I am in the process of modifying a 17' long, 8' beam relatively flat bottom (5 degrees at the transom) power boat by adding a cabin. I know this will increase windage considerably. Question is: Should I be adding a small skeg to help allievate any increase in leeway in a wind?
Any thoughts would be appreciated as to yes or no or to the size and depth of the skeg. This is a planing boat but I am not worried about high speed.
Thanks in advance.
A good question, A skeg won't hurt. No reason not too. How big is this cabin? How far forward? It must be something if you are worried about wind. I will look in my books to see if I can find a calculation for size... Hopefully we will get some additional responses on your question. -Kruez-
ReplyDeleteThanks for the quick response. Hopefully, you're correct and others will reply. The boat now presents about 51 sqft broadside to the wind. I will be close to doubling that to almost 100 sqft, so I am sure in a little wind, I will be gaining some unwanted leeway. The pros to me of a skeg, of course, is to resist the leeway and to add strenth to the hull. But since the hull doesn't need any more strength all I get is less leeway. But less leeway is good, leeway gets expensive in fuel comsumption if you have a long run and have to crab with the wind off your beam. Also, leeway is a major concern when docking or manuevering. The cons, and I'm sure there are more, is 1) additional wetted area and associated drag 2) an increase in draft and 3) possible interference with water flow to the engine, causing cavitation and 4) arguably easier to damage a flat bottom. Thanks again and I'm interested in any comments.
ReplyDeleteMany older boats (sail and power) have skegs with power props, I personally don't think that a skeg would provide much interference in the form of drag, excess power consumption, or interference in forward motion, and would definitely give better tracking... Andy
ReplyDelete