LED Landing Lights

[Colonel Sanders]

This is so simple to understand, yet so many people
struggle with the grade-school arithmetic required
to understand it.

[GyvAir]

I thought LEDs were on/off. Does a lower voltage affect the brightness of the light?

Watch the light output of your handheld LED flashlight as the batteries dip below their optimum voltage.

Penny wise, pound foolish as the saying goes.

That's a tough concept to get through to people on almost any investment.

[CpnCrunch]

$200 is kind of ridiculous when you can get an incandescant landing light for under $10

Oh I see it differently.... Letting alone the possible inconvenience of the single landing light quitting just when I need it most landing into my home runway, The time it takes to change the bulb, the need to maintain a spare in stock and the cost of alternator drive couplings worn by high alternator loads easily exceeds $200. I'd rather spend the money on the LED, and save the risk, inconvenience and work!

It doesn't take too long to replace a landing light and it's pretty easy to keep a few spares.

As for the alternator: you have the landing light on for about 30 seconds or a few minutes drawing 18 amps, whereas the starter motor draws 50+ amps every time you start the engine (with some people cranking away for 30 seconds every time they start because they don't believe in priming

The inconvenience of it quitting when you need it is definitely a good reason.

[ahramin]

I thought LEDs were on/off. Does a lower voltage affect the brightness of the light?

Watch the light output of your handheld LED flashlight as the batteries dip below their optimum voltage.

That's why I was wondering. I've got three, and all three put out the same amount of light until they quit. Maybe it's these fancy new LEDs.

[PilotDAR]

As for the alternator: you have the landing light on for about 30 seconds or a few minutes drawing 18 amps, whereas the starter motor draws 50+ amps every time you start the engine

It's not quite like that. The alternator is doing nothing while you're starting the engine, it's only after the engine is running it takes up a load. If you battery is in good shape, and you start crisply, the alternator is not working hard at this point.

When you flick on the landing light in cruise flight (or takeoff) the engine is operating at a decent RPM, and the alternator carries the load normally. "Normal" for the alternator is "normal" operating RPM for the alternator, and a load within it's capacity. The electrical load on the alternator becomes mechanical load to the engine, through the drive, and sacrificial coupling (belt in some cases).

Load equals RPM times torque. If the load remains the same (lots, 'cause you have all the lights on for night flying), and the RPM is reduced (on final) the torque must go way up. The alternator has no way to reduce load, or torque, or increase RPM on its own. Well, except for quitting. So, there you are coasting down final with everything on, and the alternator carrying huge torque. It you slip a alternator drive belt to carry that huge torque, that's not too bad. If your engine has a gear drive alternator, the coupling takes the abuse. If you have a front mount alternator Continental 520, overloading and slipping that coupling can get to be very expensive. O-200's are somewhat better, but still have a coupling which is expensive.

In my 150, prior to LED landing light, I would turn off the alternator before I switched on the landing light on approach, and turn it back on once the landing light went off, to top off the battery. Now, I don't worry about it - 2 amps!

[GyvAir]

Maybe it's these fancy new LEDs.

Good point. It's not just the LED itself, but the associated control circuit. A lot of LED flashlights operate at a voltage regulated to lower than the battery voltage, thus are able to maintain 100% light output until the battery voltage starts to drop off significantly. Some also have protection circuitry built in to prevent over-draining the rechargeable batteries and possibly damaging them. I've noticed modern li-ion powered power tools stop dead when the voltage drops below a threshold, rather than slowing down nowadays, taking more of the battery management out of the hands of the user.
I’ve never observed any aircraft LEDs under less than full voltage to see how they act.

It may take 5 minutes to change a lamp on some aircraft – with a running start. i.e. you’re already at the aircraft, you’ve already made the purchase of the replacement, signed it out of stores or retrieved it from storage, found the appropriate tools, waited for the exhaust manifold to cool down enough to reach past it to do up the wires, and nothing went sideways on you (no burnt or twisted off ring terminals, worn out/lost fasteners, etc)

[Colonel Sanders]

It takes about 5 mins to replace a landing light

What if you're on a deserted, dark ramp, 100 (or 1000)
miles from home, with no spare or tools?

You can't legally take off, if you have pax. So, you're
stuck there overnight. Plenty of time to think about all
the money you saved on a sh1t filament bulb.

[sidestick stirrer]

"The alternator is doing nothing while you're starting the engine"

Well, nothing GOOD at that point.

"the starter motor draws 50+amps"

I thought it was in the neighborhood of 300 amps and even more for the lightweight, high-torque units...

[MCB]

I came across an interesting issue regarding these LED lights.

Recently, an aircraft had returned after flying in icing conditions. The landing light was completely covered with ice as the LED lights generate no heat compared to the old style bulbs. I'd hate to be coming in at night with lights that are completely glazed over...

[howard40]

Has anyone done a side by side test of 12 volt landing lamps say whelen and alphabeams?
I want to buy one or two for the plane but dont want everyone telling me I bought the wrong brand. to replace my 4509's
what frikkin brand to buy?

this was the advice in 2010 has it changed? from Aviation consumer
Conclusion

We like these products and even though they’re expensive, we think they deliver value through their longevity, flexible beam width and favorable color temperature. Because they’re so much more expensive than conventional incandescents, we think the right way to look at them is as always-on recognition systems that double as landing lights, not the reverse. Even if you fly only in daylight, these products deliver benefits. If you fly under 50 hours a year, justifying the expense might be a reach.

Our top price-is-no-object pick is the AeroLED SunSpot, since it’s bright and includes a flasher. If we’re going to have LEDs, we want the flasher option. The Laminar Flow is a good pick, too, but it isn’t in production yet. The best value option without a flasher? Hands down, it’s Whelan’s Parmetheus. It’s a good performer at a reasonable price and its small size means it will fit any mount.


Thanks

[flying4dollars]

We have them on the B1900 fleet, including the taxi light. They took some time getting used to but I still don't like them any better. They aren't much brighter than the original lamps at their max light output. It also doesn't put off the natural light that the old ones did and I find night landings are no better with LED's than with the conventional bulbs. Now, HID would be pretty cool

General aviation might benefit, sitting lower to the ground probably makes a big difference in seeing the runway better as opposed to having them fitted on the inboard wing fairly aft of the cockpit.

[skymarc]

These are from Aeroleds and they are bright. I just put a 4" on my TBM on the nose taxi light and its brighter than the 250 w it replaced. I had Lopresti HID on the wings for landing lights and they were the best but I had to remove them as they were interfering with the G600 magnetometer. I will be installing an higher wattage Whelens which are about 25% brighter than the 250 w incandescents.

I also replaced the navs and strobes with the new Whelen Orions Leds and they are really brighter than original.

I had Parmateus Whelens on a Baron and it was brighter than the incandescent also.
The bright white light just makes it brighter and easier to see.

Got them on the Basler -- so far I'm impressed --- the DAK had good head lights and these work just as well or better and with the pulse function are very highly visible in the terminal area and can run continuously.

[skymarc]

Yes I did try the Whelen vs Alphabeam on a Baron.
The Whelens were brighter side by side. No comparaisons.
I did have an issue with the Alphabeam that it fogged up with water in rain. I took it out and its sitting hear on my desk waithing to replace it next time im at Spruce.

The brighter ones are Aeroleds and they are PMA. I think every new models are brighter every year and cost will come down.

Has anyone done a side by side test of 12 volt landing lamps say whelen and alphabeams?
I want to buy one or two for the plane but dont want everyone telling me I bought the wrong brand. to replace my 4509's
what frikkin brand to buy?

this was the advice in 2010 has it changed? from Aviation consumer
Conclusion

We like these products and even though they’re expensive, we think they deliver value through their longevity, flexible beam width and favorable color temperature. Because they’re so much more expensive than conventional incandescents, we think the right way to look at them is as always-on recognition systems that double as landing lights, not the reverse. Even if you fly only in daylight, these products deliver benefits. If you fly under 50 hours a year, justifying the expense might be a reach.

Our top price-is-no-object pick is the AeroLED SunSpot, since it’s bright and includes a flasher. If we’re going to have LEDs, we want the flasher option. The Laminar Flow is a good pick, too, but it isn’t in production yet. The best value option without a flasher? Hands down, it’s Whelan’s Parmetheus. It’s a good performer at a reasonable price and its small size means it will fit any mount.


Thanks