The present disclosure provides various embodiments of a multicopter-assisted launch and retrieval system generally including: (1) a multi-rotor modular multicopter attachable to (and detachable from) a fixed-wing aircraft to facilitate launch of the fixed-wing aircraft into wing-borne flight; (2) a storage and launch system usable to store the modular multicopter and to facilitate launch of the fixed-wing aircraft into wing-borne flight; and (3) an anchor system usable (along with the multicopter and a flexible capture member) to retrieve the fixed-wing aircraft from wing-borne flight.

The present disclosure provides various embodiments of a multicopter-assisted launch and retrieval system generally including: (1) a multi-rotor modular multicopter attachable to (and detachable from) a fixed-wing aircraft to facilitate launch of the fixed-wing aircraft into wing-borne flight; (2) a storage and launch system usable to store the modular multicopter and to facilitate launch of the fixed-wing aircraft into wing-borne flight; and (3) an anchor system usable (along with the multicopter and a flexible capture member) to retrieve the fixed-wing aircraft from wing-borne flight.

The present disclosure provides various embodiments of a multicopter-assisted launch and retrieval system generally including: (1) a multi-rotor modular multicopter attachable to (and detachable from) a fixed-wing aircraft to facilitate launch of the fixed-wing aircraft into wing-borne flight; (2) a storage and launch system usable to store the modular multicopter and to facilitate launch of the fixed-wing aircraft into wing-borne flight; and (3) an anchor system usable (along with the multicopter and a flexible capture member) to retrieve the fixed-wing aircraft from wing-borne flight.

The present invention discloses an unmanned aerial vehicle including a main body, a plurality of arms, a propulsion assembly and a battery assembly, where each arm is coupled to the main body and the propulsion assembly is disposed on the each arm. The battery assembly is accommodated in a battery compartment of the main body. The battery assembly includes a shell, a battery body substantially disposed in the shell, a clamp button, and a restorable elastic piece. An end of the clamp button is mounted or connects to the shell, and the other end of the clamp button is detachably coupled to the main body. An end of the restorable elastic piece is disposed on the shell or connect to the shell, and the other end of the restorable elastic piece contacts the clamp button.

The present invention discloses an unmanned aerial vehicle including a main body, a plurality of arms, a propulsion assembly and a battery assembly, where each arm is coupled to the main body and the propulsion assembly is disposed on the each arm. The battery assembly is accommodated in a battery compartment of the main body. The battery assembly includes a shell, a battery body substantially disposed in the shell, a clamp button, and a restorable elastic piece. An end of the clamp button is mounted or connects to the shell, and the other end of the clamp button is detachably coupled to the main body. An end of the restorable elastic piece is disposed on the shell or connect to the shell, and the other end of the restorable elastic piece contacts the clamp button.

An undercarriage unit is provided. The undercarriage unit comprises: a rotatable wheel; at least one electromagnet for releasably coupling the undercarriage unit to the aircraft; a switch for selectively activating and deactivating the at least one electromagnet; and a controller arranged to actuate the switch. An aircraft having the undercarriage unit is also provided.

The present disclosure provides various embodiments of a multicopter-assisted launch and retrieval system generally including: (1) a multi-rotor modular multicopter attachable to (and detachable from) a fixed-wing aircraft to facilitate launch of the fixed-wing aircraft into wing-borne flight; (2) a storage and launch system usable to store the modular multicopter and to facilitate launch of the fixed-wing aircraft into wing-borne flight; and (3) an anchor system usable (along with the multicopter and a flexible capture member) to retrieve the fixed-wing aircraft from wing-borne flight.

The present disclosure provides various embodiments of a multicopter-assisted launch and retrieval system generally including: (1) a multi-rotor modular multicopter attachable to (and detachable from) a fixed-wing aircraft to facilitate launch of the fixed-wing aircraft into wing-borne flight; (2) a storage and launch system usable to store the modular multicopter and to facilitate launch of the fixed-wing aircraft into wing-borne flight; and (3) an anchor system usable (along with the multicopter and a flexible capture member) to retrieve the fixed-wing aircraft from wing-borne flight.

A rotorcraft together with a heat dissipation structure for a motor are provided. The motor includes a body and a revolving shaft driven by the body, and the heat dissipation structure for the motor includes: a casing being a hollow structure having a top opening and an air inlet in a bottom portion, in which the body is disposed inside of the casing, and an air channel is formed between a circumferential edge of the body and an inner wall of the casing; a head cover connected to the revolving shaft of the motor synchronously and provided with a plurality of air flow picks on the lower surface thereof; and a mounting stand fixed to an upper surface of the head cover.

A rotorcraft together with a heat dissipation structure for a motor are provided. The motor includes a body and a revolving shaft driven by the body, and the heat dissipation structure for the motor includes: a casing being a hollow structure having a top opening and an air inlet in a bottom portion, in which the body is disposed inside of the casing, and an air channel is formed between a circumferential edge of the body and an inner wall of the casing; a head cover connected to the revolving shaft of the motor synchronously and provided with a plurality of air flow picks on the lower surface thereof; and a mounting stand fixed to an upper surface of the head cover.