The Dashew Offshore swim step, shown above in its highest evolutionary form on the FPB 97 Iceberg, started out much more modestly.
The original concept was for use when swimming, dinghy boarding, and for man overboard recovery.
Our first test of the swim step came in Antigua, after a 6000NM passage from Capetown, South Africa.
The 72 foot ketch Locura’s swim step was typical for our modest approach.
No matter the boat size, the majority of the hull was reserved for systems, storage, and accommodations. The swim step was sufficient to do its job and nothing more.
Then Fred Somes, the owner of the Deerfoot 63 Astra, decided he wanted more room in which to play. The extra area added waterline and helped appearance.
Fast forward 30+ boats and we were back to simple functional boarding. This worked really well.
But the longer swim platform of the FPB 64s worked better. A key advantage was the ability to bring the dinghy alongside.
So we are slow learners… But eventually Wind Horse got an extension.
Along with easier dinghy operation, the added waterline brings better speed and lower fuel burn. Downside? None, except for added dock length. But then, neither we nor our owners spend much time tied to the dock.
Posted by Steve Dashew (February 25, 2016)
February 25th, 2016 at 5:05 pm
Is that extra solar in the Wind Horse picture?
March 4th, 2016 at 11:49 am
He Gene:
We added four 325 watt panels to Wind Horse in 2012.
February 26th, 2016 at 12:09 pm
Hi Steve,
as you say “added waterline brings better speed and lower fuel burn”. In theory is there a limit to how far you can extend the boat length? On an existing boat, is it always favorable to increase boat length or is there an optimal “sweet spot”?
March 4th, 2016 at 11:53 am
Hi Nils:
There is no easy answer to the lengthening of the waterline and the optimization of this change. With power boats more is almost always better than less. However, if you are headed upwind and there is a sea running, the pitch period and longitudinal stability changes need to be considered, or an unhappy motion is likely to result.
February 28th, 2016 at 12:36 pm
Steve, am I correct in thinking that the swim steps on FPBs are a structurally independent bolted-on extension, not an integrally welded part of the hull? And that, if so, they wouldn’t count when measuring the LOA for legal and registry purposes (i.e. they don’t bump the boat into the next higher class of regulatory and licensing requirements)?
March 4th, 2016 at 11:56 am
Hi Matt:
The question of measurement length depends on the flag state and class. The FPB 64s do have a bolt on extension. The FPB 78s are all welded, but under British rule measure from the rudder post to the cutwater, with other factors applied. The shape of the swim step, and its coamings, also has to be considered.