Wow.
May I ask what aircraft (glider) those TG-37 and TG-103 are?
Yes the Diamond HK-37 Super Diamona and the Grob G 103 Twin Astir. Those are used in the flight introduction courses which are accessible for all how pass the written selection, being gliders help the finances of the air force (the towing aircraft are rented from a private specialized company) and also teach the young pilots the basic of the flight, hoping they will never glide again...