March 01, 2009 – Miami, FL – (Boat International Magazine): Most of us who have spent a lot of time on the water are familiar with water taxis. Years ago, in Great South Bay on Long Island, they used beat up old runabouts with noisy 2-stroke outboard. Stealth Yachts, a South African builder of high-performance catamarans has taken the concept several steps further with its new 520RUV. No...it's not a water taxi, it's a modern high-tech water limousine, and a high-performance one at that. Designed as a luxury utility vehicle for waterfront resorts that frequently have to transport their guests to nearby docks and beaches, the 52ft RUV (Resort Utility Vessel) utilizes some pretty advanced technology to produce some rather impressive performance and fuel-efficiency figures. There are several 50ft designs on the market that can cruise at 35+ knots, but they typically burn 3 to 5 gallons per mile at high speeds. The 520RUV is the first one we ever heard of that can cruise at 35 knots on well under 2 gallons of diesel per mile. It also gives an incredibly smooth and comfortable ride even at high speeds in less than ideal conditions. It accomplishes this by employing a hull design called the HYSUCAT (Hydrofoil Supported Catamaran). This design, which was developed by Karl-Günter Hoppe, a German naval architect and professor of fluid dynamics and marine technology, combines the concept of a hydrofoil with a high-speed catamaran hull, by placing a wing between the two hulls amidships, which creates lift, and two smaller wings aft, which provides both lift and stability. When this design reaches speed, the hulls literally rise up so that the boat is riding on only the hydrofoil wings and the lower portion of the two hulls. By reducing the hull's wetted surface, drag is significantly lessened, which translate into some pretty impressive performance and fuel-economy stats. To put the numbers into perspective, the 54ft cruising version of this design, the Stealth 540 Cruiser, can achieve 48 knots with a pair of 800hp 6-cylinder MAN R-6 diesel and cruises at 35.8 knots on 55gph (0.65 nmpg). By comparison, a typical 54 Convertible, with a pair of 1,550hp Cat C32 V12s, achieves a top speed of 38.5 knots and cruises at 30.4 knots on 80gph (0.38 nmpg). To be fair, the Convertible is considerably heavier, but the Stealth 540 is still 41.5 percent more fuel efficient. The 520RUV 54ft cruiser version is currently priced at €925,000 with the 54ft yacht version at €1,250,000. The Q-SPD surface drives also deserve a portion of the credit for these impressive specs. Unlike typical surface drives, these are fixed, with two tine rudders on either side of each prop for steering. These low-maintenance drives, which are made in New Zealand, deliver great performance from a compact and reliable package built out of modern composite materials. By combining all of these advanced features in an attractive design that can carry 30 to 40 passengers, Stealth Yachts has produced an open and sporty marine version of the classic Mercedes 600 limo from the 60s & 70s. It's a veritable "Pope Mobile" that runs (not walk) on water. Now that's truly miraculous! - AT