To the best of my knowledge, the Storch was among the first, if not the first to use LE slats and it was pretty legendary in it's climbing ability. Supposedly, the Skyray was developed using German studies, I presume during the war years-it was a 50's era plane. As a Navy carrier plane, I guess they wanted all the T/O Lift and slow, high angle approach-so slats. That plane had a small retractable tail because it landed with such a high A/A. Do the present day jets (fighters) use slats? Seems like pix,etc. I recall show flaps. RWH: I think I recall an article way back about the Pharoh with regard to high lift devices. High T.E.K. Models, in CT had balsa slat material according to the '94 MAN article about slat const., don't know if they're still around.