I remember when I was at Chambers one of the local crews chopped up some firewood settling into Peanut (a small CAL zone perfectly shaped for our tandem rotors) and they were fine.PhrogLoop can probably provide better stories, but I've heard of Phrogs taking messenger lines for the RAS through the arc and rappel lines that have gotten wrapped up on the pitch change rods (or links or whatever the phrog called the connections from the swashplate to the blades).
One time I was FCF'ing in the Gulf of Aden and our rear drive arm link (scissor assembly) came apart because of a missing cotter pin through the bolt after the retention nut. The aft rotor system literally settled onto its own pitch links bent to about 70 degrees instead of vertical so the aft blades went to 3 degree pitch and unresponsive. My classmate and copilot was at the controls at 70 kts /300 ft and we went uncommanded nose up and he jammed the cyclic almost into the instrument panel with no response. It must have looked like an agressive quick stop from the boat (we were 3 miles in port delta) and we started falling ass first toward the Gulf. I remember 45 degrees nose up and increasing when I took the controls, and bottomed the collective hoping we could settle into ground effect which we did...at 20 feet. We bounced around for a few seconds and my crewmen asked "WHAT THE F WAS THAT!?" and announced that they had been strapped in with the emergency egress windows gone by the time we started settling. We creeped back to the boat at 200 feet/40 knots (couldn't get any higher or faster) and got the emergency straight in to spot 8. Landed, shut down, and kissed the flight deck.
I love that ugly, leaky, smelly, underpowered battle ax because she brought me home.