Aircraft wing trailing edge closing device, aircraft wing and aircraft wing drag reduction method

The invention relates to a trailing edge closure device for an aircraft wing, comprising: a linkage mechanism configured to be hinged to a first hinge point on a rear spar; an actuating element hinged to the flap and connected with the linkage to actuate it; the blocking mechanism can be hinged to a second hinge position point on the rear beam and is connected to the connecting rod mechanism; when the flap moves from the closed position to the unfolded position, the flap drives the actuating element to actuate the connecting rod mechanism, so that the connecting rod mechanism rotates around the first hinge position point and the blocking mechanism rotates around the second hinge position point, and therefore the blocking mechanism can close the wing fixed trailing edge structure. Therefore, after the flap is put down, the fixed trailing edge of the wing can be automatically closed, a smooth gap between the flap and the fixed trailing edge structure of the wing is formed, and air flow flowing through the front