In reverse order...
Do you have loads of Ni-Cad batteries being swapped out because people leave the towing (or similar) switch on? If not why not?
No, because...
1. On all other a/c, the towing switch (if fitted) does not send battery power to operate the brakes. Just lights and radio.
2. Ni-Cads, if exhausted, can be rechargd on board the a/c. (Assuming there is enough wiggly amps left to get the ground power on or a seperate battery to start the APU.) The APU battery on a 787 also supplies lights during towing on battery.
I think this is a bit inappropriate, trying to stick it on the front-line staff at ANA and Japan AL (the two principal 787 operators so far, with more than half the total deliveries between them), and on their technical and training staff, for letting 150 batteries at USD 16k each go phut just by leaving a switch on. Remember this is a cutting-edge piece of critical kit, with every bit of software management known to engineering (supposedly) built all around it to keep it in good condition.
Don't get me wrong please. I lay any 'blame' if such exists, firmly at the door of Boeing for not labouring the point (IN LARGE RED LETTERS) during the initial (Boeing delivered) training courses.
It's certainly not something I remember being enforced during my course in Seattle.
Boeing train the airline trainers don't forget.
