interesting boat

[Zen]

Boat Review: Buoyant Etap 28s Delivers Modern Form and Function
At first glance, the Etap 28s is an appealing, nicely finished, modern European-styled pocket-cruiser—but it's what lies beneath the skin that sets it apart. This is one of the few boats with a ship-in-ship, double-hull structure with enough closed-cell polyurethane foam between the skins to provide floatation even if the hull is breached in multiple places. The foam has enough buoyancy to offset the weight of the keel and diesel engine and has been distributed so that a flooded boat would remain stable and be able to make way under sail. This feature can be a significant safety factor to any sailor, but is especially appealing to those sailing in colder waters. In addition to offering positive buoyancy, the Etap 28s sports a spacious cabin and a no-nonsense sail plan that makes it an easy boat to sail. With a compact head, a dedicated nav station, small galley and aft berth, the boat is set up well for family coastal cruising. Details like fiddles and grab rails also showcase its potential as an offshore cruiser.

[Lynx]

As I recall, this has been done before to save weight. The problem came in with water between things. A real mess.

I hope that they have solved it.

[AdriftAtSea]

IIRC, the boat is basically double hulled, since the exterior layer is almost as heavy as a typical fiberglass hull would be.  The biggest problem with the Etaps is the fact that a lot of the stowage space is used up by the inner hull and flotation foam.

[BobW]

I think the biggest problem is the price tag: $137,000!  :o