Pie in the sky
I may have more to say on the DC sniper case later, in a new thread.
In the case F. 587, I'll concede your point that eyewitnesses may not always understand what they've seen.
True, instead of a car-size ball of flame near the right-wing root of F. 587, it could have been a big, red balloon, or an orange cloud, a red eagle, or just cherry pie in the sky. I guess there's an almost endless array of things which could have confused those eyewitnesses to F. 587's final seconds.
However, as the number of people reporting essentially the same thing at the same time rises, the possibility that they are all mistaken approaches zero.
sp