message: G'day Brian,just ran into an old thread on the
boatdesign.net.
Anti-Rolling Tank https://www.boatdesign.net/threads/anti-rolling-tank.32925/page-3
You had quoted a right up I did on Swan Song's roll tank back then.
Just wanted to update you re the ongoing experiences since I wrote that.
110% better than described in that write up years ago and many 10's of thousand's of offshore miles since.
Never have even thought of using the 'dump valves' in any ocean state.
Just made a run 0f 2800 nm from Honolulu to Los Angeles. Upwind, upwave and up current for the most part.
3 gales, seas always from the beam forward. Days over 10' a few days over 15' two close to 20'.
We also took 2 waves in a 24 hr period broadside from nowhere that broke over the boat. 25'+
Nothing in all that was busted or even any stress crack from the roll tank over the pilothouse right down to the bottom of the hull.
I did a complete inspection once in LA as I was expecting some stress from twisting loads etc...None!
Our 15' tender on top of the boatdeck did try to come free even though I keep it totally deflated on a passage just so it wouldn't have much lift for waves over the deck which is 11 ft over the waterline.
One more time,... all I can say is that Dr Bass took all the data that I'd given him back in 2003 and worked his magic to design ART for Swan Song's specific parameters in all his modeling sea states.
My crew, unpaid as a friend, was a seasoned ocean delivery captain with a YachtMaster UK license. Many ocean deliveries under his command over the years in everything type of boat. Sail/Power/Monohull/Cat/Tri configurations. In gales and clam seas.
He said he'd never ever had a boat take the variety of seas/conditions that we had and do so well. zero faults in his experience. Just one more of the many many who share his opinion.
They have all been aboard if varying sea sates vs sitting at a computer running 'stabilization software'. Gotta be a disconnect there somewhere ;-)
It's funny how I read threads and see how folks, yacht designers in particular, continue to downplay ART's. Somehow the sea states in real life and Dr Gray's specific design for Swan Song and our implementation of it has well proven that there must be some missing data/algorithms in all those 'computer' runs on stabilization methods ;-)
Just thought, that as you had posted that long ago, an update might be interesting to you.
BTW we're leaving LA and heading down to the Canal and back into the Caribbean after 8 years in the Pacific. More than Likely we'll bring Swan Song into Cape Coral/Ft Myers, Fl around Christmas.
I plan on hauling her for a bottom job and need to replace the Wesmar bow thruster. More than likely in Glades boat storage yard in Moore Haven.
Could be a good time to have a look at this boat that seems to perform outside of the world of boat/yacht designers computers ;-)
Cheers
Dave