An unmanned aerial vehicle (UAV) has an air-cooled fuel cell, an air channel comprising a forward facing opening for receiving ram air and connected to the air-cooled fuel cell, and a passive ram air filtration system (PRAFS) configured to filter particulate matter from ram air received into the air channel via the opening.

An unmanned aerial vehicle (UAV) has an air-cooled fuel cell, an air channel comprising a forward facing opening for receiving ram air and connected to the air-cooled fuel cell, and a passive ram air filtration system (PRAFS) configured to filter particulate matter from ram air received into the air channel via the opening.

Braking systems for aircraft are disclosed. An example braking system includes a fan cowl having a leading edge and a trailing edge. The braking system includes a hinge assembly coupled between the leading edge and a fan cage of an aircraft engine to enable the fan cowl to move between a stowed position and a deployed position. An actuator is coupled to the leading edge of the fan cowl, and the actuator is to move the fan cowl via the hinge from the stowed position to the deployed position in a direction away from the aircraft engine and toward a fore end of the aircraft to provide an air brake during a braking event.

A strake for a turbine engine nacelle may comprise a forward portion coupled to a turbine engine nacelle inlet, and an aft portion coupled to a turbine engine nacelle fan cowl, wherein the aft portion is configured to move between a first position and a second position, and the aft portion engages the forward portion in response to the aft portion moving to the second position to secure the fan cowl with respect to the inlet.

A strake for a turbine engine nacelle may comprise a forward portion coupled to a turbine engine nacelle inlet, and an aft portion coupled to a turbine engine nacelle fan cowl, wherein the aft portion is configured to move between a first position and a second position, and the aft portion engages the forward portion in response to the aft portion moving to the second position to secure the fan cowl with respect to the inlet.

An aircraft nacelle arrangement includes a compression rod disposed between a first nacelle half and a second nacelle half, wherein the first nacelle half and the second nacelle half are rotatable about a hinge between a closed position and an open position, a compression rod disposed between the first nacelle half and the second nacelle half, and a mounting bracket coupled to an exhaust nozzle flange of the aircraft engine, wherein the compression rod extends through the mounting bracket.

An aircraft engine nacelle for coupling to a wing of an aircraft is disclosed having a fore end, and an aft end that is immoveable relative to the fore end. The aft end includes a major axis Mj and a minor axis Mi, and the nacelle is configured such the minor axis Mi is closer to vertical V than the major axis Mj when the nacelle is coupled to the wing and the aircraft is stationary on the ground. An aircraft system and an aircraft are disclosed each including the aircraft engine nacelle.

An aircraft engine nacelle for coupling to a wing of an aircraft is disclosed having a fore end, and an aft end that is immoveable relative to the fore end. The aft end includes a major axis Mj and a minor axis Mi, and the nacelle is configured such the minor axis Mi is closer to vertical V than the major axis Mj when the nacelle is coupled to the wing and the aircraft is stationary on the ground. An aircraft system and an aircraft are disclosed each including the aircraft engine nacelle.

An aircraft nacelle is disclosed and includes a first fan cowl and a second fan cowl. An opening is defined in an exterior surface of the first fan cowl. The aircraft nacelle also includes a blade, a latch mechanism, an arm, and a linkage assembly operably connecting the arm to the blade. The blade is moveable along between a stowed position and a deployed position. The latch mechanism is moveable between a latched position an unlatched position where a portion of the latch mechanism obstructs a path of movement of the blade. The arm is unable to move from an extended position where a portion of the arm extends through the opening in the exterior surface of the aircraft nacelle into a retracted position within an interior volume of the aircraft nacelle when the blade is in the deployed position and the latch mechanism is in the unlatched position.

A fastener assembly may comprise a housing defining a first cavity and a second cavity. A first threaded member and a second threaded member may be located within the housing. A first biasing member may be coupled to the first threaded member. A second biasing member may be coupled to the second threaded member.