Abstract: An aircraft includes an engine, a fuel tank, a chamber, a system, and an introduction line. The chamber is located in the tank, occupies only a part of the tank, and includes a sensor for measuring a property of the fuel. The system injects fuel into the line. The introduction line introduces fuel from the injection system into the chamber. The introduction line includes a valve capable of preventing an introduction of fuel from the injection system into the chamber via the line.

Abstract: On board an aircraft, a method is perform in which the following steps are implemented in the following order: measuring a first density value, a first dielectric constant value and a first temperature value of the fuel at a first time, measuring a second density value, a second dielectric constant value and a second temperature value of the fuel, determining parameters of a function for calculating a density from a temperature or a dielectric constant, measuring a volume flow rate value and at least one of a third temperature value and a third dielectric constant value of the fuel in a fuel injection duct in the engine, and determining a density value of the fuel and a mass flow rate of the fuel in the injection line.

Abstract: A liquid sensor system can detect whether liquid is present at a location within a tank or other container, such as an aircraft fuel tank. The system can include a sensor that has a heated negative temperature coefficient (NTC) element and a temperature compensator element. The sensor may be located within the tank. The elements can be polarized by voltages from separate voltage sources. The voltages can be compared to detect a presence or level of liquid within the tank. Only two wires may be needed to connect the sensor with components outside the tank. The system may be able to detect liquid using less than twenty five milliamps and a sensor temperature that is less than two hundred degrees Celsius.

Abstract: A liquid sensor system can detect whether liquid is present at a location within a tank or other container, such as an aircraft fuel tank. The system can include a sensor that has a heated negative temperature coefficient (NTC) element and a temperature compensator element. The sensor may be located within the tank. The elements can be polarized by voltages from separate voltage sources. The voltages can be compared to detect a presence or level of liquid within the tank. Only two wires may be needed to connect the sensor with components outside the tank. The system may be able to detect liquid using less than twenty five milliamps and a sensor temperature that is less than two hundred degrees Celsius.

Abstract: A liquid sensor system can detect whether liquid is present at a location within a tank or other container, such as an aircraft fuel tank. The system can include a sensor that has a heated negative temperature coefficient (NTC) element and a temperature compensator element. The sensor may be located within the tank. The elements can be polarized by voltages from separate voltage sources. The voltages can be compared to detect a presence or level of liquid within the tank. Only two wires may be needed to connect the sensor with components outside the tank. The system may be able to detect liquid using less than twenty five milliamps and a sensor temperature that is less than two hundred degrees Celsius.

Abstract: Described are optical sensing systems. The systems may perform reliably in explosive environments and provide eye protection should breakage of an optical fiber be detected. Sensors of the systems additionally may be self-managing, acquiring and transmitting sensed data as available electrical power permits.

Abstract: A liquid sensor system can detect whether liquid is present at a location within a tank or other container, such as an aircraft fuel tank. The system can include a sensor that has a heated negative temperature coefficient (NTC) element and a temperature compensator element. The sensor may be located within the tank. The elements can be polarized by voltages from separate voltage sources. The voltages can be compared to detect a presence or level of liquid within the tank. Only two wires may be needed to connect the sensor with components outside the tank. The system may be able to detect liquid using less than twenty five milliamps and a sensor temperature that is less than two hundred degrees Celsius.

Abstract: The gauge comprises concentric inner and outer tubes made of insulating material, with two capacitors each constituted by a set of electrodes, each set having at least one pair of two electrodes in strip form extending along the gauge and placed facing each other on the facing walls of the inner and outer tubes.

Abstract: The gauge comprises concentric inner and outer tubes made of insulating material, with two capacitors each constituted by a set of electrodes, each set having at least one pair of two electrodes in strip form extending along the gauge and placed facing each other on the facing walls of the inner and outer tubes.