Hi Ruediger,

there is a drawing from Grob, specifying the turbulator location for the single-seaters as follows (distances measured on the pressure side of the wing from the trailing edge to the trailing edge of the tape):

Wing root: 360mm
Inboard end of the aileron: 300mm
Wing tip: 178mm

Twin I and II twoseaters receive the tape only at the ailerons with the following dimensions:
4300mm from the wing tip: 380mm
Inboard end of the aileron: 370mm
Wing tip: 208mm

Unfortunately, these locations are not included in the service letters from LTB Lindner.

The tapes do not significantly improve the performance - perhaps 1 or 2 points, you won't notice that. But they remove the seperation bubble from the ailerons and improve the airflow there. You will notice that the glider becomes more stable in a turn. You will also need less aileron input for corrections and the aileron in general is a bit more responsive.

Best
Christoph