Abstract: A seal assembly for sealing the slot formed between the aft end of an extended leading edge flap and the leading edge of a wing includes a flexible, blade-type seal extending spanwise between the leading edge flap and the wing. The upper end of the seal is attached to the underside of the leading edge flap adjacent its aft end and extends downwardly therefrom. The bottom portion of the seal is normally spaced from the leading edge of the wing. The seal is flexible so that when air is flowing over the leading edge flap and the wing, airflow from the underside of the flap causes the lower end of the seal to move toward the leading edge of the wing and intimately engage the leading edge of the wing in sealing contact. After the bottom edge of the seal engages the leading edge of the wing, the differential pressure between the upper surface of the flap and the wing and the region below the leading edge flap maintains the seal in contact with the leading edge.