The battery ran down sometime overnight. I pulled it out and it recharges ok. Last night, short press followed by long press, as I have done over the years would only result in two beeps and no shut down. When I continued this process and hold the power button longer, the battery light would start sequencing, running from one light to another. Looking at the controller I found the screen with the "pair aircraft" or something like that illuminated. I pressed that and continuous controller beeping would commence saying to hold down the aircraft power button for X seconds. After that, all seemed normal as in ready to fly, no alarms, no calibrations required.
So now let's shut it down, go to bed and fly tomorrow. No such luck. Did this over and over for almost an hour going back and forth with the scenario described above. Searched the forum for a similar problem and found nothing and so, here I am.
Until I can get it figured out, I'd just like to know; if I encounter this again, motors not running, only the fan, with aircraft powered on and I can't shut it downs, is pulling the battery a safe way to shut down?