Perhaps you’re in the same situation that I’m in. Every time I do an avionics upgrade I watch my ammeter needle creep up a notch. At what point do my alternator and voltage regulator just give up the ghost and fail? Back in 1977 when my airplane was built there wasn’t a computer or display screen anywhere to be found in my plane. In fact, the smallest computer you could get took an entire room to house. And now? I counted 13 computers in my plane.

So how are we going to get some of that power usage down without turning off my expensive avionics? We’re going to do it the same way we do it at home. We’re going to replace incandescent light bulbs with LED bulbs. These new bulbs use a fraction of the power that the old bulbs did, run cooler, and will last forever. In fact, they should last the life of the plane.

First, you’re going to have to buy your replacement bulbs. Aircraft Spruce and other sources have them. Whelen Aerospace Technologies is a good resource if you want to go directly to the manufacturer. Aircraft Spruce has a light bulb section, and you can pick these out very easily. I’ll put the part numbers that I used below. My airplane is 12VDC and so I’m picking 12V bulbs. If your plane is 24V, you’ll need different bulbs. Choose wisely!

The bulbs we’re going to replace are as follows:

Wing tip position lights:
11-07512 12V Green LED bulb, $34.75 each
11-09299 Clear lens, $15.65 each

Landing gear panel lights:
11-09629 white LED bulb, $6.95 each

Rotating beacon:
Pick for your airplane, $633 to $761

Landing light:
11-12976, $274.95

These are all as easy as pie to replace and so I’m going to keep the article short and put the directions with each picture. When it’s done, I’m sure you’ll see your ammeter move downward. And you’ll never have to buy another light bulb, either. Good luck!

Right wing tip light with green position light and strobe before disassembly. Remove the screw while holding the lamp in place. If you don’t hold it, the strobe and position light covers will fall and shatter.
The new green LED bulb with the position light powered up.Have you wondered why we got a clear lens above to replace the green lens below? The old incandescent bulb is clear and requires the green lens. The new LED bulb is already green and if you use the old cover you’ll attenuate the light too much.
The position lamp can be pushed in slightly and rotated about an eighth of a turn counterclockwise. It will pop out when you release pressure. If the strobe tube is black (like mine is getting), there won’t be much life left in the bulb. Get some rubbing alcohol (isopropyl) and put a few drops on a clean, soft cloth and clean the strobe. Be gentle, they’re expensive.
I removed a landing gear bulb from my panel by pulling the unit straight out. It was tight and I had to rotate it back and forth a bit before it came out. The unit I’m referring to is the green bulb holder on the bottom of this picture. Above are two bulbs. The left bulb is the old incandescent bulb and on the right is the new LED bulb. Push the new bulb into the green gear unit and reinsert the unit back into the panel.