High Flying Hydros

[blueskyracer]

Ok I have learned that a boat glued to the water is very stable but not fast. It is hard to get a boat like this to free up and fly over the water. Now for my question. If a boat is too free and is scary lose what are the best ways to get such a boat to settle down to within reason so that it is fast but will stay on the water and not be an airplane.

[Jim McKean]

Is it a Airplane, or Hydro: 130 mph bt Sean McKean

Hi Montoya Guys:

Look at this picture, with clearly only the propeller in the water. It is set-up, set-up. and set-up!

Jim McKean......."captainjimmckean@yahoo.com"

[Sonny]

Hey there Mike, I was under the impression that lift as well as setup "unglued" a boat from the water and afterplane (the length from the back of the sponson to the end of the planing surface) made it safe at speeds. I have noticed that the safe operating speed is based on this length. But it will be interesting to see what others have to say.

[blueskyracer]

Jim, Those are records and record runs but I am talking about all conditions and very seldom do we have glass smooth days for circle racing plus you have chop from other boats. I also mean that the boat is built and it is what it is. Working with what you have and trying to get it back to a safe point.

Do you give it more kick in on the motor and add lead to the nose, etc? I guess there is a point where to loose on the water is equal to going over backwards, not desirable. In a kneeler you can move forward but in laydowns there is no movement avaliable.

[Sonny]

Mike brings up a good point. I have a few boats that have a narrower bottom and pound through the sloppy water and I have a few that have a wide bottom that absolutely will not march through boat traffic safely. compounding this I have motors that will not work on the boats with skinnier planing surfaces. So it would seem like there is a fine line between motor weight vs. condition friendly setups.

[pops67g]

Could be simple, might not be....

Handling problems can manifest themselves in a lot of ways. When you test change only one thing at a time. Loose doesn't have to be out of control, it can be fast as well. It depends on your definition of "loose". Some propellors can hurt stability and some can enhance it. For example, I have a low rake 3-blade cleaver that can be really fast but it makes me hold my breath way too often. I put my low rake 4-blade on and it is equally fast but much more solid and driver friendly. This is at the same exact height and tuck. Adding weight to try to fix handling is generally a poor idea.

[modracer7b]

My thoughts also about what you consider loose. Is it blow-over loose or back-end loose. Makes a lot of difference in the approach to control it. Also, has this been a problem since the boat was built or did this start with a change in equipment or when reaching a certain speed range.

Bill Rosado

[blueskyracer]

This is just in general for any boat that might be very close to blow over when a breeze comes up or the water is a little rough.

Folks have told me it is easy to calm down a flighty boat but never said how to do it. They always said it is much harder to loosen up a boat that sticks to the water.

[blueskyracer]

Ok bottom line the new "step by step build of the D Mod" boat has a lot of changes. If these changes are a little to much I am trying to find out how to settle it down if necessary. The bottom lift has been increased, the break point has been moved back a little, the tunnel has been increased and the cockpit is now offset. All these changes are not drastic but enough and this is a laydown.

Trying very hard to be competitive with a kneeler is the goal.

[pops67g]

It's about design speed

The best success in racing is when the vehicle, in this case a boat, is designed specifically for a certain class. Outsiders (non-boat racers) think that to go faster you put the biggest engine on the smallest boat possible. My DSH is about 11' long and runs 80mph or so. A good CSH is maybe around 10'. Only a foot different, so can you put the D motor on the 10 footer and go faster? I value my hide enough to never try it! Obviously there is more to it than just the length but I hope people see the point. If it consistently flies too scary high maybe it just needs to run slower.

[David Weaver]

Balance

Finding the right balance of lift, afterplane, COG, etc. It just takes testing and experimenting. With this Pugh, the key ingredients are a little extra afterplane and 4/5 blade propellers. The 3 bladers created too much lift.

[Wayne mtl qc]

Taking some air Out

Mike my good friend Jeff Brewster was having the same type problem fast as hell but to loose and hard to handle in poor conditions.He found a trick to overcome this problem and I've seen first hand just how much control he put back into the boat when he needs it .I will call him and ask him to post or let you know what he did as it is his idea to tell if he wishes.

[modracer7b]

My cures for the blowover problem assuming it can't be cured with engine tilt or different style propellers are an add-on to the afterplane length or by trapping less air in the front and middle and more air out through the back. That is shorter traps behind the sponsons and deeper traps at the back of the boat to essentially drive the front down. Moving the transom forward can have a positive effect on this issue also.

Bill Rosado

[David Weaver]

Do you give it more kick in on the motor and add lead to the nose, etc? I guess there is a point where to loose on the water is equal to going over backwards, not desirable. In a kneeler you can move forward but in laydowns there is no movement avaliable.

Not much movement forward, but a little. I can move forward if I have to.

Sounds like you have a condition of trapping too much air. Is the boat walking in the direction of the prop rotation? You can always drop the engine down a little.

[blueskyracer]

Well the first test session for the new D mod is the last weekend of April and I will keep all these ideas in mind. Who knows it maybe perfect right out of the box. Wishfull think but it helps. Just want to kind of figure out the next step if it is to flighty. Like somone else said landing on the head is not desired and to be avoided if posssible.