Alan's client for this 50-footer wanted a boat he could race in events up and down the coast of California and Mexico. The boat would go from Olympic courses in San Francisco Bay to downwind Mexico overnighters. This makes the design challenge for the designer a balancing act. Fifteen years ago the potent downwind boat was generally not competitive upwind and vice versa. The heavy-air threat did not have the power to win in light air. Fortunately, the difference in purpose-built racers has been narrowed dramatically due to developments in keel, rig, hull form and structures. That about covers the design spectrum. We have all gained from this through the trickle-down from the racing classes into cruising boats.

Let's take a look at this gorgeous hull. Note the subtle and attractive sweep to the sheer accentuated by the short ends. This hull is all sailing length. The half angle of entry (HAE) is 12.3 degrees, indicating an extremely fine entry. Remember that 20 years ago we considered 19 degrees to be fine. The prismatic is moderate; Alan says it's somewhere between .54 and .55. He doesn't want to divulge the location of the LCF (longitudinal center of flotation) or the LCB (longitudinal center of buoyancy). It's top secret (TS) at this time. I think we can safely assume from the location of the keel that LCB and LCF will be well aft. Note the distinct lack of rocker to the hull profile. The D/L of this design is 75.

Bulbed keels are back. "What comes around goes aground." Alan's fin is iron with a large lead bulb. The bulb has a delicious, organic-type shape based on Alan's Whitbread research. In this case the rudder planform appears greater than 50 percent of the keel fin planform area.

The rig is fractional. This has the advantage over masthead rigs in giving superior acceleration out of tacks. This is probably due to a far greater proportion of the total sail area (the mainsail) being closer to optimum trim right out of the tack. The fractional rig also has the advantage of allowing the mainsail to be depowered and powered up quickly. Headsails will be a blade-type 100-percent jib and a PHRF-friendly 155-percent genoa for the light-air, lumpy-sea powering requirements.

The SA/D of this rig, if you include the area gained through the generous roach (about an 8-inch overlap on backstay), would be 32.5. However, we still try to use I, J, E and P for sail area in our calculations; that way the SA/D is 31.85. Either way, this is a high-powered boat. We see so many boats now that have extended roaches that we may need to modify our approach to SA/Ds in future issues.

There's really no interior layout on this boat. Alan was not designing a cruising boat. There is nothing in this interior most of us would call privacy. There is no dining table. You would just have to nurse your cold slab of Spam in your lap. The berths are all pipe berths and are as soft as they look; with a 1-inch foam layer, they are hard as a rock. This is a racing boat. Work hard enough trying to generate boat speed and you will sleep anywhere.

Usually I fantasize about incredible golf shots. But if I wanted to fantasize about sailing, I think I would have fun imagining a cruise on a boat like this. I'd fantasize about 4-inch-thick foam cushions for sleeping, and nobody would ever pass me.