Abstract: A method of encapsulating temperature-sensitive electronic devices such as solid state memory devices used in aircraft for recording flight data and the like in a wax-like material having a high heat of fusion to establish a heat sink for protecting the device against intense heat resulting from fire includes the preparation of a wax "preform" under heat and pressure in a closed chamber for minimizing oxidation thereof and thereafter transferring the preform by the application of heat and pressure to move the material in a softened condition into a mold cavity supporting the memory devices and forming the material to encapsulate a printed circuit board, carrying memory devices to exclude air and protect the same from deleterious effects of intense heat.

Abstract: A crash survivable protective enclosure for flight data recorders, cockpit voice recorders and memory devices employing a solid state memory element includes a conformal coating of air excluding plastic material around the memory element. An inner shell of metal having a low position on the periodic table in comparison to tin and copper associated with the memory element is provided to enclose the memory element and the conformal coating. Heat insulating fillers are provided around the inner metal shell which serves as a sacrificial anode when the enclosure is exposed to salt water. An outer metal shell formed of high strength material is provided around the insulating filler for resisting physical forces applied from an exterior of the protective enclosure during a crash.

Abstract: A crash survivable enclosure for flight data recorders used in aircraft and other vehicles operating over land and water includes a strong, light-weight metal shell for enclosing and protecting an information storage device having power, signal, and address lines connected thereto. The memory device is supported inside the shell in a wax filler of the type having a high melting temperature and a high heat of fusion to act as a heat sink for absorbing a large quantity of heat to minimize possible damage to the memory device because of excessive heat, flames and/or high temperature. A strong lightweight metal shell is provided to enclose and protect the inner shell and contents against substantial, external mechanical forces commonly occurring in a crash and flames, heat and fire resulting therefrom.

Abstract: Solid state memory devices employed in crash survivable flight data recorders must be thermally insulated to prevent loss of stored data if the aircraft burns. To provide adequate thermal isolation at minimal size, the solid state electronic memory devices (26) are encapsulated in a synthetic organic wax or pentaerythritol (28) that exhibits a phase transition at a temperature: (a) above the normal operating temperature of the memory unit (10); and below the maximum acceptable peak temperature for the memory devices (26). The synthetic organic wax of pentaerythritol (28) is surrounded by a thermal liner (18) constructed of solid thermal insulating material. A metal enclosure (12) houses and protects the thermal liner (18), the synthetic organic was or pentaerythritol (28) and the memory devices (26).

Abstract: In order to provide a magnetic tape recorder where the magnetic tape and tape reels are driven by a drive belt with the capability of operating in temperature extremes, the drive belt is composed of silicone rubber that has been cured with a peroxide curing agent.