LED replacements for these C150G wingtip position lights?

[Pedals2Paddles]

Yes. Those look like the older version that PSA produced. I was looking at their newer ones:
http://www.aircraftspruce.com/catalog/elpages/ledreplacement11-12241-4.php

I'm not sure you finding one that fell apart is indicative of everything they sell. I have not seen a documented pattern of them falling apart. In fact I've seen only rave reviews. Have you established a pattern the rest of us haven't seen yet?

 

[philiplane]

I don't have photos but these suffer the same problem. The LED's come off the board. There are fewer of them so each one that falls of cuts the light output significantly.

Seems to be worse on aluminum wing tips, and on fiberglass tips where people omit the gasket between the lamp body and the tip. Operation on grass strips doesn't help either. Any plane that exhibits wingtip vibration (like Piper Warriors) will shorten the life of these lamps.

Plain circuit boards are not made for environments with low frequency vibration. Which is basically airplanes, heavy equipment, and locomotives. In my designs for those applications, I use vibration isolation to resist the resonant frequency and keep the board from self-destructing. There isn't physical space in a standard nav lamp assembly to do this.

Incandescent wingtip lamps use a reflector to shape the light output so it can be seen equally across the field of view. LED's do not. They are extremely directional, emitting light in a concentrated beam, straight out. That is why these aftermarket lights use so many LED's. To approximate the coverage you get with a reflector, that LED's cannot use since no one has invented a surface mount LED and circuit board with a built in reflector. When one LED dies, you lose the light output from that direction. Meaning you can have the light very visible from dead on, but not more than a dull glow from another angle. Since people use position lights to see which way a plane is moving at night, you really don't want any dead spots.

Here's what goes into a nav lamp, beacon, or strobe design to meet FAA standards:http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/0/0410ab09b4a7057d862569ae006d35d1/$FILE/AC20-74.pdf

 

[Pedals2Paddles]

When one LED dies, you lose the light output from that direction. Meaning you can have the light very visible from dead on, but not more than a dull glow from another angle. Since people use position lights to see which way a plane is moving at night, you really don't want any dead spots.

And the alternative, is when one incandecent burns out, you have no light at all in any direction

 

[Kiddo's Driver]

Doesn't matter whether it's a light bulb or a crankshaft. If it's not certified you can't use it on a Type Certificated plane.

add "without a field approval" to your sentence and I would agree with you.

Edit: I should have finished the thread before posting. This is covered in detail already.

 

[txflyer]

Christ Almighty. I put those LED bulbs in mine and never noticed they're not PMA'd.

Throw me in prison.

 

[ahkahn]

Christ Almighty. I put those LED bulbs in mine and never noticed they're not PMA'd.

Throw me in prison.

Not sure about you, but I'd rather get written up for making a mod on the plane that enhances safety for myself, passengers, and the people on the ground than getting written up for something that compromises the safety for myself, passengers, and people on the ground.

In the research I've done, there have been far more onboard fires generated by an incandescent bulb than an LED. In fact, haven't found any LED-related onboard fires.

 

[txflyer]

Not sure about you, but I'd rather get written up for making a mod on the plane that enhances safety for myself, passengers, and the people on the ground than getting written up for something that compromises the safety for myself, passengers, and people on the ground.

In the research I've done, there have been far more onboard fires generated by an incandescent bulb than an LED. In fact, haven't found any LED-related onboard fires.

I agree. And they sure are perty!

 

[philiplane]

But when you get a Friendly Aviation Advisor checking your plane on a ramp check, and he gets interested the cool LED lamps in your stock nav light housings, how will you defend yourself? Remember, he has the power of the federal gubmint behind him, and you have shaky (really, you have no data) data to say these are Approved Parts. You can hand your pilot certificate to him for insertion into his portable shredder... over a light bulb.

 

[bnt83]

position lighting effects everyone in the NAS operating at night yet there is no regulation saying EAB airplanes need an approved system. I've talked to a whelen rep in the past who believed they must be.

"Incendecents burn out" many aircraft have two on each wing, just not GA airplanes.

 

[bnt83]

But when you get a Friendly Aviation Advisor checking your plane on a ramp check, and he gets interested the cool LED lamps in your stock nav light housings, how will you defend yourself? Remember, he has the power of the federal gubmint behind him, and you have shaky (really, you have no data) data to say these are Approved Parts. You can hand your pilot certificate to him for insertion into his portable shredder... over a light bulb.

Flashing ones are a dead givaway.

Airplane comes in with LEDs for annual and leaves with the bulbs in a ziplock bag replaced with original part # bulbs. Leds reinstalled by owner next day.

 

[txflyer]

..to any FAA people on here ..

But when you get a Friendly Aviation Advisor checking your plane on a ramp check, and he gets interested the cool LED lamps in your stock nav light housings, how will you defend yourself? Remember, he has the power of the federal gubmint behind him, and you have shaky (really, you have no data) data to say these are Approved Parts. You can hand your pilot certificate to him for insertion into his portable shredder... over a light bulb.

I double double checked, and mine are PMA'd.

Not like I said before.

 

[RyanB]

A little late on this post, but just now seeing it in the top threads. A 172 from the FBO and school I fly at has an LED landing light and its super! Very bright and easily seen from a good distance.

 

[bnt83]

A little late on this post, but just now seeing it in the top threads. A 172 from the FBO and school I fly at has an LED landing light and its super! Very bright and easily seen from a good distance.

Cert requirements for landing/taxi lights are nothing like position lights. Basically as long as they don't pose a hazard to crew and manufactured to a standard of some kind it's good to go.

Position lights are very specific about patterns, intensities and overlapping beams etc.

 

[philiplane]

Cert requirements for landing/taxi lights are nothing like position lights. Basically as long as they don't pose a hazard to crew and manufactured to a standard of some kind it's good to go.

Position lights are very specific about patterns, intensities and overlapping beams etc.

Landing lights have specific beam height and width specs that define the difference between the two different functions. Landing lights usually project a trapezoidal pattern about 12 degrees in width by 6 degrees tall.

Taxi lamps will have 14-20 degrees of horizontal spread and 5-9 degrees vertical spread.

I learned all of this minutia doing the certification for HID landing lights for aftermarket STC's.

 

[jesse]

Those look like basically the exact same nav lights I have on my Flybaby and I have LED bulbs. I can look at the PN next time. Of course it's doubtful the PN would be legal on your airplane. Not a problem for me though.

 

[bnt83]

Landing lights have specific beam height and width specs that define the difference between the two different functions. Landing lights usually project a trapezoidal pattern about 12 degrees in width by 6 degrees tall.

Taxi lamps will have 14-20 degrees of horizontal spread and 5-9 degrees vertical spread.

I learned all of this minutia doing the certification for HID landing lights for aftermarket STC's.

Title 14: Aeronautics and Space
PART 23—AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES
Subpart F—Equipment

§23.1383 Taxi and landing lights.
Each taxi and landing light must be designed and installed so that:

(a) No dangerous glare is visible to the pilots.

(b) The pilot is not seriously affected by halation.

(c) It provides enough light for night operations.

(d) It does not cause a fire hazard in any configuration

 

[philiplane]

Title 14: Aeronautics and Space
PART 23—AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES
Subpart F—Equipment

§23.1383 Taxi and landing lights.
Each taxi and landing light must be designed and installed so that:

(a) No dangerous glare is visible to the pilots.

(b) The pilot is not seriously affected by halation.

(c) It provides enough light for night operations.

(d) It does not cause a fire hazard in any configuration

While those are the specs for operation, the manufacturing specs are more detailed. We have to follow existing data in FAA Advisory Circulars, or existing PMA specs. That is where beam spread, depth, and intensity are found.

Glare and halation are addressed in the beam characteristics, and can also be mitigated by use of light fences or lamp shields. The half-shield you see on Piper Cheyenne tip tank lamps, and Piper 6X nose gear mounted lights, are designed to prevent halo effects during high moisture (fog or night rain) conditions. Wide spread lamps obviously have more issues with pilot glare than narrow beams. The small fence-type shields you see on the wingtips of a Cessna Citation II through V, just inboard of the recognition lamps, are designed to prevent halation. Increasing the beam intensity by using an HID in place of the stock halogen lamp required a narrow beam spread to avoid increasing the fence by 2 inches in height and 3 inches in length. Increasing the fence size would have brought the wingtip design back into the ACO for engineering review and delayed the STC by 2 years.

 

[bnt83]

While those are the specs for operation, the manufacturing specs are more detailed. We have to follow existing data in FAA Advisory Circulars, or existing PMA specs. That is where beam spread, depth, and intensity are found.

Glare and halation are addressed in the beam characteristics, and can also be mitigated by use of light fences or lamp shields. The half-shield you see on Piper Cheyenne tip tank lamps, and Piper 6X nose gear mounted lights, are designed to prevent halo effects during high moisture (fog or night rain) conditions. Wide spread lamps obviously have more issues with pilot glare than narrow beams. The small fence-type shields you see on the wingtips of a Cessna Citation II through V, just inboard of the recognition lamps, are designed to prevent halation. Increasing the beam intensity by using an HID in place of the stock halogen lamp required a narrow beam spread to avoid increasing the fence by 2 inches in height and 3 inches in length. Increasing the fence size would have brought the wingtip design back into the ACO for engineering review and delayed the STC by 2 years.

All propriety nonsese to get a PMA. The regulations do not define any of that. Many aircraft have the same part # bulb for landing and taxi lights. Others only have one bulb.


All the more reason to skip the PMA/STC process and sell/market aftermarket parts as not FAA approved but field approval only. I know a guy who has sold thousands replacement battery boxes for cessna that way.

Or just go EAB