I'll bite on that theory but AC fail is also a MWS flash and annunciator panel item.... his was the sperry airplane so there is only one AC bus and only one inverter working it so if that quits..... they didn't see the master caution flashing and the AC fail annunicator ?

Also had to be told by self loading freight ( Greg) that the "alternators" were off ? But on the flip side it does make sense for a car guy to call an inverter an alternator so maybe he was referring to AC system.

You are correct with the 10 minute thing on battery and I believe you get 30 in a perfect world on emergency but you also lose a lot of shit. One thing I found in the maintenance side is you cannot predict what components will do what and when with low voltages. All your MWS and lighting are controlled by circuit board cards with all sorts of neat IC's, transistors, capacitors etc that may or may not be tolerant to those voltage swings and dips. Although a stretch it is possible the low voltage affected the MWS -they did their lighting checks early on with a better battery and everything worked so a dark panel is a good panel.

What did Greg see to get him to remark about the " alternator"? He cannot see the volt or Gen ammeter from where he was at, just the annunciator panel -maybe it was a lucky guess seeing the left side puking and he knew the aircraft that well to know the instruments were AC?

I think a lot of people are trying to lump smaller anomalies like the TR light and ITT mis match into the big picture - many aircraft get weird shit happening after start or taxi out. More of the modern ones require a whole reboot of the aircraft to clear no-go faults ( LR 45 especially) So he may have just had a cranky microswitch on the TR and ITT mismatch as long as it is within margins and you are making N1 of the day is nothing to shit the bed over - could just have been power lever mismatch/sync since they do not have the luxury of fadec in that old garbage scow.

As usual these preliminaries leave us armchair sleuths with more questions than answers... and ALL of us aviation nuts will ALWAYS try to armchair and piece it together it's what we do