Several decades ago in Borneo,I had a tail-rotor blade depart,followed by the other one and the t/r gearbox.The day had started with a troop lift to various LZs,and whilst landing to refuel,someone pointed out `something` under the aircraft,Ilifted off and moved away,revealing a large pool of oil on the ground,so parked,shutdown and inspected it.It was a broken transfer oil connection between the engine and reduction g/box. Short story ,called `home` ,who sent a standby aircraft and groundcrew ,who whipped out the engine/gbox and replaced the bit,whilst the other crew finished my task.A/C ground -run,so we set off as a pair to RTB,,with a couple of the mechs downstairs with an access panel removed to check if it was all OK at the back of the g/box.As we climbed,I checked down in the cabin to get a `thumbs-up `(no intercom) from the lads,when there was an almighty `Bang`,the aircraft yawed hard right,and pitched nose down.Pedalling produced no response,and the stick was on the back stop,to prevent it pitching further.I thought I had collided with the other aircraft,as I couldn`t see it,and had gone into autorotation instinctively about 800ft, looked for a place to land,as I had no idea of further damage,thinking I had collided,and put out a couple of `Maydays`,just in hope..As we were over a mix of primary and secondary jungle,I saw what appeared to be a small clearing,and continued a right spiral towards it,closed the HP cock,and flared as much as I could,finding that the area was actually a `small` hillock,or pimple,and then EOL`d at zero speed,but finding we were on about 10-15 deg slope.The mechs were OK,strapped in,and the only other damage was a burst tyre from a tree stump ,that was stopping the a/c from rolling off...Shortly after,the other aircraft appeared,and winched us out.The Board of Inquiry offered the local Headman,and villagers money for any bits they could find,and the blades and g/box were recovered a week later.It was found to be a fatigue crack in the threads of the blade spindle that had caused it,but it had taken some time to propagate.
Throughout the incident,I had poor roll control,probably due to a lowish speed 50-60 kts,and limited cyclic f/aft,but that may have improved as the mechs `down below` went aft to strap in.I don`t recall any yaw on touchdown,probably because the undercarriage was caught in the secondary ground foliage.
The aircraft was lifted out,and repaired at base,and the following day one of the other pilots gave me a USAF Flight Safety magazine, with an article about `How to handle t/rotor failures in the H-34!
There`s a pic or three on P15 of `Rotorheads around..Cockpit views`,#294...