High and Flighty/FAA said
'...That'll be bad news if all four of the GCUs aboard a 787 were powered up at the same time, because all will then shut down, “resulting in a loss of all AC electrical power regardless of flight phase.”>>
But normally there is a few second or minutes between start of one engine and the second engine. And then the APU will be shut off after climbout . Which then leads to the following
One engine GCU times out and shuts of its two generators. No biggie- other engine and APU can easily carry the load. But a few minutes later, 2nd engine generator system cuts out . Oh well we still have APU to start engines ? Then an few minutes later, the APU generator times out ??
Or is the GCU involved a single point join so that its timer overloads - and the battery system cuts in with ' nearer my god to thee ' ??
