Offshoreonly.com - The pros of having steps in the hull

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The pros of having steps in the hull

What are the pro's of having steps in the hull?

Usually 10-15% faster with the same power

When Formula "stepped" the 382 they claimed about 5 mph more at the same RPM (cruise and WOT). It was true and some manufacturers saw even bigger gains.

Faster in flat water.

Padraig

Step hulls date way back something like 1920 or so., Hustler did them way back in the 80 s. but it seems that step hulls were hugely marketed around 1998 year models to about 2008 and were called all different names. AVS is one prime example.

With that said it does not seem like current advancement has taken place with stepped hulls and bottom designs. Prob the latest most talked about stepped hull change over from straight bottom was SEA VEE CC boats about 4 years ago. They seem to ride and handle very well.

Seems like other things added to the mix helps as well - current props and modern construction advancements and those materials. . Another good example of a boat that beny from all 3 would be the Cig top guns. -- modern construction / materials, , props and the change over from Straight V hull to steps.

Always wondered how much of the step technology is actual theory/design/testing.
Consider :
Step placement related to longitude C.G.
Step angle to hull bottom
Step angle to hull centerline
Step depth
Step quantity
Step separation in multiple step hull
So how many of these and additional variables did each hull design undergo knowing a new hull bottom is needed to test each and every individual change ? How much is simulation vs actual full scale in water data gathering ?

IMO no one has done anything as of within 10 years for new bottom design and or converting V hull straight bottoms to a new line up of stepped hulls except SEA VEE. I do know they put in alot of time in with it. I even talked to the designer of the bottom Robert K. in an airport waiting for our flights during that time of the build. Anyways here is some info

Pros, faster so better fuel economy at the same speeds.

Cons, you have to learn to drive them.

As opposed to a straight bottom which is often just point, shoot and then trim the drives up, stepped hulls don't need lots of trim. They run better at close to level trim. The step design provides the lift so the power can be directed to forward movement rather than lift. If you trim them up and attempt a high speed turn, some step hulls can spin. Stepped hulls are not dangerous but they respond differently to straight bottom hulls and you need to learn about the individual boat.

Certainly, some stepped hulls are easier and more forgiving to drive than others. If you're considering a specific hull, ask the question here, there's plenty of experience on OSO and you'll get great responses. It's not a new topic so if you do a few searches I'm sure you'll find a lot more good info too.

Stands to reason that steps are better or there wouldn't be so many new boats on the market using them. :)

RR

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Good for seavee. Most boat companies R&D on the customers dime.

Fascinating SeeVee flick.
Basically what they're saying is 'We've finally designed a safe stepped bottom hull'