Abstract: An impact attenuation system comprises an aluminum honeycomb sheet having a top surface and a bottom surface. The aluminum honeycomb sheet defines a plurality of approximately hexagonally shaped cells. The bottom surface defines a single sheet of contiguous cells and the top surface defines two or more islands of contiguous cells separated by one or more slits. At least a portion of one or both of the top surface and bottom surface may be covered by a polymer skin. The polymer skin may comprise carbon fibers and/or fiberglass.

Abstract: An impact attenuation system comprises an aluminum honeycomb sheet having a top surface and a bottom surface. The aluminum honeycomb sheet defines a plurality of approximately hexagonally shaped cells. The bottom surface defines a single sheet of contiguous cells and the top surface defines two or more islands of contiguous cells separated by one or more slits. At least a portion of one or both of the top surface and bottom surface may be covered by a polymer skin. The polymer skin may comprise carbon fibers and/or fiberglass.

Abstract: An impact attenuation system comprises an aluminum honeycomb sheet having a top surface and a bottom surface. The aluminum honeycomb sheet defines a plurality of approximately hexagonally shaped cells. The bottom surface defines a single sheet of contiguous cells and the top surface defines two or more islands of contiguous cells separated by one or more slits. At least a portion of one or both of the top surface and bottom surface may be covered by a polymer skin. The polymer skin may comprise carbon fibers and/or fiberglass.

Abstract: The method for manufacturing rimless spectacles provides a connection region between the lens and the rimless supporting structure wherein the connection region includes a radiation absorbing dye having a predetermined wavelength absorbing band. The lens and rimless supporting structures are then joined together, and the radiation absorbing dye is irradiated by a source of radiation operating at a wavelength within the predetermined wavelength band. Once exposed, the lens and rimless supporting structure are fused together.

Abstract: A local external communication system for use with an enclosed helmet and mask assembly covering the head, ears, nose and mouth of the wearer and provided with earphones and a microphone and a plug for connection with a radio or intercom system, in which a housing adapted to be carried on a wearer's body houses a battery, a speaker and a microphone and carries a receptacle for receiving the communications plug of the mask and helmet assembly. The device includes a unity gain amplifier system having a peak limiting circuit associated with the microphone to limit amplification of external sounds to a safe level. A switch permits the wearer selectively to turn the device off, to listen only, or to both speak and listen through the device.

Abstract: A custom-fitted helmet in which a preformed elastomer sack containing a resin-bead composite adapted to rigidify in response to mechanical deformation accommodates a single rigid outer shell to various individual head sizes. The underside of the sack is formed with circular channels concentric about the top of wearer's head which lockingly receive resilient strips that are part of a preformed inner helmet assembly. The resilient strips are carried on the inner assembly by intermediary energy-absorbing strips which are in turn adhered to a flexible leather liner fitting over the wearer's head.

Abstract: A headset for use in a voice communication system which provides a common audio signal, such as a radio receiver signal, to a plurality of such headsets. The headset includes an earphone having a double voice coil and an ambient sound microphone arranged to receive sounds from the surrounding environment. One of the voice coils is coupled to the common audio signal, while the other coil receives a signal from the ambient sound microphone to permit simultaneous monitoring of the two signals while preventing undesirable signal interaction.

Abstract: A head gear assembly including first and second sound attenuating earcups and means for supporting the earcups over the ears of a wearer and in which each of said earcups has an earphone therein, one of said earcups has a contact microphone therein and switch means is provided for enabling said contact microphone while disabling the earphone in the cup in which the contact microphone is located.

Abstract: A protective helmet assembly includes a flexible inner helmet designed to fit relatively closely over a wearer's head and fitted with one or more impact-absorbing pads, and a hard rigid ballistic outer shell comprising a frontal portion releasably secured over the forehead area of the inner helmet and a rear portion releasably secured over the crown-to-nape area of the inner helmet, and in which assembly the inner helmet is provided with a pad of relatively flexible ballistic material in the forehead region thereof below the frontal portion of the outer shell.

Abstract: A simplified protective helmet of the type in which a molded relatively rigid frame for supporting the helmet headband, chin strap and crown assemblies is formed with an upwardly opening outer peripheral channel for receiving the edge of an outer ballistic shell and with a continuous flange extending generally upwardly and somewhat inwardly from the inner wall of the peripheral channel. The inner surface of the flange is formed with a plurality of spaced strap loop accommodating recesses and is provided with fastener elements at locations between the recesses. Respective adjustable loops at the ends of each of a number of crown straps are received by portions of a frame-carried cord extending across the strap loop accommodating recesses. Headband framing bodies carrying fastener elements are manually releasably secured to the flange carried fastener elements. Spacer elements may be provided between the flange and the headband bodies for smaller head sizes.

Abstract: An alarm system for a cargo box made up of a plurality of panels adapted to be assembled to form the box, in which each panel is provided with a conductor distributed throughout the panel, and in which the conductors of adjacent panels are connected in series when the box is assembled to complete a circuit including an alarm device when a lock is operated. The arrangement is such that the alarm system is silent so long as the conductors complete the circuit. When the circuit is broken with the lock still locked, the alarm system gives a signal indicating that an unauthorized person is attempting either to open the container or to break through a panel thereof in an effort to gain access to the contents.

Abstract: An improved protective helmet for use by an infantryman or the like in which a suspension frame of relatively rigid material has a peripheral channel provided at one location around the frame with a slightly inwardly inclined portion adapted to receive a slightly outwardly directed portion of the edge of a rigid outer ballistic helmet body to permit the body to be swung to a position in which the entire edge thereof is received in the channel and in which position the body is securely held by a single fastener. The frame is formed with a plurality of generally upwardly extending fingers which removably receive envelopes carrying pads of resilient material which adapt the frame to accommodate a range of head sizes. A light line or cord is threaded through holes and slots around the frame releasably to secure both the crown assembly straps and the chin strap supports to the frame while maintaining the positions of the strap ends at predetermined locations around the frame.