An aircraft fuel tank system comprising an aircraft fuel tank and a time domain reflectometry (TDR) fuel gauge for measuring a filling level of fuel in the aircraft fuel tank. The TDR fuel gauge comprises an electromagnetic signal generator and a cable, the cable comprising a first cable part and a second cable part which are coupled in series to the signal generator. The first cable part extends downwardly within the fuel tank and the second cable part extends upwardly within the fuel tank. The first and second cable parts are arranged such that for at least one filling level the first cable part extends down into the fuel from an ullage space at a first location and the second cable part extends up out of the fuel into an ullage space at a second location which is spaced apart from the first location.

A modular wing portion for installation into a wing assembly as a pre-assembled unit, the modular wing portion comprising at least one rib and at least one internal fuel tank system component, and a cartridge jig for the assembly of the modular wing portion away from an aircraft wing, the cartridge jig comprising a plurality of secondary support members, each secondary support member configured to receive and support a rib such that a fuel system component can be installed to the rib. Also an aircraft and wings, transport frames and methods of assembly.

A modular wing portion for installation into a wing assembly as a pre-assembled unit, the modular wing portion comprising at least one rib and at least one internal fuel tank system component, and a cartridge jig for the assembly of the modular wing portion away from an aircraft wing, the cartridge jig comprising a plurality of secondary support members, each secondary support member configured to receive and support a rib such that a fuel system component can be installed to the rib. Also an aircraft and wings, transport frames and methods of assembly.

An aircraft fuselage for releasing a fuel tank from inside the aircraft fuselage in case of emergency includes an outer structure, a mounting device to releasably secure a sled device for carrying a fuel tank in an inside of the outer structure, and a first openable release door separating the inside from an outside of the outer structure, wherein the first release door is positioned in relation to the mounting device such that the fuel tank is released through the first release door when the mounting device releases the sled device. A method is disclosed for releasing a fuel tank from inside the aircraft fuselage in case of emergency as well as an aircraft including such an aircraft fuselage.

An aircraft fuselage for releasing a fuel tank from inside the aircraft fuselage in case of emergency includes an outer structure, a mounting device to releasably secure a sled device for carrying a fuel tank in an inside of the outer structure, and a first openable release door separating the inside from an outside of the outer structure, wherein the first release door is positioned in relation to the mounting device such that the fuel tank is released through the first release door when the mounting device releases the sled device. A method is disclosed for releasing a fuel tank from inside the aircraft fuselage in case of emergency as well as an aircraft including such an aircraft fuselage.

An aircraft system that includes an aircraft airframe, a drive unit, a mechanical load, an energy module and an ejection system. The aircraft airframe has an internal compartment. The drive unit is mounted with the aircraft airframe. The mechanical load includes a mechanical load rotor. The drive unit is coupled to and configured to drive rotation of the mechanical load rotor. The energy module is disposed within the internal compartment. The energy module includes an energy source configured to power or fuel operation of the drive unit. The ejection system is configured to eject the energy module out of the internal compartment and away from the aircraft airframe

An aircraft system that includes an aircraft airframe, a drive unit, a mechanical load, an energy module and an ejection system. The aircraft airframe has an internal compartment. The drive unit is mounted with the aircraft airframe. The mechanical load includes a mechanical load rotor. The drive unit is coupled to and configured to drive rotation of the mechanical load rotor. The energy module is disposed within the internal compartment. The energy module includes an energy source configured to power or fuel operation of the drive unit. The ejection system is configured to eject the energy module out of the internal compartment and away from the aircraft airframe