407 T/R Issues
During it's infancy, there were a number of accidents where the tail rotor made contact with the boom.
The solution was:
Lower VNE until real fix can be found. Lower IAS = Less Flapping.
Move tail rotor further from the boom.
And finally, add the pedal stop system, which is airspeed sensitive. Below certain airspeed, full pedal travel allowed. Above that airspeed, travel would be restricted to prevent gross inputs.
Story I always heard was that Bell assumed the "real problem" was pilots inadvertently slamming full pedal in at cruise. Use your imagination on the scenarios leading to that.
I flew the aircraft for 7 years in temperature ranges from +35 to -40 C and I never had any issues with the tail rotor or the pedal stop system.