Chris Scott
Only part of the solution would be not charging enroute. It is off handedly suggested by the rule, since this portion suggests the requirement is for minimum (state of) charge for launch, not inflight....
(8) Any lithium ion battery installation whose function is required for safe operation of the airplane must incorporate a monitoring and warning feature that will provide an indication to the appropriate flight crewmembers whenever the state-of-charge of the batteries has fallen below levels considered acceptable for dispatch of the airplane.
So this is a checklist item for
flightcrew pre launch.
Again, it seems counterintuitve that the rule would call for inflight charging (maintenance) in a
standby system. It does not imply that enroute charging is not allowed, but it could be read that way. NTSB has said the voltage of the
battery did not exceed its limit in the JAL accident.
It is hard to fathom that this was not considered long ago, I am sure it was. I would have lobbied for "no charging during flight", perhaps either side of wheels up by 30 minutes minimum. However, that implies charging enroute would need to be prevented, (defeated). If it was possible, some one would.
Technically, charging a standby system in flight is oxymoronic. If the batteries are on line, in an emergency, and the charger is active, the load is borne by the CHARGING SYSTEM, so why have standby batteries at all?
And begs the question I asked awhile back. If the Battery is on line, (under charge) and the draw is in any way variable, see below,
@ edmundronald.
