skadi,
I have lost count of the number of FOD incidents with the 135 over the years.
The screen is pretty large on the engines and the "change of direction" doesn't really exist. Everything that can pass the screen will.
On the otherhand, the airstream often changes direction, so that heavier objects will bypass the engine. They will leave the duct through the opening at the aft end of the dog house
No they don't.
I have maintained and flown the 135 now for about 12 years.