Landing light brightness/landing and/or taxi lights

birdus

birdus

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Jay Williams
I recently bought a Luscombe. During night-time taxiing, I can hardly see, so I bought a couple Whelen Parmetheus Plus Landing lights ((P36P1L). I figured they'd give me blinding brightness.

Turns out the incandescent lights these were meant to replace are brighter at idle (a possible condition during landing). At power, say 1,800 RPM, the LED is only just as bright as the incandescent. Very disappointing. I have a few questions.

1) Is there something I need to add to the system to get full brightness out of these lights at idle? My friend suggested a voltage regulator.
2) If I get much brighter taxi lights, will they be as effective at distance as these dimmer landing lights, although give me better situational awareness around the plane?
3) Or, should I get one landing light and one taxi light?
4) Or, would bright enough landing lights give me adequate brightness near the plane due to reflections off the ground?

Regardless, I want brighter lights, so I'm going to have to get different ones. Maybe the P46 would be a good alternative. The price is still reasonable.

Thanks,
Jay
 
HID are the brightest out there so far. LED’s are getting better and better through. Advantage with both HID and LED is that they draw significantly less power than the antique Incandescents.


Sent from my iPhone using Tapatalk
 
birdus said:
I recently bought a Luscombe. During night-time taxiing, I can hardly see, so I bought a couple Whelen Parmetheus Plus Landing lights ((P36P1L). I figured they'd give me blinding brightness.

Turns out the incandescent lights these were meant to replace are brighter at idle (a possible condition during landing). At power, say 1,800 RPM, the LED is only just as bright as the incandescent. Very disappointing. I have a few questions.

1) Is there something I need to add to the system to get full brightness out of these lights at idle? My friend suggested a voltage regulator.
2) If I get much brighter taxi lights, will they be as effective at distance as these dimmer landing lights, although give me better situational awareness around the plane?
3) Or, should I get one landing light and one taxi light?
4) Or, would bright enough landing lights give me adequate brightness near the plane due to reflections off the ground?

Regardless, I want brighter lights, so I'm going to have to get different ones. Maybe the P46 would be a good alternative. The price is still reasonable.

Thanks,
Jay
Click to expand...


Hmm, you sure you’re making the correct amount of voltage at the landing light? Might want to poke it with a multimeter
 
birdus said:
During night-time taxiing, I can hardly see, so I bought a couple Whelen Parmetheus Plus Landing lights ((P36P1L)
Click to expand...
FYI: landing light bulbs are different than taxi light bulbs due to a different lens. And they are adjusted differently. So if the lights are not adjusted properly it won't matter how bright the light is.
birdus said:
so I'm going to have to get different ones.
Click to expand...
FWIW: Throwing money at a problem without checking for underlying issues, especially with electrical problems, usually ends up costing you $500 for a $10 fix.
 
How are the bulbs pointed. Usually in a tail dragger, you'll want one pointed at a negative angle so that it illuminates the ground while three pointed.
 
No way an incandescent should be brighter. Especially in low rpm ops. The battery should easily power the LEDs even when the charging system is idling.
 
You don't have lighting issues, you have power TO the light issues. My Parmetheus is ten times brighter and wider than the incandescent it replaced.
 
Make sure you have 12 volt lamps and not 24 volt models. I have seen that happen.
 
  • The LEDs are the 14-volt models (P36P1L)
  • Both the incandescent and the new LEDs were pointed appropriately for us to see the brightness on the ground. (I left one of the incandescents installed along with a new LED in the other wing for testing.)
  • The voltage tested today at 11 volts at idle. It only went up to 13 volts at 1,800 RPM. Measured at the light.
  • This plane has a generator. It's a C-85.
 
birdus said:
  • This plane has a generator. It's a C-85.
Click to expand...


Take one of these and call me in the morning

https://www.aircraftspruce.com/catalog/eppages/planePowerSAL_07-01321.php

07-01321.jpg



The Don Luscombe Aviation History Foundation, Inc.
8E; 8F; T-8F
STC SA10921SC
Alternator model ER14-50
https://planepower.aero/product/aircraft-generator-to-alternator-conversions/

for chits and giggles, take some jumper wires and hook it up to your car battery, guessing that will make a yuge difference
 
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When I swapped in a Prometheus I expected it to light up half the runway where the old incandescent bulb seems to dimly light up a few hundred feet or so. The Prometheus did light up more runway and definitely is whiter/bluer color but it is not "way brighter". This is for a 14volt landing light (its not the wide beam taxi light - verified). So I think it's a winner for lower power and bulb life but maybe only like 20% brighter.
 
Sinistar said:
When I swapped in a Prometheus I expected it to light up half the runway where the old incandescent bulb seems to dimly light up a few hundred feet or so. The Prometheus did light up more runway and definitely is whiter/bluer color but it is not "way brighter". This is for a 14volt landing light (its not the wide beam taxi light - verified). So I think it's a winner for lower power and bulb life but maybe only like 20% brighter.
Click to expand...

I got a noticeable upgrade when I swapped my 24v landing and taxi out for these

https://goodiesforpilots.com/par-36-new

I had their older model, little less $$ and there was a landing and a taxi model, worked great!


Compare GE vs LED photo from my swap
https://www.pilotsofamerica.com/community/threads/cheap-led-landing-taxi-lights.107577/#post-2440262
 
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Sinistar said:
When I swapped in a Prometheus I expected it to light up half the runway where the old incandescent bulb seems to dimly light up a few hundred feet or so. The Prometheus did light up more runway and definitely is whiter/bluer color but it is not "way brighter". This is for a 14volt landing light (its not the wide beam taxi light - verified). So I think it's a winner for lower power and bulb life but maybe only like 20% brighter.
Click to expand...

This was my experience, but only at higher RPMs, and then only maybe a hair brighter. I took one of the incandescent bulbs home and hooked it up to a car battery charger. It was WAY brighter. It was even brighter than the LED when I ran the LED off of a power supply at 13-14 volts.
 
Seems like this might just be the answer.

James331 said:
Take one of these and call me in the morning

https://www.aircraftspruce.com/catalog/eppages/planePowerSAL_07-01321.php

07-01321.jpg



The Don Luscombe Aviation History Foundation, Inc.
8E; 8F; T-8F
STC SA10921SC
Alternator model ER14-50
https://planepower.aero/product/aircraft-generator-to-alternator-conversions/

for chits and giggles, take some jumper wires and hook it up to your car battery, guessing that will make a yuge difference
Click to expand...
 
birdus said:
  • The voltage tested today at 11 volts at idle. It only went up to 13 volts at 1,800 RPM. Measured at the light.
  • This plane has a generator.
Click to expand...

A generator won't do anything at idle. The voltage regulator has a reverse-current cutout relay that prevents loss of battery capacity backwards though the generator when its output voltage falls below the battery voltage. That relay in your regulator might be inop, or all the other stuff you have turned on is drawing the battery voltage down at idle. Shut off that remaining incandescent light and the nav lights and see what the LED brightness and voltage does. And make sure your voltmeter is accurate. One other possibility is dirty cable connections at the battery or bus; any resistance there will lower the system voltage when the generator isn't producing. The master contactor is another likely spot for resistance. They get old and burned out too.

If you're doing a lot of night flying, get an alternator. Makes a huge diference.
 
Battery volts should be around 12.5 with any decent battery at idle after charge. Incandescents couldn't draw it down that far in a short period of time. I think it's time for a battery capacity check with a loadmeter.

What is the bus voltage at, say, 1800 rpm or so? That Prometheus ought to be blinding, not "just a little bit better".

Jim
 
A alternator should be one of the first upgrades to a plane with a gen, and that’s coming from someone who used to have a older gen equipped plane
 
weirdjim said:
What is the bus voltage at, say, 1800 rpm or so? That Prometheus ought to be blinding, not "just a little bit better".

Jim
Click to expand...

I'll repeat what I said elsewhere in this thread for your convenience. When hooked up to a power supply at my house, the Prometheus was a particular brightness at 13-14 volts. When hooked up to a car battery charger, the incandescent was at least as bright. I thought that was interesting. My power supply didn't appear to be able to supply adequate amperage to the incandescent; thus, the battery charger.

Jay
 
My PAR36 LEDs were way brighter than the incandescents they replaced, even when running only on the battery. I just had a plane power alternator installed as well; recommended.
 
GeorgeC said:
My PAR36 LEDs were way brighter than the incandescents they replaced, even when running only on the battery. I just had a plane power alternator installed as well; recommended.
Click to expand...
Just to clarify...you swapped in PAR36 LEDs...but not specifically the Prometheus ones? I think my taxi LED is just a PAR36 LED (but not Prometheus, will be remedied soon) and I think it is noticeably brighter than the incandescent.

I wanted to think the Prometheus was way brighter but to my eyes it's just a bit brighter and a much more pleasing color...which does not make it brighter.
 
GeorgeC said:
My PAR36 LEDs were way brighter than the incandescents they replaced, even when running only on the battery. I just had a plane power alternator installed as well; recommended.
Click to expand...

Ordered the alternator yesterday. :)
 
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