Maxtork,
I agree. Sitting under a gearbox that I know will run for 30 mins dry on a bench would not make me happy in the knowledge that it would run dry in an aircraft for 30 mins. I don't know how they do bench testing but to be valid in my opinion, they have to account for thermal stress from engines and cooling effects of airspeed, torsional and bending moments imparted by the airframe, engines, controls, rotor head, tail rotor drive and of course the effects of aging/fatigue. I don't think that that kind of detail can be replicated on a bench. Am I wrong?
So much emphasis these days are placed on Cat A performance (rightly so) and yet is it me or has the regulation of gearboxes and drive train not kept up? Or is it that now we are putting so much power through gearboxes, the regulations haven't accounted for how close we are to the viable technological limits?
It is the FAA and JAA/EASA that need to be looking at their belly buttons.