STEALTH 520 patrol by SeaShuttle

STEALTH 520 patrol

Hysucat ® The HYdrofoil SUpported CATamaran (HYSUCAT) is an integrated design comprising a catamaran hull equipped with a hydrofoil system between the demi-hulls which carries a part of the craft’s weight at speed.

This development reflects 30 years of Professor Karl-Gunter Hoppe’s research before and while employed by the University of Stellenbosch, as Senior Lecturer in Fluid Mechanics and Marine Engineering.

The efficient load carrying capability of the hydrofoil system combined with the inherent stability and pleasant seakeeping properties of the

planing catamaran result in a most economical high speed surface craft with excellent seakeeping behaviors. The specific hull design is an asymmetrical catamaran hull with a centre-pod rounded tunnel, with the foils fitted forward and aft.

powerful, functional . . . 2

Performance Technology surface propulsion STEALTH integrated surface propulsion 6-blade surface piercing propeller Low maintenance Smooth and quiet

engineering excellence Man R6-800 common rail engines BOSCH in-line injection pump Electrical engine speed governor Globally recognized for efficiency, and an early flattening torque curve while being the quietest

reliability factors Superb marine engineering Service access to systems Fuel and oil management systems

hydrofoil system Central main and aft stabilizing HYSUCAT foil system

instinctive innovation

Performance Technology cont. integrated surface drive (ISD) The STEALTH technology Integrated Surface Drive (ISD) unit is built as part of the vessel’s hull. This optimally positions the surface piercing propeller in the water flow from the transom with minimal external moving components – no hydraulic cylinders, steering rods or thrust bearing with their vulnerable soft covers exposed to grounding and collision damage and vulnerable to corrosion and marine growth. The ISD is considerably simpler and more robust than most conventional drive systems, competitor surface drives, stern drives, water jets and pod drive units.

advantages of ISD It makes use of high-efficiency surface propellers which are typically have higher efficiency than other propeller types. Further, the drive-shafts exit the transom of the vessel at and extremely shallow angle which gives a higher useful forward thrust component than normal propeller-shaft systems. Shallow draft characteristics due to propeller-shaft exit through the vessel’s transom and integrated rudder mounted athwarthships of the surface propeller. 4

Extremely low maintenance costs as the surface propeller and rudder are the only eternally fitted components of the drive system – all other components are internally fitted within the hull. They are not subjected to impact and corrosion damage and can be easily accessed with the vessel in the water for maintenance. As the hull transom is positioned forward of the vessel stern and recessed into the aft hull area, the ISD does not protrude past the stern of the vessel. This protects the ISD from stern damage and safely positions the propeller away from any user activities at the stern of the vessel. Excellent astern performance from the surface propeller due to the angled-shape of the drive housing deflection propeller wash under the vessel’s hull when reversing. An integrated exhaust exit for propeller ventilation at slow speeds which aerates the surface propeller and promotes rapid acceleration to planning speeds. The concealed and integrated nature of the exhaust outlet promotes rapid attenua-

No propeller height adjustment is necessary due to the opti-

tion of exhaust noise which enables vessel pass-by noise lev-

mal design integration of the ISD for each particular hull size.

els to be below international limits for vessel noise emissions.

Performance Autonomy vessel speed Versatile speed range with a loiter speed of 7-10 knots, operational speed of 30-38 knots and a maximum speed of 45 knots. In general, the HYSUCAT hull will allow the STEALTH 520 patrol to maintain a speed of 30% faster than any equivalent sized monohull vessel in any given sea-state.

vessel range High efficiency HYSUCAT hulls mean better fuel consumption for a specified vessel speed. The effect of this is a high vessel range. The STEALTH 520 patrol is fitted with 3,000 liter fuel tanks which gives the vessel and operation range of 500 nautical miles at 37 knots.

Features ride quality and seaworthiness The ride-comfort of a catamaran hull is significantly improved by the high slenderness ratio of the individual catamaran hulls. The narrow hulls allow the vessel to punch through waves resulting in lower vertical accelerations which are perceived as a softer and more comfortable ride for the crew. The ride quality is further improved in rough seas due to the motion damping effect of the hydrofoils. The overall result is a vessel with low impact loads which is ideal for reducing crew fatigue and stable when used as a weapons platform.

damage stability Each hull of the vessel is divided into six independent watertight compartments with three in each hull. If one compartment is damage and flooded, the vessel will be capable of returning to harbour under its own power. The vessel will not sink if any three compartments are damaged or flooded providing a safe platform for the crew until rescue.

ballistic protection The lightweight, composite construction of the hull, deck and superstructure of the STEALTH 520 patrol incorporates manufacturing techniques using core materials and Kevlar fabrics. Windows are bullet-resistant glass. These construction methods provide vessel and crew protection against most small-armour fire such as the widely used AK47. 9

Purpose The STEALTH 520 patrol is purposely designed and developed to provide a craft that has a long range, speed and comfort and can be deployed for intercepter and boarding purposes. Safety of the crew is assured by deploying ballistic proof construction methods and materials while the interior space and visibility can enable crew to engage in offensive activities with the correct ensemble of weapon systems. Various layout options are available including cabins, galley and heads. Deck areas are strengthened to accommodate a variety of light weight weapon systems while ample cargo area is available for ammunition storage.

Specifications and Layout Overall Length:

52 ft

15.5 m

Beam:

18 ft

5.5 m

Cruising Speed:

35 knots

Maximum Speed:

45 knots

Draft (maximum load):

3”9”

1.2m

Fuel Capacity:

790 US gal

3 000 l

Water Capacity:

114 US gal

430 l

Weight (dry):

39 700 lbs

18 000 kg

Range:

500 nm at cruising speed

layout, accommodation and storage The foredeck has a secure, reinforced weapons platform accessible from the interior of the vessel via a watertight door. The aft cockpit has a reinforced deck suitable for fitting a weapons pedestal. The internal ammunition-locker is centrally located within the ballistically protected hull with separate small-quantity ammunition lockers located at each weapons pedestal. Accommodation is provided for five crew. There are workstations for helmsman with two supporting navigation and tactical stations and with additional seating for two crew. All seating uses shockmitigating, jockey style seats. Over-night berths are provided for four crew in one cabin with a private berth in a separate captain’s cabin. There are galley and toilet and shower facilities. All accommodation spaces are air-conditioned.

www.stealthyachts.com www.stealth-technology.com This document is not contractual. All descriptions and illustrations are only indicative. We reserve to modify or improve our product without notice. September 2013