cosmic12

That is just to funny I have heard that before (shingles) from a person very close to Harry S. Every time a certian brand was mentioned. Just to funny.

pierre_l

in my knowledge in the performance boat category, the first was the monte carlo offshorer 27 and then 30.

created by carlo riva after he sold his yard. He was helped by Bob Hopps and Cal Connell.

LAriverratt

so the steps on v's today are just a sales gemic???

T2x

I have no idea what a "gemic" is. If you are referring to a "gimmick", then my answer is....in most cases yes. Certainly many boat manufacturers followed others in a "monkey see, monkey do" revolution about 10 -12 years ago. I agree that steps increase efficiency and speed when the hull is "wet" beyond the distance from the transom to the step. If properly designed there is no doubt that introducing cavitation on the running surface will reduce friction and drag. That having been said a properly balanced non stepped, pad hull will eventually run on minimal wetted surface and exceed the speed where a step hull works. You must remember that once a step is out of the water it has no benefit whatsoever. The problem is that even in slower hulls that do find gains from adding steps, there is a price to pay in handling and safety , especially in turns, that, to me, is not worth the modest and sometimes minimal gains in straight line performance. As a long time boat racer, I value tractability and balance above any other handling attributes, so I would skip steps (and counter rotating props) in favor of predictability in almost every situation.

T2x

scarabman

iTrader: (1)

Can you further define this? Do you mean opposite rotation on separate drives, or do you mean on duo-prop drives? What is the reasoning?

T2x

I mean "spinning in"........ wherein the rotational torque of each propeller creates additional outward leverage on the hull increasing the tendency to chine walk (and, in some instances, to barrel roll).

This is simple physics that some "experts" ( who should know better) routinely choose to ignore.....until they get wet.

LAriverratt

forgive me for my spelling...not one of my strong suits..just wanted an explanation on your view of stepped hulls on V's...good info to ponder... I do see your point. I'm not an engineer but I did play the part once at bar

T2x

Funny...... I think I played the part of a Gynecologist at the same bar.

glassdave

iTrader: (1)

interesting info, is this affect amplified on or unique to step hulls? So rotating props out on a V hull can increase instability? Correct me if im wrong but it has the opposite affect on a cat, that being spinning props in can increase tendency to loose control. I have kept a quiet tally of accidents I've witnessed and in nearly all cats they were spinning props in. It also seems to me that this instability shows itself most when control is most needed, when running close to the edge. I know when we get the big green boat out of shape on the race course if i keep the heat on she settles right down, we have always spun props out. Rich i thought i had heard at one time there was some talk of making spinning props in (on cats) illegal, any thoughts?

kap328

Mike G:

You have 40 posts in this thread and no one has answered the question. A lot of collateral banter but no one has been able to answered the question posed.

I am beginning to realize it might be a Gordian Knot for the boating masses.

A quick conclusion might be most online boaters only resort to the internet for their quick research and the answer to your question is probably in hard bound media in some archive waiting to be discovered.

Honestly, I would like to know the answer to your question and the history behind the idea.

KAP

P.S. A stepped V-Bottom rides and handles a lot nicer than a non-stepped V-Bottom in rougher water i.e...ocean. I do not think I would own a non-stepped boat for offshore purposes.

Note: Very interesting question you posed I doubt you will find the answer on a public boating forum. It would also be great material for a book i.e..."The Evolution of the V-Bottom."