I found a reference to the Canadian anti-gravity experiments in the 1980s, done by a fellow named John Hutchinson. For some reason, the Canadian government seized all his equipment, some of which was using Nicolas Tesla inventions. Tesla also had his equipment and notes seized by the U.S.A. government back in the 1940s. Someone may not want these experiments done (the U.S.A. fed explanation was to keep it out of the hands of the Nazis).
http://www.nottaughtinschools.com/John-Hutchison/Antigravity-Lab.html
The Hutchison effect also discredited, is not anti-gravity, but a type of electromagnetic wave effect based on wave frequencies of objects. Oh well.
https://www.youtube.com/watch?v=TIqIT9avewU