What defines a deep v planing hull?

[eze]

Hi folk,

Just a quick enquiry here;

What defines/ constitutes a deep v planing hull as opposed a shallow v planing hull?

I am kind of assuming it is the angle of the 'V'

thank you

eze

[office888]

Originally Posted by eze

Hi folk,

Just a quick enquiry here;

What defines/ constitutes a deep v planing hull as opposed a shallow v planing hull?

I am kind of assuming it is the angle of the 'V'

thank you

eze

Transom deadrise of more than 20 degrees or so.

[eze]

thanks for the quick reply office

[jeffstevens763@g]

Rigid Inflatable Boats - a vast range of quality ribs for both leisure crafts and sports craft from Humber Inflatables

The assault is sold as a deep V but has a planning pad at the stern to help it plane easer at low HP and should go really well with 40-50 hp I had an osprey kestrel with a similar hull with a 40 mariner on years ago and it went very well.

[GuyC]

Another reason for a planing pad is to keep the draught down on a deep v hull.

[Last Tango]

I'd say a "deep V" would be around 25 degrees dead-rise.
20 degrees would be a "medium V"

[two stroke mick]

Could a plaining pad be taken out off the hull of a rib. i.e. put on a pointy end back onto the hull. How hard would this be and would it be worth the effort?

[jeffstevens763@g]

Originally Posted by Last Tango

I'd say a "deep V" would be around 25 degrees dead-rise.
20 degrees would be a "medium V"

near enough, for info below dont think theres a set angle as all boats differ

https://www.tropicalboating.com/2010...-deadrise-hull

[jeffstevens763@g]

Originally Posted by two stroke mick

Could a plaining pad be taken out off the hull of a rib. i.e. put on a pointy end back onto the hull. How hard would this be and would it be worth the effort?

it would give drag as the hull wouldnt pierce the waves

[office888]

Originally Posted by jeffstevens763@g

it would give drag as the hull wouldnt pierce the waves

Depending on the size, the size of the delta / planing pad may decrease wave-piercing performance, and increase pounding if not properly designed (oversized). The boat tends to slam and stop on the flat section, rather than gracefully cut and glide until displacement takes over.

This is why the early generation Avon Adventure 560 rides poorly in rough conditions. If you examine the Searider vs the Adventure, you can see the size of the delta was substantially increased on the rear 1/3 of the hull. It gives amazing planing performance, but at a loss of comfort in rough conditions.

If you look at the hull of the Zodiac Hurricane 733, you'll see it barely has any planing pad to speak of.

Jet drives are another animal entirely, they usually have a rounded section towards the stern in order to boost pump performance.

[GuyC]

Originally Posted by two stroke mick

Could a plaining pad be taken out off the hull of a rib. i.e. put on a pointy end back onto the hull. How hard would this be and would it be worth the effort?

I think if you are driving the boat in a manner where the planing pad comes out of the water on a regular basis then there may be an advantage of having a full V.

Would it be easy?

Taking my Pac 22 as an example, replacing the planing pad with a full V would add a fair bit of volume aft which would potentially upset the trim and add an amount of rake to the keel i.e. deeper at the back than at the front. You could always ballast out the increase in volume but that is just more displacement to move through the water.

Based on my unscientific sample of one, I don't think it would be worth the effort.