Originally Posted by olianta
What is your opinion of these rectangular portholes in the hull (I refer to the Sly 43 video). They look trendy from outside but do they not compromise hull stiffness and thickness? Are they not susceptible to outside damage from docks or other boat hulls despite fenders. I have not been inside such a boat but IMHO there is not much gain in light from such portholes near the water or may be someone will enjoy looking the water from the leeward side.
Yes the gain in virtual space and scenery, not to mention light is huge. They call them inserts and they are not just a piece of plastic but normally a block with air inside. They have more to do with airplane "widows" than anything else. They started to be used in fast motorboats (much bigger than in sailboats) and the stress a hull of a fast motorboat can take is bigger than the one of a sailboat.
Today even some cruiser racers, more used to race than cruise use them. I don't know how they work regarding hull strength but obviously they can be used if the the hull is already designed to include them without great structural disadvantage otherwise very fast performance boats like the Sly 43, or performance cruisers used for racing would not be using them.
I am absolutely sure that the NA that design those boats know what they are doing, since almost all boats are using them and many of them are designed by some of the best NA in the world.