A protective wall for use in a structure such as a ship comprises a first and second metal layer, with an armor plate in between and layers of elastomeric material between the armor plate and the first and second metal layer respectively. The first and second metal layer having a higher ductility than the armor plate, the armor plate being mounted between the first and second metal layer in a way that allows the first and second metal layers to stretch relative to armor steel plate at least in response to forces resulting from impact by fragments from an explosion. When an explosion occurs in a space bounded by the protective wall, the first and second metal layer deflect under the pressure pulses due to blasts, stretching relative to the armor plate. The armor plate blocks high speed fragments. The elastomeric material has a double function: it increases the resistance of the armor plate to fragments and it allows for separation of the armor plate from the first and second metal layer, allowing them to stretch.

A protective wall for use in a structure such as a ship comprises a first and second metal layer, with an armor plate in between and layers of elastomeric material between the armor plate and the first and second metal layer respectively. The first and second metal layer having a higher ductility than the armor plate, the armor plate being mounted between the first and second metal layer in a way that allows the first and second metal layers to stretch relative to armor steel plate at least in response to forces resulting from impact by fragments from an explosion. When an explosion occurs in a space bounded by the protective wall, the first and second metal layer deflect under the pressure pulses due to blasts, stretching relative to the armor plate. The armor plate blocks high speed fragments. The elastomeric material has a double function: it increases the resistance of the armor plate to fragments and it allows for separation of the armor plate from the first and second metal layer, allowing them to stretch.

An immobilization device for steering systems on marine motors. The device comprises a first and second member, each member having two opposite ends, a non-immobilizing fastener connecting the first member near one of its ends to the second member near one of its ends, and a compressing fastener connecting the first member near the other of its ends to the second member near the other of its ends. The compressing fastener operates to draw the first and second members closer together. The device may also be part of an immobilization system comprising at least one of the devices and a steering system having a steering shaft and a steering ram. The device is assembled around the steering shaft and the compressing fastener is capable of applying sufficient compressive force to resist the steering ram sliding along the steering shaft.

An immobilization device for steering systems on marine motors. The device comprises a first and second member, each member having two opposite ends, a non-immobilizing fastener connecting the first member near one of its ends to the second member near one of its ends, and a compressing fastener connecting the first member near the other of its ends to the second member near the other of its ends. The compressing fastener operates to draw the first and second members closer together. The device may also be part of an immobilization system comprising at least one of the devices and a steering system having a steering shaft and a steering ram. The device is assembled around the steering shaft and the compressing fastener is capable of applying sufficient compressive force to resist the steering ram sliding along the steering shaft.

A marine vessel comprising: at least one buoyant tubular foil; and at least one baffle plate positioned about the perimeter of the at least one buoyant tubular foil so as to protrude into the flow of water passing by the perimeter of the at least one buoyant tubular foil, whereby to create a high-pressure zone fore of the at least one baffle plate and a low-pressure zone immediately aft of the at least one baffle plate, whereby to create a dense stream of supercavitated water immediately aft of the at least one baffle plate.

A marine vessel comprising: at least one buoyant tubular foil; and at least one baffle plate positioned about the perimeter of the at least one buoyant tubular foil so as to protrude into the flow of water passing by the perimeter of the at least one buoyant tubular foil, whereby to create a high-pressure zone fore of the at least one baffle plate and a low-pressure zone immediately aft of the at least one baffle plate, whereby to create a dense stream of supercavitated water immediately aft of the at least one baffle plate.

A water mat is provided. The mat includes a first buoyant layer, a netting layer and a second buoyant layer. The netting layer may be adhered in between the upper and lower foam layers. The netting layer may include crisscrossing fibers having a first set of fibers substantially parallel relative to each other and a second set of fibers substantially parallel relative to each other. The first set of fibers crisscross with the second set of fibers, and are thereby perpendicular relative to the second set of fibers. The netting layer provides additional strength to the mat.

A water mat is provided. The mat includes a first buoyant layer, a netting layer and a second buoyant layer. The netting layer may be adhered in between the upper and lower foam layers. The netting layer may include crisscrossing fibers having a first set of fibers substantially parallel relative to each other and a second set of fibers substantially parallel relative to each other. The first set of fibers crisscross with the second set of fibers, and are thereby perpendicular relative to the second set of fibers. The netting layer provides additional strength to the mat.

A watercraft immobilizing apparatus and system for a marine vessel to passively defend against an attacking engine-powered watercraft includes a towed array of entanglement lines. The entanglement lines can be provided on and administered from removable/replaceable storage cartridges mountable on and/or deployed via davits, outriggers, paravanes, and/or weighted submersible rollers to foul and immobilize propellers and engine cooling water intakes of encroaching watercraft.

A watercraft immobilizing apparatus and system for a marine vessel to passively defend against an attacking engine-powered watercraft includes a towed array of entanglement lines. The entanglement lines can be provided on and administered from removable/replaceable storage cartridges mountable on and/or deployed via davits, outriggers, paravanes, and/or weighted submersible rollers to foul and immobilize propellers and engine cooling water intakes of encroaching watercraft.