A method includes simultaneously controlling and sensing aerodynamic loading of a membrane wing using a capacitance of the membrane, the membrane wing stretching under aerodynamic load, leading to thinning of a membrane thickness and increased capacitance, and using knowledge of the membrane's elastic and dielectric material properties to determine an amount of steady aerodynamic lift being generated.

A method includes simultaneously controlling and sensing aerodynamic loading of a membrane wing using a capacitance of the membrane, the membrane wing stretching under aerodynamic load, leading to thinning of a membrane thickness and increased capacitance, and using knowledge of the membrane's elastic and dielectric material properties to determine an amount of steady aerodynamic lift being generated.

A supporting wing structure for an aircraft, in particular for a load-carrying and/or passenger-carrying aircraft, preferably an aircraft in the form of a vertical take-off and landing multicopter having a plurality of electrically driven rotors which are disposed in a distributed manner. The supporting wing structure has a plurality of struts. A first number of the struts are at least largely disposed in a first direction, while a second number of the struts are at least largely disposed in a second direction, the second direction being oriented orthogonal to the first direction. At least the struts of the second number have an aerodynamic profile in cross section, and/or in the struts are connected to one another at least in pairs between neighboring struts by a connecting structure, preferably from individual connecting segments, and the connecting structure or the connecting segments have an aerodynamic profiling. Furthermore an aircraft is provided equipped with such a supporting wing structure.

A supporting wing structure for an aircraft, in particular for a load-carrying and/or passenger-carrying aircraft, preferably an aircraft in the form of a vertical take-off and landing multicopter having a plurality of electrically driven rotors which are disposed in a distributed manner. The supporting wing structure has a plurality of struts. A first number of the struts are at least largely disposed in a first direction, while a second number of the struts are at least largely disposed in a second direction, the second direction being oriented orthogonal to the first direction. At least the struts of the second number have an aerodynamic profile in cross section, and/or in the struts are connected to one another at least in pairs between neighboring struts by a connecting structure, preferably from individual connecting segments, and the connecting structure or the connecting segments have an aerodynamic profiling. Furthermore an aircraft is provided equipped with such a supporting wing structure.

Disclosed are systems and methods for maintaining bulk fuel temperatures in an aircraft. In one aspect, a recirculation system causes fuel to be delivered from a relatively low point near the feed hopper of each tank on the aircraft to one or more outboard locations of the wings. Once there, the fuel, due to gravity, flows back over the lower skin of the wing in channels back towards the fuselage, thus cooling the fuel. In other aspects, control systems are disclosed that coordinate the recirculation based on fuel levels in the tanks and fuel temperatures. The control systems also utilize a fuel scavenge system to maintain acceptable temperatures in the tanks.

Disclosed are systems and methods for maintaining bulk fuel temperatures in an aircraft. In one aspect, a recirculation system causes fuel to be delivered from a relatively low point near the feed hopper of each tank on the aircraft to one or more outboard locations of the wings. Once there, the fuel, due to gravity, flows back over the lower skin of the wing in channels back towards the fuselage, thus cooling the fuel. In other aspects, control systems are disclosed that coordinate the recirculation based on fuel levels in the tanks and fuel temperatures. The control systems also utilize a fuel scavenge system to maintain acceptable temperatures in the tanks.

A blended wing body aircraft having an interior cabin with a usable volume of at most 4500 ft.sup.3 and a cabin aspect ratio of at most 4, wherein a combination of the wings and center body has a wetted aspect ratio of at least 1.7 and at most 2.8. Also, a blended wing body aircraft having an interior cabin with a usable volume of at least 1500 ft.sup.3 and at most 4500 ft.sup.3 and a cabin aspect ratio of at least 2 and at most 4, wherein a combination of the wings and center body has a wetted aspect ratio of at least 1.9 and at most 2.7. Also, a blended wing body aircraft wherein at least each profile section having normalized half-span values from 0 to 0.3 has a leading edge having a normalized height having a nominal value within the range set forth in Table 4.

A blended wing body aircraft having an interior cabin with a usable volume of at most 4500 ft.sup.3 and a cabin aspect ratio of at most 4, wherein a combination of the wings and center body has a wetted aspect ratio of at least 1.7 and at most 2.8. Also, a blended wing body aircraft having an interior cabin with a usable volume of at least 1500 ft.sup.3 and at most 4500 ft.sup.3 and a cabin aspect ratio of at least 2 and at most 4, wherein a combination of the wings and center body has a wetted aspect ratio of at least 1.9 and at most 2.7. Also, a blended wing body aircraft wherein at least each profile section having normalized half-span values from 0 to 0.3 has a leading edge having a normalized height having a nominal value within the range set forth in Table 4.

A low stall or minimum control speed aircraft comprising a fuselage that has vertically flat sides; wings with high a lift airfoil profile of constant chord section set at zero degree planform sweep, twin booms having inner vertically flat surfaces, twin vertical stabilizers, a flying horizontal stabilizer; preferably twin engines having propellers and wherein each engine preferably has a thrust-line that is inclined nose-up to a maximum of +8 degrees, and is parallel to the wing chord underneath wing mounts and landing gear doors that provide surfaces for channeling propeller wash in a rearward direction; all working in concert so that the airplane has an extremely low stall speed and minimum control speed. The engines may be diesel, hydrogen fuel cell, electric fuel cell, diesel-electric, gas turbine or combinations thereof. The propellers may be counter-rotating.