My only experience with a tail rotor failure was as a passenger riding in the left front seat of a UH-1D Huey on a Battalion Admin flight to Saigon Hotel 3 helipad at Tan So Nhut AFB. I was merely hitching a ride for a short business trip to Saigon ( I am not at liberty to discuss what kind of business).
At the time I was a Chinook pilot assigned to the Battalion and had been qualified in the Huey during Flight School leading to my being dubbed an Army Helicopter Pilot.
We departed our base, bled just a bit of MR rpm but no problems, flew five miles to a second base.....picked up some fuel and a couple of SLF....and bled a bit of RPM on takeoff....still no problem. One might consider the earlier D Model Hueys were not known to be power houses with rotors...and as they aged and became assigned to duties such as the Battalion Log bird....they had some wear and tear on them. It was not unusual in operations to fly them down to just above LTE which was around 5800-6000 RPM N2. They had both a Low RPM warning light and a warning audio to warn the pilot. The light came on first....then at a lower RPM the Audio sounded.
We flew to Saigon....about twenty minutes away....and our stalwart pilot whose main duty was being the Battalion Mess Officer due to his piloting abilities falling a bit short of that required for use in operations....made his steep approach to a hover at the landing pad. Mind you the landing site was fairly confined on the surface but had no real obstacles demanding anything but a normal landing. Needless to say....operational pilots always landed to the ground when presented with a limited power landing to a nice flat concrete surface.
My Hero did not.
He stopped at a hover and several things happened at once....the first being me thinking "What is this guy doing?" I immediately thought he was confused as to where to park....and I began to point towards the transient parking to our left.
He turned right.
Wondering if he knew something I didn't....I suggested over the intercom the parking was now behind us. He kept turning right....and I figured he was just going to go the long way around and hover over to the parking pad. He didn't stop turning. All this was at or below standard rate of turn for such maneuvering.
I thought he saw a parking spot to the right of the aircraft.....he had not.
About this time....I noticed the left pedal was extended all the way forward and he appeared to be a bit tense looking and seemed a bit lost for something to say. The rate of turn began to build...and we passed by the parking pad direction at a fair old clip. I told him to cut the throttle as it plainly appeared to me that was the only cure for the situation extant.
He did not.
While looking at him...I noticed a bright red light on the panel....where the Main Rotor RPM light was on at about 1000 watts....a sly glance at the Rotor Tach confirmed the warning light was doing it's thing....we were at about 5700 RPM instead of the 6600 that was normal (N2 RPM).
Ah...I thought....this is not as it should be.
Not being astronaut material it still seemed I was correct in my advice....and again told him to chop the throttle....which he did not do....but now was eyes fixed firmly straight out front of the helicopter looking at the world revolve around him like his name was Sol.
Sol is not the name I would have called him as he definitely was not the brightest thing in the Sky.
We passed....or the parking pad passed us....depending upon how you wished to look at...but this time the rate of rotation was such that my aviator Raybans felt like they were going depart for foreign shores and I was rapidly increasing in weight. The world was becoming a blur!
I chopped the throttle....probably I could have told the Mess Officer about it ahead of time but I felt he might just figure it out for himself and if he didn't nothing worse could happen than was already coming our way.
He didn't figure it out on his own....but good Army training never fails one in time of need.
Magically, the rate of rotation steadied, slowed, and we found old Mother Earth and the H-3 landing pad. We slewed to a stop, made an instant low-low skid mod on one side. When I got my legs to quit wobbling...I thanked the Mess Officer for the great ride....un-plugged my Helmet....grabbed my Ditty Bag and departed for Saigon leaving the Mess Officer to deal with the Army since I was only a passenger on the flight.
Long story....but even though it was only a loss of Rotor RPM....and thus loss of Tail Rotor Thrust aggravated by trying to hover when over weight for the power of the aircraft....the forces that can be generated are hard to imagine. As the size of the aircraft grows so do the magnitude of forces. If one adds in the loss of tail rotor components and the resulting CG shift and aerodynamic forces....these events can very well be catastrophic.
Simulators can approximate some of the effects but not duplicate them....in flight practice cannot. Stuck pedal or loss of thrust maybe....but not loss of components.
I think the key is to use the Sim and Flight training to describe as best possible the initial reactions of the aircraft to educate the pilot for what to be able to react to when it happens.
To steal a motto...."Who dares....wins!" Very timely reaction to a tail rotor failure will help mitigate the situation but that requires being able to assess what is going on and then reacting properly. As Torque is the problem....reducing Torque is the best way to start. Lowering the collective all the way to the very bottom if possible is step one in the process followed by the Engine(s) next. (In my opinion.) After that I guess one plays the cards dealt to you.