Drakkar,
I rather doubt that any negative G was actually involved, possibly close to zero G though. The manoeuvre off the rock wasn't severe enough to induce it.
Having displayed the military Puma "semi-aerobatically" some years ago, I am very aware that on this type of aircraft the hydraulic pumps can cavitate if even reduced +G is experienced. Such as at 120 degrees nose down at 450 feet agl.... which doesn't half wake the crewman up.
Ask my crewman (now SAR pilot) 'Dark Menace' about the chinagraph pencil he bent whilst sat in the LHS and supposedly writing with it!
