True on the boomerang shape. it was in High School when I was in a class and we were making plywood boomerangs and our teacher was showing us the profile of each arm the boomerang had to take. it was obviously the boomerang is the same shape as any modern aircraft wing. ....and the mind blow moment was thinking we could have had aircraft flight thousands of years before it did...so many many years before. The knowledge was RIGHT! there but it was a very simple shift in thinking to turn the boomerang into an aircraft wing. Makes you wonder how many other discoveries are RIGHT there, in our faces but we need to take that one moment to think a little bit different to discover it.
