View Full Version : Planing Help for a 2 point Hydro, "Hornet" from Ed Monks book

Christopher R. Jasinski
07-17-2001, 07:00 AM
Maybe I posted this wrong at first. There is already a message posted under Misc. section of this site. I wish to know if anybody has built the hornet and what luck they have had with it. My boat seems to be porposing at the rear step. does anyone have any ideas as how to stop this problem?

07-17-2001, 10:25 AM
Though I read Monks book years ago, can't remember what the hornet looks like. Never-the-less, the easiest way to reduce the chance of porposing is to move weight aft.

If moving weight aft works but you don't want to alter the boat in this fashion, another way of reducing porposing is to artificially move the center of hydrodynamic pressure forward by adding a transom wedge. The wedge depresses the bow, thus moving the center of pressure forward. (The center of gravity is thus further aft.) This also adds drag and slows the boat somewhat, but not as much as porposing.

The thickness of the wedge depends on speed of the boat and amount of bow down trim you need to induce. If you over do it, you will have control problems in following seas or even in flat water. I usually start with 1/2" thick at the transom, tapering to zero 6" forward of the transom. This is always too much. I then alternatly try the boat and plane off some of the wedge until the trim is to my liking. All the wedges I have installed have ended up 1/8" to 3/8" thick. However the exact thickness depends on the severity of the trim problem.

If moving weight aft does not eliminate porposing, the transom wedge will not help you either.

07-17-2001, 12:17 PM
You could try anti-porpoising plates that bolt to the outboard. Available at most marine stores.