V-Tail airboat
 

Hi guys. I've been working on a coroplast/foam/wood hybrid tunnel hull type of airboat. The hull is basically built, and I'm starting to work on the engine mount, etc. My question, if I angle dual rudders like a reverse v-tail on an airplane, would that improve handling characteristics? With each rudder on it's own servo, I would have pitch control both fore and aft (flaperon or speed brake function). I also thought about adding an elevator towards the front of the boat. While moveable, it would probably only be used to trim the boat for level driving. Any feedback on this design idea?

RE: V-Tail airboat
 

Although your idea might sound good , I question it , since basing my designs around all true ariboats , I have not seen what you are saying on any real airboats yet . ( not saying that your idea is not a good one )
The way that the true airboats gets better ride attitude and steering abilities is thru the shape designed rudder .
Whether it be the top of the rudder is wider for better control ( ride attitude in the turns ) or the bottom of section of the rudders being wider .
If you do indeed go with that design , PLEASE keep us posted on how it turns out .
Inquiring minds want to know ;)

http://home.mchsi.com/~terboinc/rudder.JPG

( please excuse the crude hand-drawn picture ... did it fast so I could post it here .

RE: V-Tail airboat
 

Thanks for the reply. I am new to the boat scheme of things, but some of my ideas have uncanny ways of working out. I think I'll go ahead with the plan, and yes, I will kepp ya'll posted on my triumph or failure.

RE: V-Tail airboat
 

TERBObob,

In your opinion, what effects does the rudder shape you described give over the standard barn door type (rectangular)?
Which type would be best suited for, say........oval racing?

Everything I've designed to date have been the barndoor type.

RE: V-Tail airboat
 

That would all depend on how your boat handles in the turns . If she nose dips , then you would need the rudder wider at bottom , but if she raises upwards and kind of does a skipping thingy , then the bottom of the rudder would need to wider( longer - whichever way you want to refer to it )
This info was all obtained thanks to the manufacturers of true airboats , and so far , it is does as was described to me .
A square "barndoor" style is prefectly fine as long as your boat handles as you want in the turns and when up on plane .

RE: V-Tail airboat
 

Thanks TURBO bob,
This reasoning corresponds with what we do with our inboard hulls. The difference is that instead of changing the shape of the rudder, you tilt the bottom of the rudder towards or away from the transom by means of a locking pivot point. Just a few degrees makes a huge difference.

This same technique 'may' possibly be applied to airboat rudders as well, to some degree. However I can see the benefit of the rudder shape being changed as having a bigger, more efficient effect. Any thoughts as far as proportions?

RE: V-Tail airboat
 

TERBObob,
I don't understand. If it nose dips in the turns it needs to be wider at the bottom, that's pretty clear.

Do you mean it's too wide, and needs to be narrower?

How about angling them in like an A. Having the tops closer together than the bottoms. I thought this might keep it flatter in the turns.

RE: V-Tail airboat
 

That's my idea with the v-tail. Exactly my thinking. And with a flaperon/spoileron function, it would be even better.

RE: V-Tail airboat
 

Deadeye are we on the same wavelength? I just found this site as I was poking around for rudder throw info. I have a tunnel ram with the angled "A" frame design nearing completion. I was wondering how far along are you and if you have managed to try this out yet. I buy your logic (cause it's mine too :o) ) and that the "twisting" moment of the angled rudders should help big time in turns.

Well if and when I complete this beast I was post all kinds of "dirty details" and pics[:-]..... that is unless she "bites the big one" then I'll just post that the design is flawed.
:D

RE: V-Tail airboat
 

So Gents ,
How far are we from conpletion so the rest of us can get all the gorey details of how this went ? Success , needs more adjustments , or total failure ?
New ideas are ALWAYS GREAT ... and when they pan out ... then they are SUPER !

RE: V-Tail airboat
 

From who???

RE: V-Tail airboat
 

Hummmm looks like a cliffhanger........ Will Terbobob get to speak his mind or are his rants and raves going to be blown away forever(pun intended) ? Stay tuned to this channel for the ongoing saga offffff........ Thinking Outside The Box!

.......Errr sorry folks sleeping with your head on the work bench using the boat for a pillow will do that to you. You've been warned!

Does drool cause warpage?

Servo question of the day
To gang or not to gang THAT is the question!

-Cold <----man does this dude need sleep!

RE: V-Tail airboat
 

Sleep is irrelavent............

What you describe is called devotion..............(or depravation):eek: