Deep V Hulls

Some people will tell you a flatter bottom is going to be more efficient. Well, there is no simple answer.

For example if the waters are choppy, then a flat or nearly flat bottom hull will have to reduce speed drastically due to the hull pounding and slamming, let alone the stresses put on the passengers getting their spines torn out thru the roof of their mouths, slamming up and down on their seats. Whereas with Deep V hulls, the ride is like a mattress and the driver and passengers can continue holding high speed.
So with this example alone, which hull is more efficient?

Also, there is a lot more to what makes an efficient boat than just the shape of the bottom. When people say deep-vees are hard to push, what they are really talking about a whole generation of boats that were, and still are overweight to begin with, whether it be production or home built. With these boats being heavy, overweight and using outboards not suited to the design, they are not going to be efficient, no matter what kind of bottom they have.

We do a lot of our engineering & designing based on bottom loading, careful weights and moments analysis and more. And with a sharp entry point, the deep-V hull found on all BMD boats has a high entry angle that delivers a smooth dry ride by displacing water away from the boat ,while a wide bow flair keeps it from rolling back into the boat. Also, our hulls also feature a higher degree of deadrise at the transom for added stability in rougher seas and a smooth ride for all on board.

No they're not.
As BMD-designed hulls carry their chines lower than the waterline, the chines are still immersed during the transition stage from displacement to planing speeds. The large chines on BMD hulls deflect water down and under the hull, acting as two points on which it balances. These points provide a great deal of dynamic stability for a more solid ride while also increasing lift and reducing drag for a faster more efficient running hull. This does not adversely affect performance because, at the boat begins to plane, it rises slightly and the chine is less immersed. That is part of the process in planing boats of reducing surface area, one of the components in drag.

At rest, immersing the chine makes the waterplane wider, increasing the traverse moment of Inertia (or resistance to roll) and the boat more stable. By careful detailing the weights and moments of all our designs, we ensure that the centre of gravity is kept low, ensuring stability not only at rest, but also whilst on the plane. In other words, we design boats, not simply just draw them.

See video's below that demonstrates this.