I believe that a Bell 205/212 lost a blade in the Philipines, aircraft flying in formation reported that the aircraft had "blown up".
A number of years ago a Hughes 500 was involved in a mid air with a Bell 47(Bristows)
in Kent.
The 47 blade got a bit mangled but the aircraft landed safely.
The 500 lost 9 inches off one blade tip including all the weights and went on to land with no casualties.
The damage to the 500 was substantial due to the vibration.
The instrument console sheared off at the base, and there was little structure left retaining the tailboom. It was possible to move the boom end up and down about 18 inches.
Tough aircraft!!!!!!!!!!!