Dear Georgs, Thank you for bringing the Power Catamaran List to my attention. To actually discuss all the points raised about power catamarans and their suitability for ocean passages would take many pages of discussion, complete with diagrams and calculations ie: a chapter in the book on power multihulls that I am currently writing.However after reading through all the correspondance there are several things that attract my attention. There seems to be a tendency on the part of some of the correspondents to consider sailing catamarans and power catamarans in the same breath and at the same time to not differentiate between un ballasted monohulls and keel boats [remember this is the sort of thing that got Steve Dashew all concerned]. At one moment power catamarans are being compared with keel boats rather than un ballasted monohulls [bearing in mind that some serious ocean going monohulls now fit internal ballast] and then sailing catamarans are thrown into the mix. Basically I think that all the definitions of what is actually being discussed need to be sorted out and to remember that. As you can't lump all monohulled vessels together, neither can you do the same with multihulls. A planing catamaran is a very different animal to displacement catamaran and both are quite different to a power trimaran. And to make it even more complicated it needs to be considered that even within these basic categories there are numerous sub categories all with rather different characteristics. I guess what I am really saying is that the comparisons need to be made between differing types of boats with a similar purported purpose. Georgs, you seem to be doing this too. "ultimate stability" is what was discussed, which in the real world means the ability to recover from a severe roll. Monohulls to have the edge in this specific area" As Steve Dashew has pointed out. Unless you are considering a fully ballasted keel boat then the monohulls do not have an edge in this area. The unballasted monohull will generally not come back up, unless it is a specialized design such as a lifeboat, and capsizes well before the catamaran. I have not, as yet, heard of a power catamaran being capsized by waves. For all commercial vessels you have to calculate the cross curves of stability and stabilty tests have to be done on the finished vessel. I know that for our ferries all the passengers on one side will only heel the boat 3.5 degrees. The down flooding angle is around 120 degrees if in fact you can somehow get the boat to achieve that angle of heel. I would like to point out that we have now had nine of our catamarans cross the Pacific Ocean on their own bottoms. There are few, if any, design offices that can make that claim. Regards, Malcolm. Malcolm Tennant Multihull Design Ltd PO Box 60513 Titirangi, Auckland 1007 NEW ZEALAND ph +64 9 817 1988 fax +64 9 817 6080 e-mail malcolm@tennantdesign.co.nz www.tennantdesign.co.nz www.catdesigners.com

Thank you, Malcolm, for your comments. I'll review the attachments you sent-which cannot be posted with messages-and see about posting them to the new site. >I would like to point out that we have now had nine of our catamarans cross >the Pacific Ocean on their own bottoms. There are few, if any, design >offices that can make that claim. Could you please recap these trans-Pacific voyages, so that they are posted for the record? How about name of vessel, length, starting and finishing point of the crossings, and dates as available, and current whereabouts of vessel? --Georgs -- Georgs Kolesnikovs Power Catamaran World http://www.powercatamaranworld.com