A process for operating an air jet spinning machine having at least one spinning station comprising a vortex chamber, - wherein a fibre strand is fed during a spinning process to the vortex chamber in a spinning direction, - wherein the fibre strand receives a twist inside the vortex chamber with the aid of an airstream, so that a yarn possessing the twist is formed from the fibre strand, - wherein the yarn having the twist is drawn off from the vortex chamber with the aid of a draw-off device, - wherein the yarn drawn off from the vortex chamber is monitored for yarn faults by means of a yarn monitoring device arranged downstream of the vortex chamber characterized in that the spinning process is interrupted when a yarn fault is detected in such a way that the yarn detaches itself from the fibre strand and a yarn end forms, and that subsequent to the interruption of the spinning process, a piecing process, at least partly carried out by the spinning station is initiated, in which the following steps are carried out: - suctioning of the yarn end with the aid of a first suction unit of the spinning station in the area between an outlet opening of the vortex chamber and the draw-off device, - cutting the end section of the yarn containing the yarn fault in the area of the first suction unit with the aid of a yarn cutting unit of the spinning station. - returning the yarn end of the remaining yarn opposite to the spinning direction through the vortex chamber with the aid of an air stream generated by at least one air injection nozzle, which air stream is directed in the vortex chamber, or respectively, a draw-off channel through which the yarn passes, of a yarn forming element projecting into the vortex chamber - seizing of the yarn end in the area of an inlet opening of the vortex chamber - preparing the yarn end for an attachment of the yarn end to the end section of the fibre strand, - putting into operation of the draw-off device - superimposition of the yarn end still located outside of the vortex chamber to the end section of the fibre strand, - joint drawing in of the yarn end and the end section of the fibre strand into the vortex chamber, - resumption of the spinning process by continued feed of the fibre strand into the vortex chamber and drawing-off of the yarn formed in the vortex chamber. - wherein a fibre strand is fed during a spinning process to the vortex chamber in a spinning direction, - wherein the fibre strand receives a twist inside the vortex chamber with the aid of an airstream, so that a yarn possessing the twist is formed from the fibre strand, - wherein the yarn having the twist is drawn off from the vortex chamber with the aid of a draw-off device, - wherein the yarn drawn off from the vortex chamber is monitored for yarn faults by means of a yarn monitoring device arranged downstream of the vortex chamber - suctioning of the yarn end with the aid of a first suction unit of the spinning station in the area between an outlet opening of the vortex chamber and the draw-off device, - cutting the end section of the yarn containing the yarn fault in the area of the first suction unit with the aid of a yarn cutting unit of the spinning station. - returning the yarn end of the remaining yarn opposite to the spinning direction through the vortex chamber with the aid of an air stream generated by at least one air injection nozzle, which air stream is directed in the vortex chamber, or respectively, a draw-off channel through which the yarn passes, of a yarn forming element projecting into the vortex chamber - seizing of the yarn end in the area of an inlet opening of the vortex chamber - preparing the yarn end for an attachment of the yarn end to the end section of the fibre strand, - putting into operation of the draw-off device - superimposition of the yarn end still located outside of the vortex chamber to the end section of the fibre strand, - joint drawing in of the yarn end and the end section of the fibre strand into the vortex chamber, - resumption of the spinning process by continued feed of the fibre strand into the vortex chamber and drawing-off of the yarn formed in the vortex chamber.