I got my CD this year, and am hosting my first club event, our annual Big bird Fly in here in Waco this year,, as always Turbines are welcome,, but I have done some searching and can not seem to find any answer to my question about accepted sizing

usually for a big bird event the monowings are min. 80 inch wingspan, and biplanes are 1/3 scale or larger, However I can not find any info as to what dictates a " big bird jet' I know that my 1/6 f16 is a large jet, but the wingspan on it is about 66 inches from missile edge to missile edge, so technically it is not 80 inches. However I thought I read somewhere that the turbine jets were measured differently for such events, using length or scale,, I just cant seem to find any real info on what Is technically considered a "BIG BIRD" turbine jet for events... I know that some of you know the exact details,, Thanks fellas