An aircraft has a first container 110, preferably a rigid fuel tank, containing a first type of fuel 111, and variable volume container 120 within the tank containing a second type of fuel 121, at least one of the fuels is provided to an engine. Preferably, the first fuel is regular aviation fuel, the second sustainable aviation fuel (SAF). Also claimed is a fuel storage structure 101 including the tank and container, with a fuel release 135, such as a valve, for providing both fuels to the engine, SAF may be released into the tank, or provided to the engine independently from the regular fuel (fig.4). A controller (fig.6,180) may operate a valve actuator based on flight information such as altitude, speed or route information, and/or based on engine feed flow rate, and/or to provide a certain ratio of the fuels. Alternatively, the valve may be passive float operated depending on a volume of one of the fuels in the tank. The variable volume container may be an elastic bladder, or have a bellows structure (fig.3), and made from reinforced flurosilicone; the container either mounted to an internal surface of the tank (fig.2a) or floating unattached.
Aircraft fuel storage structure
2024-11-27
Patent
Electronic Resource
English