Howling Boats

The back edge of one or both of your foils is vibrating.
Try sanding to a finer point if your class rules allow it, should make it go away

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Jamie600 Send Private Message Find Member's Posts Really should get out more Joined: 14 Jun 05 Online Status: Offline Posts: 718	Post Options Post Reply Quote Jamie600 Report Post Quote Reply Topic: Howling Boats Posted: 05 Oct 06 at 3:37pm
	The back edge of one or both of your foils is vibrating. Try sanding to a finer point if your class rules allow it, should make it go away

furtive Send Private Message Find Member's Posts Posting king Joined: 30 Mar 05 Online Status: Offline Posts: 188	Post Options Post Reply Quote furtive Report Post Quote Reply Posted: 05 Oct 06 at 3:34pm
	On Laser 4000s, this is caused by having a big fat trailing edge on the daggerboard (and rudder). Class rules allow you to sand down the back 75mm of both foils to make the trailing edge finer. This stops the high speed humming, presumably saving a bit of lost energy, but does make your foils a bit more fragile - be careful of the trailing edge if you capsize and are standing on the board. Foils made in the same way (ie other Laser boats) probably have similar issues, and also probably have the same allowance in the class rules as they all originiated in the same place. More hi-tech foils are probably designed/made to avoid this problem in the first place!

Black no sugar Send Private Message Find Member's Posts Visit Member's Homepage Really should get out more Joined: 04 Dec 04 Location: Somewhere between Brighton and Lancing Online Status: Offline Posts: 3941	Post Options Post Reply Quote Black no sugar Report Post Quote Reply Posted: 05 Oct 06 at 3:26pm
	Laser4000s sing in a variety of pitches depending on the wind and the crew. Having one of those screeching things appearing out of nowhere when you're in a Topper in a force 6 is an experience to remember!
	Lancing SC

NickA Send Private Message Find Member's Posts Really should get out more Joined: 30 Mar 05 Location: United Kingdom Online Status: Offline Posts: 784	Post Options Post Reply Quote NickA Report Post Quote Reply Posted: 05 Oct 06 at 2:42pm
	My lovely new boat howls when it planes. When it really gets going a second pitch kicks in and it howls in harmony. An F18 cat I once knew was so loud you could hear it take off from the club house! I quite like it ... but it's probably going to be really annoying to everyone else, plus all that noise must be robbing energy. Anyone else had this "feature" and cured it?