On Tuesday, December 11, 2018 at 8:24:51 AM UTC-6,
Here is a beautiful, over 50 year old film made by the National Film Board of Canada featuring some of the top performing gliders of the day (Std. Austria SH-1, Sisu and HP-11).
https://www.nfb.ca/film/flight/
Any idea which Sisu went to Canada and then came back?
Steve Leonard