I remember when they called the first diamond distance length task at the open national in minden. It was on the longest daylight day of the year, I think it was 1977 or 78. All I remember is the triangle sent them way out to Austin NV. My bro was one of the few 15 meter ships flying that contest and made it home (zuni). I was glad since I was the crew and them zuni wings were heavy lol.