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I was tasked to conduct an air test on a Wessex at RAF Odiham in the late 70s. Before I was due to lift, I had to conduct a Blade Track. This involved the engineers erecting a vertical pole, with tripod legs and steady wires, just outside the rotor disc, and then slowly rotating a canvas flag into the rotor tips. The tips had coloured chalk on the ends, so the flag would be marked with the tip paths (eg red blade up 1 inch, yellow down 2 etc).
Ac starts normally, all functionals completed, and I signal to the engineers to move the mast into position. The three of them push the heavy mast towards disk, to line up the tripod feet with chalk marks on the ground. Unfortunately, they hadn't noticed a step in the join between adjacent concrete slabs. One foot snags on that and, as the engineers keep pushing, the top tips over towards the rotor disc, and one of the steady wires contacts the tips.
Sudden twang, ac now vibrates, and emits a loud whistling noise as the four rotor tips are ripped off!
So I shut down, trudged back to the line office, to sign the ac in, and complete an incident report.
A wire strike, having never left my parking space, with zero flight time.