On many V hull in Sweden we have flat bottom around 1-1,50 from the back and itīs 10-20 cm widht.(depense on the lenght of the boat). Sorry for my english but it is like a ski/burton. I havent seen this on any RIB from UK? It works very good in high speed. Any brand use it?....
Joakim, it's called "planing pad" and there are a number of RIB designs that have used them - some more effectively than others. You can read a previous discussion about them here http://www.rib.net/forum/showthread.php?t=13222
