CABIN DOOR LOCKING MECHANISM FOR HELICOPTER

The present invention provides a cabin door locking mechanism for a helicopter, comprising: an outer handle assembly, an inner handle assembly, a lock box assembly, and a lock seat assembly. The outer handle assembly comprises an outer lock plate, an outer handle, a button, a first swing arm, a first spring shaft having a first spring, a tension spring, and a second swing arm. When the outer handle is unlocked, the outer handle automatically rotates outward by an angle under a transmission action of the tension spring pulling the first swing arm, and thus can be conveniently held by an operator; when the outer handle is held and continues to rotate outward, the outer handle drives the second swing arm to rotate to pull a steel wire rope, thus enabling the lock box assembly to be unlocked from the lock seat assembly; the inner handle assembly comprises an inner lock plate, an inner handle, and a second spring shaft; the second spring shaft can be driven by the inner handle to drive the second swing arm to rota