I will never dispute that the common UOA can spot wear. Especially if you have a trend to watch. We use the simple tests for helicopter main transmission oil. Iron clearly shows up when wear is becoming a problem.
Here is a typical UOA from our heli main gearbox:
Iron 0.5, Copper 0, Nickel 0, Chromium 0, Silver 0 , Magn 0, Alum 0, Lead 0, Silicon 0.7, Titanium 0.2, Tin 0, Moly 0, H2O 1200.
In this case, when iron gets to about 15PPM, the gears are wearing abnormally.
Here is a typical UOA from our heli main gearbox:
Iron 0.5, Copper 0, Nickel 0, Chromium 0, Silver 0 , Magn 0, Alum 0, Lead 0, Silicon 0.7, Titanium 0.2, Tin 0, Moly 0, H2O 1200.
In this case, when iron gets to about 15PPM, the gears are wearing abnormally.