Question for the techs: is it typical for transport aircraft to have all the generator control units and TRUs in one place?
The generator Control Units are on the same equipment rack, but they are quite far apart (two on each side of a rack which is maybe 3 metres across). The TRU's (AC to DC converters) are in a different area, but they use generator power.
Perhaps Boeing might consider putting a monitoring circuit on the drain mast heaters to sense failure (in their next gen aircraft)?
Is the problem really a maintenance issue... or a design issue. The problem is not really a "maintenance issue" if the heaters are routinely inspected every x months. A heater could fail the day after. How do you know when a light bulb will fail? Aircraft are not immune to the laws of physics (as some people think)
I wonder how many other airlines found cracked drip shields? They are not the most robust of things. I suspect all would find a few cracked shields if the inspections were done properly.