Was second on scene when H1 was a young PPL....a young lady had been decapitated 3 or 4 times over as she walked forward from the C177, rather than rearward, and the engine was still idling.
I didn't see the moment of the accident, but I heard a funny noise, turned, and saw the body and bits fall along with the associated arterial blood spray....not very nice, strangely enough we all have our weird ways of coping, I must admit to thinking at the time...I wouldn't want to have to clean that mess up
a bit disrespectful me thinks given the passage of time.
Second incident and very much more recently, I witnessed along with my little girl the final moments of the UPS 747F as it flew very low over our house in DXB at dusk, and impacted with a "crump" and a huge fireball about a mile from where we stood at the local playground.
That I think emotionally took a while to get my head around, its not everyday you see that kind of thing.
Thankfully I've been told I'm rather pragmatic, so I can rationalize the bad stuff.