Yep, another Plane Power thread. Alternator has been in service for 8 years and about 1000 hours, it's an AL12-EI60/B from before PP was bought up by Hartzell.
Out flying around today trying to get above the smoke when the alternator warning light flickered, then came on steadily. I started watching the voltage, but it didn't drop. Ranged between 13.9 and 14.1 volts, as it has done since new. Not only that, but it appears to be charging still. The current was fluctuating from approximately +5 to -2, but it's been doing that since new as well, after the initial startup surge.
Gave up on getting above the smoke (9500' wasn't enough) and descended back to the airport. I noticed the light flickered a couple of times, but generally stayed on steadily. I have an AFS AOA system with the nice lady inside that reminds me through the audio panel that I'm getting too slow with "angle angle push!." This time when the message came through I noticed what I would describe as a classic alternator whine, but only while the warning was being transmitted. Otherwise there was no audio noise.
I don't mind replacing the alternator if it's warranted, but I'm curious as to what would cause this. For the record I haven't decowled the engine for a look yet. That's next.
Thoughts?
Out flying around today trying to get above the smoke when the alternator warning light flickered, then came on steadily. I started watching the voltage, but it didn't drop. Ranged between 13.9 and 14.1 volts, as it has done since new. Not only that, but it appears to be charging still. The current was fluctuating from approximately +5 to -2, but it's been doing that since new as well, after the initial startup surge.
Gave up on getting above the smoke (9500' wasn't enough) and descended back to the airport. I noticed the light flickered a couple of times, but generally stayed on steadily. I have an AFS AOA system with the nice lady inside that reminds me through the audio panel that I'm getting too slow with "angle angle push!." This time when the message came through I noticed what I would describe as a classic alternator whine, but only while the warning was being transmitted. Otherwise there was no audio noise.
I don't mind replacing the alternator if it's warranted, but I'm curious as to what would cause this. For the record I haven't decowled the engine for a look yet. That's next.
Thoughts?