There also was teo production 21' hull that carried two different numbers that was called "my flying machine". The pictures shows a #21 named "my flying machine" and other pictures shows a #31 "my flying machine". It may be the same boat re-numberd or may be a second hull built I don't know but when you look at the race results just because it says #31 that dose not mean it was the pure race 25' hull. It could of be either one the 21' or the 25' hull. The "my racing machine" #31 only carried that one number far as I know. You may know more on this Sandy than I do with your FL resources, I would like to know more about this and the years each numbered hull ran and why the change. I always thought the #21 was the 21' hull and when he went to #31 it was the 25' hull, but proof below shows differently.
Both boats below are cut down production 21' hulls clearly named "my flying machine" but they carry two different numbers:
