BRAVO, I say, old Browne. I say again... BRAVO. What PLUCK you have! You are hereby nominated for this years PLUCKED AWARD... for contributions to TWList's growing body of carefully archived boating knowledge using nothing more than keen observations... coupled with a disciplined mind, an insatiable quest for knowledge and, most importantly, a rigorous scientific method!!!! BRAVO, Paul Browne! I say... BRAVO! Okay, so feathers are out. What about adding scales to my hull so I can slither like a reptile and plane like a sport-fisher? There IS method to our madness. By God, what type of beast might we call this scaley 40,000 lb toad of mine? dick jurgensen Orion-2 KK-42 Richmond Hill, Ga ---------- > From: PBrowne900@aol.com > To: trawler-world-list@samurai.com > Subject: TWL: Duck Speed > Date: Sunday, September 26, 1999 6:35 PM > > In a message dated 99-09-23 14:20:36 EDT, you write: > > > If I chose to go the feathers route to increase my hull speed, would there > > be a down side? If so, what could I expect? > > Ahoy there Dick, > > A couple of the TWL scientific staff have suggested that the practical speed > of a trawler can be increased through the addition of feathers. I must admit > to feeling some degree of responsibility for this, having introduced the > subject of ducks to the list a while ago. So before you bought a ton of > feathers for your next bottom job, I thought I should double check. After > all, the essence of the scientific method is to verify a theory by > experiment. > > The first part of my work entailed a few dry dock (dry duck?) observations. > Tempting a threesome of mallards out of the pond with bread, I observed their > underwater lines. The main observation was that these ducks were a full > displacement design, definitely not semi-displacement or planing. The shape > of their little buttocks, sweeping in rounded lines to their pointed little > sterns, and their complete lack of squared-off transoms made that clear. > Placing a ruler on the ground, and observing them when they re-launched, > allowed me to estimate their waterline length with confidence. I put it at > 11 in, close to Don Dodds' original estimate of a foot. > > The second part of my work involved actual speed measurements. To do this, I > adjusted my sliding door so that the width from frame to frame was 68 inches, > exactly the same as the distance between two porch posts. In this way I > could sight along two parallel lines formed by the door frames and posts. I > would wait until a duck swam by, and time how long it took for him/her to > cover 68 inches. My objective was to observe their practical cruise speed. > I had no interest in their top speed. I wanted them in trawler mode. > > The wind was calm. The pond was smooth, no chop. I hunkered down and > waited. The cold, hard weight of my stop watch feel reassuring in my hand. > It took a bit of patience, but I got some good measurements. I timed four > ducks. All four were in trawler mode, not rushed, looking around and > enjoying themselves. They came in at 3.8, 3.9, 3.9, and 4.2 seconds. > > A bit of math shows that their speeds were 0.88, 0.86, 0.86, and 0.80 knots, > for an average of 0.85 knots. Taking a waterline length of 11 inches, the > theoretical hull speed for these ducks would be 1.28 knots. Disappointing > results indeed for fully feathered hulls! They were only cruising at 0.89 > times the square root of their LWL in feet. You can draw your own > conclusions, but I am feel obligated to suggest that the Dodds Postulation is > seriously flawed. > > Now some listees may think to themselves that perhaps old Browne doesn't have > enough to do, but consider the legal bills that George would face if a major > boat builder were to launch a new line of feathered trawlers based on list > advice, only to find that that advice was unsubstantiated. Besides, it was > raining on and off today - can't work on the boat. > > Scientifically yours, > > Paul Browne > Boatless in Tampa