A deployable flap hinge includes a flap part (2) corresponding to a flap (A). The flap part (2) has a flap upper part (4) and a flap lower part (5), a body part (3) corresponding to a vehicle body (B), a first joint assembly (6) connecting the flap part (2) and the body part (3) in an articulated manner, and a second joint assembly (7) connecting the flap upper part (4) and the flap lower part (5) to one another in an articulated manner. The flap upper part (4) can be swivelled relative to the flap lower part (5) between a resting position and a deployed position. The deployable flap hinge also includes a locking assembly (40) for locking the deploying movement of the flap upper part (4), and a pretensioning device (10) for pretensioning the flap upper part (4) in the direction of the deployed position. The pretensioning device (10) includes a pretensioning element (11) formed as a single piece from a part of the flap hinge (1).