My black lab used to sleep in the chin bubble of the 206. Had to make sure his claws were well clipped to preclude scratching the bubble.
Some dogs are bothered by the tail rotor on some helicopters - Hughes 500s seemed to attract them. A friend of mine landed a 500 at a fishing lodge once and some mutt ran out onto the pad and with a mighty leap "attacked" the tailrotor. Things went badly for the rest of the day.
I am sure that some of the guys who work with avalanche rescue dogs and suchlike will have lots of usefull info.