Vintage Friedlander?

Hardly! Rex Heflin was a California highway inspector who shot an interesting series of photos in 1965 with his job related Polaroid. Computer analysis of the original prints have detected no apparent forgery or manipulation of any kind, and match perfectly with Mr. Heflin's account of relative size and distance of said object. Three shots within twenty seconds, a feat easily recreated by a former Polaroid executive.

Now here's the question even I could figure out. A fourth picture he took just minutes later, of the "smoke ring" it left behind when he emerged from his pick up, revealed a highly detailed, cloudy sky very much different from the first three. Easily explainable, or proof of hoax?
Technical data: Polaroid Model 101,114 mm focal length, variable aperture, built-in light meter, automatic settings; Type 107 black & white film, ASA 3000.