What does dead rise mean?

[IaDave]

Buying my first boat this spring and I see in the specs dead rise in a %. What does it mean and how important is it.

[Prowler]

The term deadrise refers to the upward angle of the bottom of a boat, from the keel to the chine, in relation to a level horizontal line, parallel to the the transom of the boat. I hope that is clear enough, but I don't know of any other way to express it. As far a performance goes, the deeper the deadrise, the better the boat will track in heavy water. However, since nothing is free, you can expect the boat to require a bit more power to get the same speed as a flatter bottom would give. Since I use my boat primarily on Lake Michigan, I went for the deepest deadrise I could get to insure good tracking when trolling in rough conditions.

[ffishman]

Its when the Zombies climb out of their graves!!!! Sorry couldn't resist. Above answer is the correct one.

[T Mac]

The term deadrise refers to the upward angle of the bottom of a boat, from the keel to the chine, in relation to a level horizontal line, parallel to the the transom of the boat. I hope that is clear enough, but I don't know of any other way to express it. As far a performance goes, the deeper the deadrise, the better the boat will track in heavy water. However, since nothing is free, you can expect the boat to require a bit more power to get the same speed as a flatter bottom would give. Since I use my boat primarily on Lake Michigan, I went for the deepest deadrise I could get to insure good tracking when trolling in rough conditions.

Correct... but then...it is kind of a mis-used term by a lot of boat salesmen because it actually applies at the transom. (When I was a dealer our competitor used to bring that term up during boat shows to gettem confused ;)...)
See...on today's boats you'll never get the same amount as you go forward on the hull...it changes.
Typically a hull will have more in front, less in back.
So...it is just applicable at the transom hull joint.
Plus... it is an old term. Today's fibreglass hulls and some Aluminums have higher tech hull shapes than just the term deadride can describe.

[frank]

http://www.answers.com/topic/deadrise

[T Mac]

http://www.answers.com/topic/deadrise

Thanks, Frank.

Like I always said when somebody asked me what the deadrise was on a particular boat:

"Where?"

[Miami Vice]

The highest deadrise you can have on a boat is about 24 degrees. This is considered a deep V boat.
This boat with blast through the waves and cut the water like a knife. But in the process it will burn a ton of gas. Also when drifting it can rock & roll more than other boats in a beam sea.
A modified Deep V might be in the 17 to 21 degrees range. This type of boat will give up some ride quality in heavy seas but it will burn less gas and rock & roll less when you are drifting.
An almost flat bottom boat might be about 10 degrees. This type of boat will plane very easily, and stay on plane at low speeds. It will be very frugal on gas, and it will hardly rock & roll in a beam sea compared to the deep V hull.
When you discuss deadrise you always talk about the stern of the boat.
Sure when you look at the front of a boat or the middle of the boat there will be a steeper angle (more deadrise) than in the stern, but when you compare the sea keeping abilities of different boats you usually only look at the measurement at the stern.
Miami Vice