Hull design - CAD drawings

Thats why you would have a motor on each side of the hull.

http://www.aeromarineresearch.com/tbdp6.html

Tunnel Boat Design Program software
About TBDP Version 7

http://www.seanews.com.tr/article/w...rowther--News-by-topic--Order--vessel--wins./

 

The forward foil would likely introduce a wake of turbulence which would render the aft foil ineffective. Perhaps a single foil slightly forward of your LCG, and use a trimable prop aft to provide overall trim control.

You might look at this system for ideas: http://www.hysucat.co.za/another_page.html

 

Hmm, back to the drawing board...... The idea, however, is to cruise at minimum speed to be on the foil, with this in mind and the distance between them is there any other configuration - 4 struts ? 3 maybe

 

Interesting, would the water be - that - aerated though if it was at low speeds on this hull ?

Thanks for the links

 

hull 2

I have submitted a redesign with a front foil that would displace the flow between the catamaran hulls in the "tunnel" with a wide foil at the back, would this work ? If, while foil borne it became a plane type hull this would still be a reduction in drag....I'm also wondering if this could be powered by impellors in the cat hulls at the rear like a jet ski

 

How will the height and attitude of the boat be controlled when foil-borne?

 

Those HYSWAC-thingy type boats, they are no different. No control when foil borne, they are passive.

 

Obviously it depends on how much lift the foils develop, in the case of the foil assisted cats you refer to, the whole weight of the boat isn't foil supported ever, when you have foils that project deeper under the hull, in theory it could be.

 

I was hoping it would sort of plane on the base of the cat hulls not really out of the water ? It's only intended for inland waters, rivers and fair weather and I was thinking the foils could be folded up....

 

Which ones are you referring to? The HYSWAS (MAPC's) and Navatech's HYSWAC were both entirely dependent on the active control of foil lift to acheive and maintain stable flight. Same as true of the foil-asssisted DAT we built...a control system hiccup underway meant an immediate plough-in.

 

Oops, looks like I confused HYSUCAT for HYSWAC !

 

See, so many acronyms to shake a stick at...there is always one that picks you up on it !!

The ones designed, in general, by the South Africans, such as Prof Hoppe, Teknicraft et al. Thiers are always passive.

 

That they usually are. A couple of them have been built with active trailing edge flaps in the main foil and active tabs or interceptors on the transom, they are the exception rather than the rule for that configuration.

 

What determines ride height/sinkage and pitch/trim at speed in the ones with passive controls?

 

Passive but adjustable. The aft fins can be set at different attitudes to adjust trim. Once set, they are fixed in place, so they probably only function optimally at a narrow speed range.

I've thought that trimable outboards might accomplish the same effect on a small boat, but could be adjusted dynamically.