Abstract: A thermal/overheat sensor for an aircraft includes an outer electrode, an inner electrode, a support layer disposed between the outer electrode and the inner electrode. The support layer contains a state changing material wherein the state changing material is configured to transition between a non-conductive state to a conductive state at a threshold temperature to electrically connect the outer and inner electrodes.

Abstract: An actuator includes a housing with a first end, a second end opposite the first end, and a bore disposed therein. The bore defines a poppet movement axis and extends between the first end and second end of the housing. A solenoid is disposed within the bore and extends about the poppet movement axis. An armature is disposed within the bore and is movable along the poppet movement axis between a disengaged position and an engaged position, the engaged position proximate the solenoid and the disengaged position spaced apart from the solenoid. A magnet is disposed within the bore between the first end of the housing and the armature, the magnet magnetically coupled to the armature to bias the armature towards the disengaged position.

Abstract: A method for preventing chaffing between a linear detector cable and a protective outer sheath including the steps of preparing an elongated polymer tube having a predetermined length and outer diameter, wrapping heat resistant tape having a given width around a distal end portion of the tube to locally enlarge the outer diameter of the tube, and inserting a proximal end portion of the tube into an open end of a metallic protective sheath having a predetermined inner diameter that is slightly greater than or equal to the outer diameter of the tube, so that the heat resistant tape wrapped around the distal end portion of the tube abuts against the end of the sheath to acts as a stop surface.

Abstract: A pneumatic sensing apparatus for use in an overheat or fire alarm system includes a sensor tube containing a pressurized gas in communication with a pressure sensor configured to sense a temperature variation based on changes of the pressurized gas. A pressure switch is coupled to the pressure sensor. The pressure switch includes a signal transducer configured to provide an output indicative of an overheat or fire alarm condition.

Abstract: A sensor includes a housing, at least one sensor component disposed within the housing such that there is space between the housing and the sensor component, and a vibrational damping material disposed within the space to dampen vibration of the sensor components relative to the housing. The sensor can be a thermal sensor. For example, the thermal sensor can be a linear thermal detector, an optical flame detector, or any other suitable type of sensor or combination of sensors.

Abstract: A valve assembly includes a valve with a valve body and chamber. A poppet with a stem and piston is slidably engaged inside the valve body. A poppet release mechanism is included for releasing the poppet from a closed position. A mechanism cover is attached to the valve body. A safety mechanism with a pin, spring, and lever is included for preventing the poppet from moving into a fully open position. A first end of the pin extends into the chamber into a pathway of the poppet and a second end of the pin extends into the valve body of the valve. The spring is positioned between and in contact with the pin and the mechanism cover to bias the pin toward the poppet. A first end of the lever is pivotably attached to the pin and a second end of the lever extends out from the valve body.

Abstract: A linear-thermal-sensor testing system has a signal generator and a reflection analyzer. The signal generator generates a series of damped sinusoidal impulse signals each of a different frequency, and transmits the damped sinusoidal impulse signals to a first end of the linear thermal sensor. The linear thermal sensor generates a reflection signal corresponding to each of series the damped sinusoidal impulse signals at a plurality of electrical discontinuities in the linear thermal sensing array. The reflection analyzer receives a reflection signal from the first end of the linear thermal sensor. The reflection signal has indicia of electrical properties and locations within the linear thermal sensor for each of the plurality of electrical discontinuities. The reflection analyzer calculates the electrical properties and the locations within the linear thermal sensor based on the indicia of the received reflection signal.

Abstract: A detector that detects an alarm and/or fault condition with respect to a pressure of a medium is provided. The detector comprises a housing comprising an access tube configured to receive a medium and a bellows fixed to the housing comprising a cavity and a first contact surface. The detector also comprises an adjustment screw positioned within the cavity of the bellows, coupled to the housing via an insulation member, and comprising a second contact surface. The detector is further configured to detect a change in pressure of the medium based on whether the first contact surface and the first contact surface are in electrical communication.

Abstract: A thermal sensor for an aircraft includes a first electrode, a second electrode, a support layer disposed between the first electrode and the second electrode, and a state changing material is configured to disposed within the support layer, wherein the state changing material transitions between a non-conductive state to a conductive state at a threshold temperature to electrically connect the first and second electrodes.

Abstract: A method of actuating an extinguisher system may comprise retaining a broadhead cutter in close proximity to a burst disc surface, receiving an impulse signal, actuating a spring release mechanism in response to receiving the impulse signal, driving a cutter shaft towards the burst disc surface in response to actuation, and piercing the burst disc surface via the broadhead cutter coupled to the cutter shaft.

Abstract: A multi-condition sensor, comprising a housing defining a component cavity, a pressure input tube disposed through the housing, a fault actuator disposed within the component cavity of the housing and in pressure communication with the pressure input tube through the housing, wherein the fault actuator is configured to extend and contract as a function of pressure from the pressure input tube, an alarm actuator disposed within the component cavity of the housing opposite the fault actuator and configured to be actuated by the fault actuator and to extend to a maximum fault position, and an adjustable alarm contact disposed on an opposite side of the alarm actuator within the component cavity and configured to be adjusted to a predetermined extension length from the housing to provide a predetermined alarm contact position.

Abstract: A eutectic sensing element includes an electrically conductive core extending along a first axis to define a length. The core is coated with a coated with a eutectic material formulated to provide desirable thermal response characteristics. The eutectic sensing element further includes an insulating fiber layer disposed on an external surface of the electrically conductive. The insulating fiber layer includes a strand that extends along the length of the electrically conductive core.

Abstract: A fire suppression system may comprise a shape memory actuation system. The shape memory actuation system may be configured as a retainer that retains a plug and/or a disk. The shape memory actuation system may be a shape memory plug that is configured to discharge from a vessel exhaust port. The shape memory actuation system may be deployable in response to an electrical stimulus (e.g., resistive heating causing the shape memory alloy to have a temperature exceeding a transition temperature).

Abstract: The present disclosure relates to a broadhead cutter activation mechanism and system inside of a fire extinguisher. The broadhead cutter device may be attached to a cutter shaft which is driven downward when the elastic potential energy is released form a spring system. The broadhead cutter device may be configured to pierce and open a burst disc to release the flow of an extinguishing agent under pressure.

Abstract: A method and apparatus for testing a duct leak detection system of an aircraft is disclosed. A sensor of the duct leak detection system is selected at an interface of the duct leak detection system. An alternating current is sent through the selected sensor and a resistance of the selected sensor is measured using the alternating current. An indicative signal is generated at the interface when the measured resistance of the selected sensor is outside of a specification of the selected sensor.

Abstract: According to one aspect, a fire extinguisher includes a fire extinguisher reservoir and a fire extinguisher outlet burst disc that forms a discharge barrier between the fire extinguisher reservoir and a discharge head to retain a pressurized fire extinguishing agent within the fire extinguisher reservoir. The fire extinguisher actuator assembly includes a cutter positioned within the fire extinguisher proximate the fire extinguisher outlet burst disc. The fire extinguisher actuator assembly also includes a motorized activation device having a drive shaft. The motorized activation device is operable to rotate the drive shaft and push the cutter to pierce the fire extinguisher outlet burst disc, thereby releasing the pressurized fire extinguishing agent through the discharge head.

Abstract: A method of suppressing a fire includes the steps of dispensing a first inert gas in a suppression area at an initial rate, detecting an undesired temperature in the suppression area, dispensing a second inert gas at a subsequent rate in the suppression area in response to the undesired temperature and displacing a volume from the suppression area with the inert gas to achieve a temperature below the undesired temperature.

Abstract: A method of manufacturing an overheat or fire alarm detection system, comprises the steps of micromachining a pressure sensor and securing a sensor tube in fluid communication with the pressure sensor. The sensor tube may comprise a hollow tube containing a material that evolves gas upon heating. The micromachining step may comprise doping at least a portion of a first layer, forming a cavity at least partially within the doped portion and forming a deformable diaphragm over the cavity.

Abstract: A thermal event detection and notification system detects a thermal event, a control unit receives information from, the information being indicative of the detected thermal event. The control unit determines, based on the information received, a location of said thermal event.

Abstract: A pneumatic sensing apparatus for use in an overheat or fire alarm system includes a sensor tube containing a pressurized gas in communication with a pressure sensor configured to sense a temperature variation based on changes of the pressurized gas. A pressure switch is coupled to the pressure sensor. The pressure switch includes a signal transducer configured to provide an output indicative of an overheat or fire alarm condition.