New computer-based tank-testing techniques have added tremendously to the sophistication of hull design in recent years. But one problem remains. No one hull design seems to suit the incredible variety of conditions a seagoing craft is likely to encounter. For example, deep-V hulls, built for stability at speed offshore, unfortunately also mean poor fuel economy, shallow water limitations and, at slow speeds, will rock and roll the breakfast out of even the most seasoned old salt. Modified V's provide more stability, less draft, and better economy, but they lack the seakeeping ability of the deep-V offshore.
In the early 1950's Striker developed a hull design that would maintain the advantages of the other shapes, but eliminate the disadvantages. The result was a unique design which has since become known as the Pentapolymetric hull.
In analysis (see diagram), the forefoot of the Pentapolymetric hull has a sharp, V-shaped entry to cut through seas easily, crisply and with minimal splash.
Amidships, the hull flairs into a "pentalift" shape, creating five planing surfaces: the flat box keel, two inner chines and two outer chines. This unique design not only creates highly efficient lift onto a plane, but excellent lateral stability as well. Finally, the aft section provides tremendous stability through its relatively flat, wide shape, while the concave form sends clean, non-turbulent water to the area of propulsion, creating a very efficient slipstream for the props.
This also allows Striker owners to cut back to one engine on long voyages because this aft hull shape eliminates the steering action that a single rotating prop creates when it "pushes" water against the deep-V typical of other yachts.
Another important benefit to the hull design is its very shallow draft. The low displacement of aluminium, coupled with the elimination of the deep-V amidships, makes it possible to confidently maneuver a Striker in areas far too shallow for other yachts. So in a very real sense, it is the ideal hull design for the oceangoing yacht .. and certainly the only acceptable approach for the finest sportfishing yachts in the world.
Very fine forefoot provides dry entry.
Five planing surfaces amidships insure both stability and efficient planing.
Relative flat, concave aft section means excellent stabilty and efficiency.