The invention is a system that enables passive sonar identification of underwater items by making use of lift bags and/or flags, having distinctive sequences of bands of sonar-signal-reflecting materials, wherein the lift items are partially inflated so as to present a predictable orientation with respect to the floor of a body of water and its surface.

A technique for managing an attachment between first and second portions of a device. The technique includes a retaining component having a first state in which the retaining component maintains the attachment between the first and second portions by virtue of a rigid characteristic and a second state in which the retaining component loses the rigid characteristic and no longer maintains the attachment. The retaining component transitions from the first state to the second state upon exposure to liquid water.

A technique provides a modular sensing device having multiple separable modules attached end to end. The modules are selectable based on mission requirements, with different modules and combinations thereof selected for different mission types and/or requirements.

Devices and methods for aiding a large area search for objects. A searcher transmits interrogation signals of long range relative to the return range to be received by a device at the target object. The target device responds with a ping signal modified to be more easily found by means of information contained in the interrogation signal. The information may be in the nature of the received signal or data encoded and embedded. The target device may use a microprocessor to do complex operations using the information from the interrogation signal and other information. Detection of a weak ping is facilitated by such means as being beamed in the direction of the interrogation, arriving at a predictable time, or having parameters adapted to values requested by the searcher. The object is then intercepted with help of the ping or other signals from the device.

Devices and methods for aiding a large area search for objects. A searcher transmits interrogation signals of long range relative to the return range to be received by a device at the target object. The target device responds with a ping signal modified to be more easily found by means of information contained in the interrogation signal. The information may be in the nature of the received signal or data encoded and embedded. The target device may use a microprocessor to do complex operations using the information from the interrogation signal and other information. Detection of a weak ping is facilitated by such means as being beamed in the direction of the interrogation, arriving at a predictable time, or having parameters adapted to values requested by the searcher. The object is then intercepted with help of the ping or other signals from the device.

An apparatus for use with a submerged compartment is presented. The apparatus includes deployable physical connection hardware provided with the submerged compartment. The deployable physical connection allows for a transfer of fluid between the submerged compartment and a region near a marine free surface when deployed. The deployable physical connection hardware comprises a hose in one aspect.

An apparatus for use with a submerged compartment is presented. The apparatus includes deployable physical connection hardware provided with the submerged compartment. The deployable physical connection allows for a transfer of fluid between the submerged compartment and a region near a marine free surface when deployed. The deployable physical connection hardware comprises a hose in one aspect.

A buoy system according to one embodiment of the present invention includes a buoy body configured to provide buoyance; a fixing belt configured to fasten the buoy body to a ship structure; an auto-release unit configured to release the buoy body to be buoyed by releasing the fixing belt when a predetermined water pressure is reached; and an auto-reel chain box fixed to the ship structure, being opened in conjunction with releasing of the fixing belt, and including a chain which is reeled out when the buoy body is buoyed, wherein the auto-reel chain box comprises: a weight provided in the auto-reel chain box and being movable upward and downward according to a water pressure and buoyance; a pulley provided in the auto-reel chain box, having the chain wounded thereon and a plurality of teeth on an outer circumferential surface thereof; and a shaft having one end connected to the weight and the other end engaging with the teeth to fix the pulley and provided to be rotatable around a portion fixed in the auto-reel chain box.

Embodiments of emergency locating devices are described. In one embodiment, an emergency device includes a fixed part and a breakaway part, with the fixed part sized and shaped to receive the breakaway part, and wherein the breakaway part is buoyant in water and includes a signaling device that can transmit a distress signal.

Embodiments of emergency locating devices are described. In one embodiment, an emergency device includes a fixed part and a breakaway part, with the fixed part sized and shaped to receive the breakaway part, and wherein the breakaway part is buoyant in water and includes a signaling device that can transmit a distress signal.