Upgraded landing lights for CubCrafters Carbon Cub FX-3

[ve6yeq]

I placed an order last week for 2 XeVision XeTREME LED landing lights (custom programmed to power up in strobe mode) that should be here in the next couple of weeks. I decided on dual landing lights because the current wing mounts are pretty narrow, so I don't think a wider "taxi" would work very well there, not to mention that taxi lights really need to be mounted as low as possible. I will be looking for a different taxi light solution if I start flying at night (maybe just reuse the WAT Parmetheus™ G3 Par 36 Taxi Light that is currently in the right wing with a landing gear mount).

I am in the process of selecting a 14 Vdc to 28 Vdc setup power supply to mount under the panel so I can use the existing 20 AWG wiring in the wings. There are cheap Chinese ones online and a few better-looking US-built ones built for marine use, which I am leaning towards.

 

[Cactus Charlie]

not to mention that taxi lights really need to be mounted as low as possible.

Why do you think that? I would have expected best ground illumination with the light source as high as practical.

The sun does quite well at Noon.

 

[Cactus Charlie]

Also, high mounted taxi lights which are pointed down will give good ground illumination without dazzling other pilots.

 

[Meconiates]

I placed an order last week for 2 XeVision XeTREME LED landing lights (custom programmed to power up in strobe mode) that should be here in the next couple of weeks. I decided on dual landing lights because the current wing mounts are pretty narrow, so I don't think a wider "taxi" would work very well there, not to mention that taxi lights really need to be mounted as low as possible. I will be looking for a different taxi light solution if I start flying at night (maybe just reuse the WAT Parmetheus™ G3 Par 36 Taxi Light that is currently in the right wing with a landing gear mount).

I am in the process of selecting a 14 Vdc to 28 Vdc setup power supply to mount under the panel so I can use the existing 20 AWG wiring in the wings. There are cheap Chinese ones online and a few better-looking US-built ones built for marine use, which I am leaning towards.

Nice. I look forward to reading about your review. For my FX3 build, should I have them run 16 or 14 AWG wires for landing / taxi lights? And I assume 10amp breaker is the correct size (assuming independent circuits) ?

 

[ve6yeq]

Nice. I look forward to reading about your review. For my FX3 build, should I have them run 16 AWG or 14 AWG wires for the landing /taxi lights? And I assume 10amp breaker is the correct size (assuming independent circuits) ?

I would run 16 AWG to each wing. In a perfect world, you would use 2 x 10-Amp breakers to protect each wing independently or a single 20-Amp breaker for both. Remember that 2 100W lights are like 17A at 12Vdc, and that, given the 40A alternator, there is not much power budget left for future lights that draw more power without replacing the alternator.

 

[Neal]

And that was my thought...at some point with EarthX, upgraded landing lights, IFR panel, where are you in taxing the alternator to the point where maybe a 60A (or whatever the next level is) should be opted?

One of my favorite parts of Draco when I watched it at OSH 2018 was the 737 landing light.

 

[ve6yeq]

And that was my thought...at some point with EarthX, upgraded landing lights, IFR panel, where are you in taxing the alternator to the point where maybe a 60A (or whatever the next level is) should be opted?

Then there is the issue that the alternator will only deliver the rated power when the RPMs are above idle (I normally do "power off" 3-point landings). So, for the 40A alternator on the EX-3, it appears we only see about 30A during warmup at 1000 RPM (e.g., ~22A charging the battery and ~8A for avionics).

One of my favorite parts of Draco when I watched it at OSH 2018 was the 737 landing light.

From the build videos, the wingtip landing lights appear to be AeroLED Sunspot 64 lights drawing about 200W each. The datasheet shows 420k candela peak and over time decreasing as the light heats up by at least ⅓ (~275k?). The XeVision XeTREME LED landing lights drawing 100W are spec'ed to about 322k and decreasing slightly from there to around 310k. So, from a datasheet perspective, the lights should be in the same ballpark as those on Draco.

It would appear that the current 737 lights from WAT have a peak brightness of 1.19m candela while drawing 200W, and assuming the same brightness decrease over time as the smaller ones, should be around 600k candela after warm-up. So definitely brighter than the previous-generation Sunspot 64s.

 

[ve6yeq]

Why do you think that? I would have expected best ground illumination with the light source as high as practical.

The concept of mounting headlights low is from my background in bikes and cars, where low mounting reduces unwanted illumination from rain, etc., and provides the best depth perception. There appear to be limited published studies that I can find - only one from the US DOT that suggests that lower mounting is better, especially for newer (then HID) lights.

For aircraft, there appears to be an SAE Aerospace specification for "LED Landing, Taxiing, Runway Turnoff, and Recognition Lights" [SAE-ARP-6402]. Like all specifications, this one is not freely available, but with some Google Foo and thanks to a copy being included in someone's intern report appendices, it can be found . There are some measurements of heights above ground for the wing leading edge and landing gear to be able to repeat the calculations for the Cub in both wheel and 3-point landings - I will throw in a tape measure into my flight bag for my next visit to the airport.

 

[Neal]

The thing that intrigued me the most with the 737 landing light was anti-collision. Being seen is priority 1 and that light answered that bill.