Have I seen things I can't explain? Yep. Do I know what they were? Nope. The problem is the human brain wants to "fill in the voids" and make things "make sense", so beyond seeing something you can't explain, things go south pretty fast when reading these stories or hearing them from other people. One only has to go back to TWA 800 and the absolutely crazy conflicting stories told by eyewitnesses. It's a classic case for the unreliability of witnesses and how our mind will "make up" information to make things more palatable for us, to make it more emotionally comforting or to assign some kind of "reason" for it. It's extremely hard to sort through the BS in these cases usually because we "want to believe", even on a subconscious level.