Randall:
Question: Does a mechanic have to sign off on an ELT battery replacement, or can I replace it and sign it off?
Bob Steward, A&P-IA
For most ELTs it would be a simple job. The FAR 43 Appendix A subparagraph (c) list of items, that are allowable as “preventive maintenance” by the owner with at least a PPL, includes removing and replacing batteries.
It doesn’t specify “ship’s battery”, and in the spirit of the other tasks allowed, the stipulation is that as long as there is “no complex disassembly”, and that the “primary flight controls” are not tampered with, the owner can “change a battery”.
So in my opinion as an owner, a mechanic, and an IA, I say YES, you can remove the ELT battery to check its date, and if it is found to be defective, depleted, or out of date, you are allowed to put back in a new battery.
Do the log entry in the airframe log with the date the work was completed, total time in service of the appliance being worked on (airframe tach time), the name of the person doing the work, a brief description of the work, and your signature and certificate number. For example, “123456789 PPL”. I would also include the expiration date of the new battery as a courtesy to future owners and mechanics.
Editor’s note:
I also strongly recommend that you record any numbers you see while you have the ELT out of the plane. Most logbooks have a section near the front for “life limited parts”. You can also use this space to record things like the ELT manufacturer, model, serial number, TSO qualification, manufacture date, etc. Developing these detailed records may save you a lot of money someday, as well as making it more certain that you’ll get correct replacement parts (without the need for disassembly).