Missing a few feet of wing in the pictures, for sure, but
that doesn't mean that it happened in flight, nor that it flew that
way. I've seen similar pictures of aircraft damaged that way on the
ground by trucks or other aircraft, or even by bad landings in strong
crosswinds. Even taxying too close to a signpost at excessive speed
could do it. The end of the wing is badly mashed and would present huge
drag and really serious controllability problems.
Let's see:
Mashed left wingtip, massive drag requiring all the
rudder he has, maybe not enough at that.
Loss of lift from mashed wing section (disturbed airflow)
requiring extra lift from aileron, which itself is a third gone
Loss of lift because part of wing is missing, meaning
more aileron required. Those ailerons simply can't make up the
difference.

And nobody noticed. Right.

The engine is probably a Soloy conversion, more
common on 206s. An Allison turbine set up to drive a prop.

Dan