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