Lucy had another hockey tournament with her all girls team, the Atlanta Thrashers, so we flew over to Charleston's KCHS International airport/Air Force Base. Upon landing we saw tons of C-17 Globe Masters! We caught an Uber over to the rink to immediately start her first game while Brandi dropped our baggage at the hotel nextdoor and caught up with us shortly after.
Lucy's team played 4 games - one on Friday, two on Saturday, and one on Sunday. She's on a 12 and under team and about half the girls are around age 9 or so and often the opponents are towering over most of our players. The girls did great and played their hearts out and everyone improved and had fun as always. We enjoyed lunches and dinners with the other hockey parents and all too soon the tournament weekend was over so we headed to the airport to fly home.
20 minutes into our flight home we suddenly lost our primary alternator as our ammeter showed 0 amps being produced. We have 2 alternators and 2 batteries so we continued the flight home. I later ran through the BandC alternator troubleshooting guideline document by probing the regulator here and there, bus voltage, B and F leads on the alternator and everything seemed perfect. I scratched my head for a bit then decided to crank it up and sure enough bubbles was making amps! I went on a 15 minute test flight and all continued to be well so I guess bubbles self healed, which is great, but not too comforting. I suspected the crowbar over-voltage protection got tripped but had to re-read up on that module to remind myself excatly how it worked since it has been over 10 years since I was in the electronics trenches.
Ah, as I suspected "A crowbar circuit is distinct from a clamp in pulling, once triggered, the voltage below the trigger level, usually close to ground voltage. A clamp prevents the voltage from exceeding a preset level. Thus, a crowbar will not automatically return to normal operation when the overvoltage condition is removed; power must be removed entirely to allow the crowbar to return to its neutral state."
The crowbar protection seems to be the most likely explanation, however its unclear what caused the high voltage in the first place so I'll have to keep an eye on things and maybe do some more diagnostics. I checked the flight data log via Savvy and the voltage didn't get recorded as spiking super high, but the resolution of the logs probably was not quick enough to capture a brief spike.