I've read this thread (and AC 23-27) several times and I still can't make a decision.Summary & Disclaimer: This is not an "approved" replacement lamp by authorities, despite the fact that Cessna has abandoned FAA-PMA lamps for taillight fixtures and now lists a common automotive lamp for the tail nav light, and despite the fact the LEDs will meet/exceed light output while drawing incredibly lesser amounts of current and produce nowhere near the heat of incandescent lamps. Whelen now produces approved LED navigation lamps for aircraft should this experiment convince you as well as it did myself, to convert to LEDs. <EDIT> However Advisory Circular 23-27 provides the basis of approval for using automotive lamps in aircraft built before Jan '71. I have been using these in my airplane now for 2 yrs and am very satisfied with them. One should make a log entry to the effect that LED "standard part" lamps have been installed as direct replacements. IMO
If the LED lights are considered standard parts,
...and an aircraft owner is authorized to replace Nav lights
...does this mean that I can replace my Nav lights with the LEDs with nothing more than a log entry made by myself?
It doesn't seem like it should be that easy.
-David