Many moons ago, on a small island in the Caribbean, a Bell 212 was being tracked with the pole & flag method. Things went a little awry when the flag was gently moved into the path of the blades. One rotor blade contacted one of the metal tangs to which the springs were attached stretching the canvas flag between the two tangs. The pole was smacked sideways and the two engineers attending the flag were rather shaken.
The helicopter was immediately shut down in order to inspect for any damage to the rotor blades. All eyes were focused on the blades as they slowed down, nobody was aware that in a corner of the hardstanding, an engineer ( I think it was the local chief engineer) was laying in a pool of blood having been cut severely, high up on his inner thigh by the piece of metal that flew away from the tracking pole.
Thankfully, somebody spotted him in time and appropriate medical attention was given.
I can't remember whether the blades were damaged, but this episode just goes to prove that the this method has some hidden dangers!
Somebody else on this forum may have a better memory of this than me?
F43