An unmanned aerial vehicle (“UAV”) having an envelope and a drone body capable of delivering packages is disclosed. Methods for utilizing UAVs to deliver packages and systems for housing UAVs are also disclosed. In one aspect, a UAV includes a dual cavity envelope having an ellipsoid shape with a first internal cavity and a second internal cavity, the first internal cavity configured to hold a lighter than air gas, the second internal cavity configured to hold a heated gas, and a drone body attached to and located below the dual cavity vertical envelope.

An unmanned aerial vehicle (“UAV”) having an envelope and a drone body capable of delivering packages is disclosed. Methods for utilizing UAVs to deliver packages and systems for housing UAVs are also disclosed. In one aspect, a UAV includes a dual cavity envelope having an ellipsoid shape with a first internal cavity and a second internal cavity, the first internal cavity configured to hold a lighter than air gas, the second internal cavity configured to hold a heated gas, and a drone body attached to and located below the dual cavity vertical envelope.

A fluid tank for integration into a structure of an unmanned aircraft includes a shell having a first axial wall, an oppositely arranged second axial wall, an upper side, a lower side, and an enclosed interior, at least one receiving chamber in the interior for storing fluid, and a collection chamber, which is arranged on the lower side and which is fluidically connected to the at least one receiving chamber. The collection chamber includes a bottom surface, through which there extends a drain, wherein a covering surface is arranged above the bottom surface and covers at least a portion of the collection chamber. At least one flow opening could be arranged on an upper side of the collection chamber, which flow opening allows gas bubbles to escape in the direction of the upper side of the fluid tank.

An aircraft includes a fuselage airframe and a wing airframe that is subject to flight loads. The fuselage airframe includes fore/aft floor beams having a plurality of floor intercostals laterally extending therebetween and fore/aft roof beams with a plurality of roof intercostals laterally extending therebetween. Each of a plurality of cabin frames extends generally vertically between respective floor and roof beams. The wing airframe includes forward and aft wing spars with a plurality of wing ribs extending therebetween. At least one fuel tank, that is configured to contain a pressurized fuel such as pressurized hydrogen fuel, integrally forms at least a portion of one of the beams, the intercostals, the frames, the spars and/or the ribs such that the fuel tank is subject to the flight loads.

An aircraft includes a fuselage airframe and a wing airframe that is subject to flight loads. The fuselage airframe includes fore/aft floor beams having a plurality of floor intercostals laterally extending therebetween and fore/aft roof beams with a plurality of roof intercostals laterally extending therebetween. Each of a plurality of cabin frames extends generally vertically between respective floor and roof beams. The wing airframe includes forward and aft wing spars with a plurality of wing ribs extending therebetween. At least one fuel tank, that is configured to contain a pressurized fuel such as pressurized hydrogen fuel, integrally forms at least a portion of one of the beams, the intercostals, the frames, the spars and/or the ribs such that the fuel tank is subject to the flight loads.

The present disclosure provides systems and methods for processing ammonia. The system may comprise one or more reactor modules configured to generate hydrogen from a source material comprising ammonia. The hydrogen generated by the one or more reactor modules may be used to provide additional heating of the reactor modules (e.g., via combustion of the hydrogen), or may be provided to one or more fuel cells for the generation of electrical energy.

Disclosed herein is a VTOL tilt-wing aircraft that serves as a 4-6 passenger airliner for scheduled service between city centers and that is optimized for travel distances from 100-500 miles fully loaded with passengers and fuel. The VTOL aircraft solves technical, cost, and time problems inherent in other forms of transportation, including, but not limited to, rail, passenger airlines, and helicopters. The VTOL aircraft (1) takes off and lands like a helicopter, (2) flies fast like a jet, and (3) costs less than or comparable to a helicopter.

Aircraft hydrogen fuel systems and methods and systems of starting such systems are described. The aircraft hydrogen fuel systems include a hydrogen burning main engine, a main tank configured to contain liquid hydrogen to be supplied to the main engine during a normal operation, and a starter tank configured to contain gaseous hydrogen to be used during a startup operation of the main engine. Methods and processes for starting and/or restarting such systems are described.

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.