PT 45 wants to fly !!

[Gary]

Need some opinions on my Phil Thomas Supersport 45 Hydro. Boat has performed flawlessly since day one and I couldnt be happier and would just keep pushing it until i found its limit! But..........now she wants to fly at anything over 88 mph and boat is completly out of the water except for the prop. Here is my question... I allready angeled the front canards as much as I dared and added a little wieght when I built it so at this point what would be best? Add more wieght or put an extension onto the canards for more downforce. I would think more down force is just like adding more wieght and the boat would think it is more heavy up front than it actually is at speed...No?

[carlcisneros]

Here's what can be done to help out with the flying problem.
Get you a cheap windshield wiper blade. cut it to the length that is needed to be mounted UNDER the hull between the the center section and the insides of the sponsons aprox. 1 1/2"
back from the leading edge of the front leading edge of the main airfoil section at the front of
the boat. glue them into place.

These disrupt the air flow under the hull and help to prevent the hull from trying to take off
and fly.

Hope I made sence here.

I have done ths on a few 1/8 scale boats and a couple PT boats and it does work.

Carl
and at 88 MPH, you are really HAULING FREIGHT buddy !!!!!!!!!!! :-)

p.s. you can also e-mail Phil Thomas and he can set you up with a kit for that if it is still available.

[Fluid]

Some hulls simply will not go faster than the "hull speed" no matter what you do. Phil designed this boat to go 45-50 mph, it has plenty of lift to balance a nitro setup at that speed. An under hull spoiler has been used for decades to reduce a hydro's lift, and the front canards on the PT45 have been lengthened and angled down to increase downforce. The 'kit' was for earlier hulls versions, newer ones have the improvements already.

88 mph is great, to go very much faster for any distance you may need a different hull. It takes more than just power to go real fast.


.

[Gary]

Thanks for the input guys. Its amazeing how this.....or all hulls can be a perfect running boat untill it reaches a speed it can no longer tolerate. I may just drop one prop size and leave it at that or try th air dam.The chase for speed is what makes it fun to go back and forth to the lake and i hate to just stare at it on the shelf with no modes to make LOL !! I did contact Phil Thomas and he was thrilled and laughing at how fast It was going and said us Electric Guys where all nuts!!!!!!!! Good times!

[carlcisneros]

here is one other thing you can try:

draw yourself and air foil on paper.
you know, flat bottom with a nice curved top section.
(you can google Clark-Y airfoil and that is what you will be drawing)

at the HIGH point of the top of the airfoil section just DRAW a little circle.
that little circle you drew and disrupt the air flow going over the top of the
airfoil and reduce the lift a bit.

this can be duplicated on the actual hull using (believe it or not) fuel tubing
taped down to the hull.

just cut the tubing to the length required to go across the high point on the boat
and then tape it down (completely covering the tubing) to the hull.

This type of procedure does work on aircraft and it just might work on the PT.
and if it does NOT work, then remove the tape and tubing and you're done.

Carl

[JMSCARD]

One way to try that i have used is to cut a piece of thick cardboard 1/2" shorter then the length between your sponsons... cut the cardboard about a 1/2 to 3/4" wide..... take a piece of duck tape and cut it the exact length between your sponsons.... put the piece of cardboard directly in the middle of the duck tape and it will be sealed inside the duck tape.... then with the remaining duck tape around the edges stick the cardboard between your sponsons of course... works great.... I've done this and it is easy to take off if you decide to go slower again :) do you get where I am coming from?

[Doby]

Poor Gary;

His boat gets airborne at 88 Mph.............poor Gary.........

Would you be upset if it got airborne at 188 Mph? Or would that be fast enough for you to be satisfied?

Poor Gary..............only can get to 88 Mph.......poor Gary..........

[Gary]

............. "A Fast Electric boat to run, the sky's the limit" ....right?

[carlcisneros]

Oh gawd!!!!!!!!!

Lol

[Doby]

............. "A Fast Electric boat to run, the sky's the limit" ....right?

True....

[Flying Scotsman]

88 mph!!! Damn it, that is fast for that hull...I would be a happy camper, the airborne antics I would not like

Douggie