An F18HT rig on an A-cat platform ?

Talking about a touchy boat. The A-cat hulls don't nearly have enough volume to handle that rig well in any decent wind and seastate with 2 people on board. Sorry. Note I'm not saying anything aout stuff breaking here, just commenting on how it will behave. That F18HT rig is very large rig and also the A-cat platform is narrow at only 2.3 mtr wide. Wasn't the F18HT mast also over 15 kg's ? Replacing the 9-10 kg A-cat mast with that one will make a difference in the dive tendencies as well. Not to mention the fact that it is 10 mtr tall, which is about a whole meter (3 feet) more then most A-cats masts.

That is not going to work out well, sorry. The specs are simply wrong.

Cutting down the F18HT mast is silly as you'll end up with an extremely stiff mast that way, which is really not what you want on a sensitive platform like the A-cat. The boat will be transforming into a bicepts training apparatus (mainsheet sawing) rather then a well behaved racing boat.

I'm sorry but may I say that this discussion is going into the direction of putting a Ford Cossworth motor onto a go-cart in addition to adding a passengers seat and then expecting to good (racing) results.

Wouter