NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Speed and waterline length. was: Revisiting hull pressure wave
From: Jared Sherman
Date: 2005 Jan 27, 12:50 -0500
From: Jared Sherman
Date: 2005 Jan 27, 12:50 -0500
Bill, I would expect your "downward pressure wave" is the same as the "ground effect" which gives aircraft extra apparent lift when they are about to land. And for that matter, when two boats under way come alongside, there's a point where the water between them also seems to help buffer them apart. In every instance you're seeing a point where the fluid (water or air) simply isn't being displaced but is being forced back by another object (the runway, the bottom, the other craft) and the flow is changing.
