Alternator failure flying home from Thanksgiving

[lr172]

Originally Posted by dmattmul

This my electrical display on the G3X. Any thoughts on adding a master warning (Red alarm) or master caution (Yellow alarm) to a led in plain sight on the panel? (Future RV-10 in progress)

There are ground sink connections for both master warning and master caution. Run 12V to an led (12V style, not stock LEDs) or incandescent lamp and then to these pins and you will have annunciation lamps. Best if the 12V source comes from the dimmer buss.

Larry

[Bavafa]

Glad you made it home safe and thanks for sharing the LESSONS

[avrojockey]

Great write up, great job IMO...lessons learned.

I have and electric dependent IFR bird and decided on a IBBS and isolatable Essential Bus...no backup alternator. The design involved a bunch of load research. I was surprise how little amperage the G3X LRUs pull. The biggest draw was going to be the COM during transmit, I decided to leave this out as I carry a handheld backup. I have the small TCW IBBS (3ah) and it lasts 1-hour with all screens on bright, IAW their CA docs ...that means a healthy 16ah PC680 should last over 5 hours or fuel exhaustion.

[RV7A Flyer]

Originally Posted by Ed_Wischmeyer

Pleasant phone call and email (below) from the FAA. They’re just doing their follow up. The lady who called is from the maintenance side. I’ll pull the cowling later today and see if there’s something obvious.

The following notification by the Regional Operations Center was received by the ATL FSDO: SAVANNAH, GA (SAV): N7152Y, RV9A, REPORTED ELECTRICAL PROBLEMS AND CONTINUED TO SAV. LANDED WITHOUT INCIDENT. 11/26/2022 1727Z
In order to close the occurrence, we are requesting the following information:
1. A signed written statement of events from the Pilot in Command (PIC)
2. A copy front and back of the PIC’s airman certificate with current medical
3. A copy of the maintenance record entry returning the aircraft to service
I can be reached by email with any questions.

You should probably also file an ASRS, just to cover all the bases.

[rv7boy]

Originally Posted by RV7A Flyer

You should probably also file an ASRS, just to cover all the bases.

Already done. See last two lines of OP’s first post.

[Bavafa]

Originally Posted by avrojockey

Great write up, great job IMO...lessons learned.

I have and electric dependent IFR bird and decided on a IBBS and isolatable Essential Bus...no backup alternator. The design involved a bunch of load research. I was surprise how little amperage the G3X LRUs pull. The biggest draw was going to be the COM during transmit, I decided to leave this out as I carry a handheld backup. I have the small TCW IBBS (3ah) and it lasts 1-hour with all screens on bright, IAW their CA docs ...that means a healthy 16ah PC680 should last over 5 hours or fuel exhaustion.

Just a reminder that if IBBS is wired per diagram, if/when the alternator fails, then the primary battery will be feeding the avionics with electron if the pass thru have been wired unless you have a way of isolating/shutting down the pass-thru. The end result of this would be that if you are expecting your main battery is your reserve and to work after the IBBS, that may not be the case.

[RV7A Flyer]

Originally Posted by rv7boy

Already done. See last two lines of OP’s first post.

Ah, yeah, I missed that. Was reading the OP late, late last night, so just blazed right on by that. Anyway, a good reminder that it can never hurt to file one.

[Ed_Wischmeyer]

Pulled the cowling. Fan belt appears okay, no obvious loose/broken wires. Time to call in the A&Ps…

[BruceW]

What make of alternator, please ???

[Walt]

Originally Posted by BruceW

What make of alternator, please ???

I'm willing to bet it was either an auto unit or PP?