My V15 pedal boat hulls are developing my ideas on wave piercing hulls.  The benefit of wave piercing is reduced pitching and hence less increase in drag due to waves.

The concept I have been working along is a hull that has large waterplane in the bow but low reserve buoyancy.  It also needs low reserve buoyancy in the stern.  The bow needs to lift once submerged rather than dive.  I am achieving this with flat bottom entry having some rocker and inverted "V" deck.  A few people who have built copies of this design have been impressed with the lack of pitching.

I have taken video of a friends V15 boat in windy conditions.  Notice how little the boat pitches in waves;

He managed to get a good shot of the hull going through a wave:

My dynamic analysis of the V15 hull in waves shows that it has little increase in drag due to wave action until the seat is being regularly immersed.  This occurs with waves over 0.5m  with seat set 300mm above the keel.  It is difficult to asses this in operation because the windage becomes a significant portion of the overall drag.  It is most noticeable when passing through wakes or running with the wind.  There is less propensity to dive.

I have also taken a look at what the 18m proa should do in larger waves.  Attached image shows orientation when sailing at 15kts angled 50 degrees to 3m waves: 

The boat pitches at an angle of 7 degrees with a roll of 15 degrees.  This is the condition where the leading beam will be regularly immersed as it drives up a wave.  In reality I do not think it has the sail power to sail that fast pointing that high because the drag more than doubles due to pitching and forcing lw hull through green water.  A hull with less reserve buoyancy and greater deck clearance would perform better in waves.

There are some ship builders now seriously pursuing hull shapes with lower propensity for pitching.  The linked video gives graphic evidence of the performance advantage:

http://www.youtube.com/watch?v=GJsogw9fHE0

http://www.youtube.com/watch?v=M8w_paqaOog

http://www.ulstein.com/Kunder/ulstein/cms66.nsf/$all/0B7579F9FA87C092C12576CF004D2778?open&qm=wcm_2,18,2,2,4,0

What goes up eventually comes down.  It is preferable not to go up so high to avoid a hard landing.

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