Surfing the internet I found some UPA animation art that is up for sale. The site had these concept drawings but they could not confirm what cartoon they came from except to say that they are from a WWII era industrial short.
My personal thoughts just by looking at the drawings is that they could be from John Hubley‘s Flat Hatting, which is a training film that was used by the US Navy. The films aim was to teach navy pilots about flying safety and that they should not buzz the people on the ground by flying too low or what is known as flat hatting in military speak.
Of course this is just an educated guess on my behalf, as I have never seen Flat Hatting. Amid Amidi posted Flat Hatting last year on Cartoon Brew TV, but it has since been removed. UPA made numerous training films for the military during the war, as did all the other cartoon studios.
These drawings are up for sale on the Van Eaton Galleries website, with prices ranging from US $25 – $100, which is pretty reasonable.