Abstract: A breathing regulator including a first stage regulator, a second stage regulator, a dilution valve, a mixing chamber, and a controller is provided. The first stage regulator is in fluid communication with pressurized source gas. The second stage regulator is in fluid communication with the first stage regulator. The dilution valve is in fluid communication with an ambient gas and includes a size-variable restriction. The mixing chamber is in fluid communication with the second stage regulator, the dilution valve, and a breathing cavity. The controller is in electrical communication with the dilution valve, the second stage regulator, and a plurality of sensors. The controller is configured to: determine a mass flow of the source gas; determine mass flow of the ambient gas; and vary the size-variable restriction of the dilution valve based on the mass flow of the source and/or the mass flow of the ambient gas.

Abstract: A system containing a sensor suitable for pilot respiration inhalation gas data collection and a sensor suitable for pilot respiration exhalation gas data collection can be interfaced to a host computer or operate autonomously. The system or sensor components thereof can be used as a research tool for in-flight monitoring of physiologic effects on pilots' performance caused by the unique conditions faced during flight, in addition to human factors engendered during the course of their duty (fatigue, sleep loss, etc.).

Abstract: A method of producing a custom mask and strap assembly for an aviator's helmet, including: creating a custom mold using additive manufacturing based on at least two physiognomy parameters; forming the custom mask made of an elastomer from the custom mold; assembling the custom mask with a hard shell; and, securing the custom mask and the hard shell to the helmet by a strap assembly, the strap assembly including a strap anchor securable to the helmet and a strap slidably connected to the strap anchor. The strap includes a first side and a second side and further includes a first end securable to a first portion of the mask with the first side facing the mask and a second end securable to a second portion of the mask with the second side facing the mask.

Abstract: An electromechanical valve assembly for controlling oxygen flow from a compressed oxygen source in an aircraft includes: a valve housing, an inlet, an outlet, a passageway allowing flow of oxygen from the inlet to the outlet, a spring-biased conical poppet movable within the passageway; a spring-biased pressure regulating piston engagable with the conical poppet to maintain it in an open position, a push rod engagable with the conical poppet to maintain it in a closed position, and a movable seat in the passageway that engages the conical poppet to regulate gas flow through the passageway. Actuation of an electric motor assembly to cause the seat to move upward results in closing of the valve assembly and shutting off of the oxygen flow. Actuation of the motor assembly to cause the seat to move downward results in opening of the valve assembly and regulation of the oxygen flow.

Abstract: An emergency oxygen system includes: a pressure vessel containing pressurized oxygen; a rupturable seal that confines the oxygen within the vessel until the seal is ruptured; and a valve assembly for controlling the oxygen release and delivery to an aircraft passenger. The valve assembly includes: a valve body with an oxygen outlet connected to the pressure vessel; and a threaded poppet mounted within the valve body whose first end is a pierce point in contact with the seal. The system further includes a pulley that is rotatably connected to the valve body and engages the second end of the poppet; a cable attached to the pulley to effect its rotation; and an oxygen breathing mask connected to the oxygen outlet. Actuation of the cable causes the pulley to rotate and the threaded poppet to move laterally towards the seal, which results in rupture of the seal and allows oxygen to flow through the oxygen outlet to the mask.

Abstract: An electromechanical valve assembly for controlling oxygen flow from a compressed oxygen source in an aircraft includes: a valve housing, an inlet, an outlet, a passageway allowing flow of oxygen from the inlet to the outlet, a spring-biased conical poppet movable within the passageway; a spring-biased pressure regulating piston engagable with the conical poppet to maintain it in an open position, a push rod engagable with the conical poppet to maintain it in a closed position, and a movable seat in the passageway that engages the conical poppet to regulate gas flow through the passageway. Actuation of an electric motor assembly to cause the seat to move upward results in closing of the valve assembly and shutting off of the oxygen flow. Actuation of the motor assembly to cause the seat to move downward results in opening of the valve assembly and regulation of the oxygen flow.

Abstract: A reliable and economical apparatus for relieving pressure in a large aircraft cabin oxygen supply, where multiple oxygen cylinders are used concurrently. A series-parallel array of valves actuated by changes in differential pressure between the oxygen supply and the ambient cabin atmosphere provides overpressure relief The series connection of the valves reduces the risk of open-valve failures, while the parallel connection of sets of series-connected valves reduces the risk of closed-valve failures. The small number of valves used in its design reduces the cost of the apparatus. The series-parallel structure is optionally extended to larger numbers of valves to facilitate the use of less-expensive valves and supporting components without loss of reliability.

Abstract: An improved manually-operable outlet valve for a tank of pressurized gas, especially a tank in a pressurized breathing oxygen system in an aircraft. The valve has a valve body conventionally attachable to a standard oxygen tank. A rotatable valve stem is disposed within a threaded port in the valve body to open and close a poppet valve that mates with a seat machined in the valve body. A torque limiter comprising a stack of Belville washers is disposed between the valve stem and the poppet to prevent over-torque of the valve upon closing of the poppet against the seat. A collar surrounds the stem and rides axially with the valve stem during actuation of the valve. A lever and an electrical microswitch are mounted on the valve body.

Abstract: An improved manually-operable outlet valve for a tank of pressurized gas, especially a tank in a pressurized breathing oxygen system in an aircraft. The valve has a valve body conventionally attachable to a standard oxygen tank. A rotatable valve stem is disposed within a threaded port in the valve body to open and close a poppet valve that mates with a seat machined in the valve body. A torque limiter comprising a stack of Belville washers is disposed between the valve stem and the poppet to prevent over-torque of the valve upon closing of the poppet against the seat. A collar surrounds the stem and rides axially with the valve stem during actuation of the valve. A lever and an electrical microswitch are mounted on the valve body.

Abstract: A reliable and economical apparatus for relieving pressure in a large aircraft cabin oxygen supply, where multiple oxygen cylinders are used concurrently. A series-parallel array of valves actuated by changes in differential pressure between the oxygen supply and the ambient cabin atmosphere provides overpressure relief The series connection of the valves reduces the risk of open-valve failures, while the parallel connection of sets of series-connected valves reduces the risk of closed-valve failures. The small number of valves used in its design reduces the cost of the apparatus. The series-parallel structure is optionally extended to larger numbers of valves to facilitate the use of less-expensive valves and supporting components without loss of reliability.

Abstract: A weather resistant sound attenuating communications headset of modular construction includes two ear cup modules, a microphone boom module, a head band module, a headband cable module, and a termination cable module. The modular construction allows easy replacement of modules as well as selected components of the modules under field conditions without the need for tools. Replaceable water resistant thin film membranes are employed to provide weather protection as well as hygienic protection for the microphone, speaker and amplification electronics. The thin film membranes which cover areas which come into intimate contact with the wearer are easily replaceable under field conditions. Thus a headset that is shared by more than one user can be hygienically cleansed by simple replacement of the microphone and ear cup membranes.

Abstract: A helmet is supplied with a personal alarm safety system (PASS) that detects the absence of motion by the wearer. This usually indicates that the user is unconscious or otherwise incapacitated. Also in the helmet is an automatic activation means which turns on the PASS system as soon as the wearer puts on the helmet. Other features such as visual alarm and inactivation means are included in the preferred embodiment.

Abstract: A microphone circuit control mechanism which is utilized to control the output of a microphone (20) disposed in a breathing mask (12) the microphone circuit extending to a communications device (22) and wherein the microphone circuit control mechanism includes a switch (86) in the microphone circuit, which switch can be toggled between "on" and "off" states in response to a drop in pressure within a pressure sensing chamber (44). The switch (86) is a single-pole double-throw magnetic reed switch which is disposed within the pressure sensing cavity (44), which cavity is in a demand regulator (14). The regulator includes a valve (27) capable of admitting air under pressure into the pressure sensing chamber when required. The magnetic reed switch (86) is toggled in response to movement of a magnet (112) carried by a portion (64) of a valve operating means (30) which portion moves in response to a drop in pressure in the sensing chamber (44).