Much thanks for all the good info and photos of those beautiful boomers. It was a bit surprising that you credited the circular inertia to gyroscopic properties but didn't give any credit to the Magnus Effect for either lift or flight-path. I also had no idea that boomerangs had such a long history. Given the similarity between the typical boomerang airfoil and those of the NACA in the 1930-1940s it's hard to believe manned flight was first achieved without a solid mathematical foundation.