A three-dimensional auxetic structure, comprising a plurality of adjoining hollow cells, each hollow cell having cell walls and a transversal cross section of the plurality hollow cells following a two-dimensional auxetic pattern, each cell wall comprising folding lines parallel to a plane containing the auxetic pattern such that peaks and valleys are defined in the cell walls and the cell walls being foldable along the folding lines.

An example system for suppressing a fire condition in an aircraft includes a supply of fire suppressant agent on-board the aircraft, a conduit coupled to the supply of fire suppressant agent and configured to carry fire suppression agent, an inlet located downstream of the conduit that is coupled to the conduit and is configured to be attached to a cargo container in the aircraft to deliver the fire suppression agent directly into the cargo container, a valve connected to the conduit between the supply of fire suppressant agent and the inlet, a detector located inside the cargo container, and a computer controller in communication with the valve and in communication with the detector, and controlling operation of the valve for delivery of the fire suppression agent into the cargo container based on an output received from the detector.

A propulsive assembly for aircraft comprising an engine, a nacelle arranged around the engine and a pylon supporting the engine, the nacelle including two engine cowls and reversing cowls, each cowl having an internal skin, characterized in that at least one of the cowls of the nacelle comprises at least one box arranged in a space situated between the internal skin of the cowl and the engine, the box delimiting a volume of inert material, the inert material being flame retardant foam. This box partially blocks a zone of the engine where a fire is likely to begin, which makes it possible to limit the volume of a fire zone of the engine, and thus reduce the quantity of extinguishing agent which is necessary to extinguish a fire in the zone of the engine concerned.

A gas turbine engine includes an engine core having a compressor, a combustor fluidly connected to the compressor, and a turbine fluidly connected to the combustor. A core nacelle is disposed radially outward of the engine core. A cavity is disposed between an inner surface of the core nacelle and an outer surface of the engine core. The cavity includes a vent disposed at an aft end. The vent includes at least one flap configured to be maintained in an unrestricted position and in a restricted position. An actuator is configured to control the position of the at least one flap.

An aircraft with at least one propulsion assembly and its fire-fighting system, which includes two reservoirs of extinguishing agent, and, associated with each reservoir, a control that can be actuated by a pilot to open the reservoir, a detection assembly to detect a fire and emit, if appropriate, a fire alert signal, the propulsion assembly including a first and a second compartment each including at least one fire zone, the fire-fighting system including a bypass valve controlled by a localization unit, a set of pipes connecting each reservoir to each of the fire zones through the bypass valve, the localization unit configured to detect a fire in a fire zone in the first compartment, and, if appropriate, control the bypass valve so it adopts a first state where the extinguishing agent in a reservoir is expelled towards the one or more fire zones in the first compartment after activation of the control associated with a reservoir, the bypass valve otherwise being controlled to adopt a second state, in which the extinguishing agent in a reservoir is expelled towards the one or more fire zones in the second compartment.

According to an aspect, a fire suppressant system includes a first fire bottle in operable communication with a first cockpit control switch via a first channel, and a first sensor-based switch via a second channel. Additionally, the fire suppressant system includes a second fire bottle in operable communication with a second cockpit control switch via a third channel, and a second sensor-based switch via a fourth channel.

A power relay is controlled by the presence of Volatile Organic Compounds that are often emitted by outgassing from electronic components during overheat and failure conditions. The relay housing contains a standard power relay of single pole single throw (SPST) or a multi-pole double throw relay depending on the application. A micro VOC integrated circuit is placed within the housing allowing access to ambient air through ports in the side of the relay. Air quality is sampled periodically or continuously as is required by the system to adequately monitor for fault events and, in the event of a fault, latch the relay mechanism OPEN breaking the flow of electrical energy the circuit downstream.

Systems and methods relating to foreign object detection with respect to passenger-accessible stowage compartments are provided. According to one example, sensor data is captured via a sensor subsystem that includes a sensor associated with each of a plurality of stowage compartments. For each of the stowage compartments, a baseline condition is identified in which foreign objects are absent from the stowage compartment. A foreign object is detected within a stowage compartment based on the sensor data received for the stowage compartment and the baseline condition identified for the stowage compartment. An audit of the stowage compartments is conducted, and based on the audit, an indication that the foreign object is detected within the stowage compartment is output. This indication may identify the stowage compartment containing the foreign object among the plurality of stowage compartments.

A propulsion assembly including a turbomachine attached to a pylon, and a fire-fighting system, the turbomachine including fire zones, the fire-fighting system including two reservoirs of pressurized extinguishing agent in the pylon and a distribution line connecting the reservoirs to nozzles. The distribution line includes connected pipes having a low point between the reservoirs and the nozzles, and, for each low point, a fluid drainage device for evacuating fluid. The drainage device includes a fluid passage for fluid evacuation from the distribution line and a mechanism for shutting off the fluid passage, the mechanism movable under effect of distribution line pressure, between a first position where it opens the fluid passage and a second position where it closes the fluid passage, the second position being reached when the pressure in the distribution line is greater than or equal to a predetermined pressure.

A waste compartment system for an aircraft can include a motor operated door and a proximity sensor configured to sense an object near the door or approaching the door. The system can include a control module operatively connected to the proximity sensor and configured to open the door in response to the proximity sensor sensing an object near the door. The control module can be configured to close the door after a preset time after the proximity sensor senses an object.