I'm getting really 'brave' with the ThreeDeeNT now, doing silly things like 1260 and 1620 stall turns, death spirals (those blades make lovely noises), and plenty of inverted stuff.
Trouble is, my tail stopped working around 5 minutes into the flight yesterday and I was hovering inverted over some long grass (no wind luckily). It wasn't really pirouetting that 'wildly' as the belt had come out the back end and was causing so much drag it almost looked 'graceful'. I tried briefly to 'flip' the right way thinking if I could get enough height, I would try an auto (hopefully the pirouetting would stop before I got too low) but as I've not 'progressed' to 'pirouetting flips' I was a bit uneasy and eventually decided to 'put her down' as gently as I could, bleading as much head speed off before the inevitable.
When I 'waded' into the location of the heli I was surprised at the minimal amount of damage, blades survived (that was a big load off the wallet) and the thing looked pretty much 'in-tact' so it was back to the pits to carry out the 'post-mortem'.
What we found was the flange missing from the tail drive pulley so there was nothing keeping the belt from tracking off! The fly-bar was pretty bent up, the horizontal fin 'flew off' in the middle of the drama (probably caused by the belt) and remains in the 'jungle' somewhere, the left cyclic servo gears had stripped, and later investigation proved the feathering spindle to be bent (main shaft survived though).
Got the bits to get it all back together again (apart from those damn servo gears) and will include the inspection of the pulley flange into the 'pre-flight' checks in the future (when was the last time you checked yours?).
I've read about people landing inverted without sustaining damage before but when faced with the situation I was not looking forward to inspecting the damage and would have thought a 'bin bag' would've been required when retrieving the remains, perhaps I was just lucky in this instance - maybe the long grass helped out (it's about chest height at the moment), not sure of much except I hope it doesn't happen again too soon - at least until I've learnt the pirouetting flip and emergency auto w/o tail drive