An unmanned aerial vehicle (UAV) includes a vehicle body and a flight control circuit. The vehicle body includes a housing and a fan. The housing includes two vents arranged at two ends of the housing and in communication with an internal space of the housing. The two vents and the internal space form a heat dissipation air passage. The fan is arranged at one of the two vents, and is configure to drive external air into the heat dissipation air passage and expel internal air from the heat dissipation air passage. The flight control circuit is arranged inside the housing and is configured to control flight parameters of the UAV. The heat dissipation air passage is configured to dissipate heat generated by the flight control circuit.

An unmanned aerial vehicle (UAV) includes a vehicle body and a flight control circuit. The vehicle body includes a housing and a fan. The housing includes two vents arranged at two ends of the housing and in communication with an internal space of the housing. The two vents and the internal space form a heat dissipation air passage. The fan is arranged at one of the two vents, and is configure to drive external air into the heat dissipation air passage and expel internal air from the heat dissipation air passage. The flight control circuit is arranged inside the housing and is configured to control flight parameters of the UAV. The heat dissipation air passage is configured to dissipate heat generated by the flight control circuit.

High-temperature gas exhausted to outside of an aircraft including exhaust air from an air conditioner is prevented from thermally influencing an airframe. An aircraft includes, in an airframe, an exhaust port configured to exhaust, to outside of the aircraft, high-temperature gas that flows through an exhaust duct provided in an air conditioner and has temperature higher than allowable temperature of GFRP used as a material of a fairing, and a partition as a turning reduction portion configured to reduce a turning component contained in flow of the high-temperature gas before the high-temperature gas is exhausted to the outside of the aircraft.

An airborne vehicle made of thermally non-conductive materials and method for thermal conduction in an airborne vehicle are disclosed. The airborne vehicle comprising at least one structural element made of material with high thermal conductivity coefficient embedded in the airborne vehicle body. In some embodiments wherein the thermally conductive structural element is a longitudinal profile with hollow center along it. The method comprising disposing structural element with high thermal conductivity embedded in the airborne vehicle and providing thermal pass with high thermal conductivity from the heat source to the structural element with high thermal conductivity, to allow heat to dissipate through the structural element with high thermal conductivity.

An airborne vehicle made of thermally non-conductive materials and method for thermal conduction in an airborne vehicle are disclosed. The airborne vehicle comprising at least one structural element made of material with high thermal conductivity coefficient embedded in the airborne vehicle body. In some embodiments wherein the thermally conductive structural element is a longitudinal profile with hollow center along it. The method comprising disposing structural element with high thermal conductivity embedded in the airborne vehicle and providing thermal pass with high thermal conductivity from the heat source to the structural element with high thermal conductivity, to allow heat to dissipate through the structural element with high thermal conductivity.

A hinge assembly of a system for operating a door of an aircraft includes a bracket secured to a structure of the aircraft. The bracket includes a first forward joint and a first aft joint separated by a first distance along a first line. A forward link is coupled to the first forward joint. An aft link is longer than the forward link, and is coupled to the first aft joint. A door coupler is secured to a door. The door coupler includes a second forward joint and a second aft joint separated by a second distance that is less than the first distance. The second distance is along a second line that is parallel to the first line in a stowed position. The forward link is further coupled to the second forward joint, and the aft link is further coupled to the second aft joint.

A hinge assembly of a system for operating a door of an aircraft includes a bracket secured to a structure of the aircraft. The bracket includes a first forward joint and a first aft joint separated by a first distance along a first line. A forward link is coupled to the first forward joint. An aft link is longer than the forward link, and is coupled to the first aft joint. A door coupler is secured to a door. The door coupler includes a second forward joint and a second aft joint separated by a second distance that is less than the first distance. The second distance is along a second line that is parallel to the first line in a stowed position. The forward link is further coupled to the second forward joint, and the aft link is further coupled to the second aft joint.

An aircraft propulsion system with a drag reduction portion adapted to reduce skin friction on at least a portion of the external surface of an aircraft. The drag reduction portion may include an inlet to ingest airflow. The aircraft may also have an internally cooled electric motor adapted for use in an aerial vehicle. The motor may have its stator towards the center and have an external rotor. The rotor structure may be air cooled and may be a complex structure with an internal lattice adapted for airflow. The stator structure may be liquid cooled and may be a complex structure with an internal lattice adapted for liquid to flow through. A fluid pump may pump a liquid coolant through non-rotating portions of the motor stator and then through heat exchangers cooled in part by air which has flowed through the rotating portions of the motor rotor. The drag reduction portion and the cooled electric motor portion may share the same inlet.

An aircraft propulsion system with a drag reduction portion adapted to reduce skin friction on at least a portion of the external surface of an aircraft. The drag reduction portion may include an inlet to ingest airflow. The aircraft may also have an internally cooled electric motor adapted for use in an aerial vehicle. The motor may have its stator towards the center and have an external rotor. The rotor structure may be air cooled and may be a complex structure with an internal lattice adapted for airflow. The stator structure may be liquid cooled and may be a complex structure with an internal lattice adapted for liquid to flow through. A fluid pump may pump a liquid coolant through non-rotating portions of the motor stator and then through heat exchangers cooled in part by air which has flowed through the rotating portions of the motor rotor. The drag reduction portion and the cooled electric motor portion may share the same inlet.

A method includes obtaining thermal energy from a structure to be cooled, where the structure includes micro-channels. The method also includes providing the thermal energy to a water-based polymer network, where the water-based polymer network includes a gel formed using a polymer and water. The method further includes generating one or more gases by heating the water-based polymer network, where generating the one or more gases includes releasing the water in the water-based polymer network to produce steam. In addition, the method includes passing the one or more gases through the micro-channels to remove at least some of the thermal energy from the structure.