Ifresh, I had an experience several years ago with an R22 that I hired to pick up my pals son, as a birthday treat.
My usual actions on SFH was to check the Tech Logs to see who had previously been out, and what if anything was to report about the Heli, seemed the last one out was a young pupil pilot (H) and a reasonable proficient ( but not yet fully qualified Fi) the tech log was written up seemed OK and no mention of any problems.
I went out and did my walkround,crawl under, climb on and checked everything I could see touch and fondle(in machinary terms ) fueled up and went through the start up proceedure, evrything seemed to be A1 and OK to go, so after permission I lifted and hover taxied to take of into wind, doing that meant I was going to be flying towards the almost full tide, almost at its full height and depth, cleared to go by the tower I proceeded to do what most pilots do and that was to start the bird going and increasing power to attain t/lift, just at the point were lift was aquired I started to feel a stiffness in the stick, at this point I was clearing the perim at about 200ft with the wind and speed lifting me rapidly higher, I requested an immediate return to land , this was granted, what happened next was a total shock to me for I found I could not turn left, and the stick was starting to violently shake to the point that I found I could not risk lifting my thumb to use the radio button, I could not turn sharpe right for two reasons the R22 wouldnt respond but I would have been over private dwellings and public areas, I considered landing in the sea but due to the wind I could see some huge waves and quickly lost the want to land in the water, the tower was aware of my predicament and cleared the airspace for me to try any way back, after a very careful and "green area " flight I managed by turning right only to get back to the field to use the vast expanse of outfield and the service there on offer to bring this stricken R22 back down with as much smoothness as I could muster, at this time I can say to you I was exhausted, the stick had been occilating so much and so fast that I was unable to feel my hands or fingers I had two hands on the stick to use the radio button to inform the Twr of my plans and told them I would not speke again until I was down, they were brilliant they kept telling me they were watching me and could see exatly where I was in relation to the field,. to cut a long and boring story short, I found that as I came down to the point of being just 20/30 ft from the grass area I had picked and below T/lift speed the violent occilations ceased, so down I sank and stopped the engine.
Being an ex farmer and steel worker I consider myslef pretty strong, but that occilation on the stick could not be controlled by my bulk fighting to control it.
All this was caused because said earlier trainee Fi, had allowed his student pilot to overspeed by a massif amount I was eventuall told it was about 125/130% whilst showing said pupil what a full EOL would feel like, but the FI never owned up or entered this fact into the Tech log, for if he had I would not have flown that Heli.
However I started then to examine my own ways of doing my preflight and asked many very experienced pilots and engineers what I could have done to find that problem which was badly stretched main rotor bearinds and or housings due to the massif O/speed, their answers were, I would not have seen anything on a pre-flight check, and the only way was to rely on honesty of previous Fi's or pilots.
Since that day I have not flown any Robinson R22's simply because if I had used my massif bulk and strength to stop the occilation something else more serious would have broken.
I am sorry for such a long winded story, but you must rely on your ability to do the pre-flight as well as total and absolute honesty of the previous flyers, Many people up here in this part of Lancashire know who I blame for the diabolical record keeping of that heli.
My regards
Peter R-B
Vfrpilot Pb