The invention relates to a vane having a regulating flap (1) that can be moved between a retracted position and an extended position and a gap covering device (10) having an adjusting lever (13) and a gap covering flap (11) arranged thereon, having a flow surface (11 a), ° wherein the adjusting lever (13) having the gap covering flap (11) is prestressed by a prestressing device (20) into a first position in which the gap covering flap (11) is located in the interior (B) of the vane (F), and ° wherein the regulating flap (1) and the adjusting lever (13) having the gap covering flap (11) are coupled mechanically such that when the regulating flap (1) moves into the retracted position thereof, the adjusting lever (1) moves into a second position against the prestress produced by the prestressing device (20), and ° wherein the flow surface (11 a) of the gap covering flap (11) in the second position of the adjusting lever (13) runs between the top side (2) of the retracted regulating flap (1) and the vane flow surface (7).