Grob G 102 Astir CS prototype with turbulator Tape under the wing
Malte Höltken (<a href="https://en.wikipedia.org/wiki/de:User:Pwd" class="extiw" title="w:de:User:Pwd">Pwd</a> at <a href="https://en.wikipedia.org/wiki/de:" class="extiw" title="w:de:">German Wikipedia</a>)
CC BY-SA 3.0
<span class="int-own-work">Self-photographed</span>