Led position lights

I just ordered some high intensity red/green leds from http://www.oznium.com/prewired-superflux that seem to be packaged already suitable for mounting under the wing tip lens. The will fit into a 3/8" hole. I plan to secure them from the backside with epoxy glue. Price for two including shipping was under $12. Worth a try anyway.

Bevan
RV7A wiring
 
There has been a lot of LED (high current) sources mentioned in this thread: http://www.vansairforce.com/community/showthread.php?t=14888 Which most deliver those high current LEDs you wish to find from superbrightleds.com.

And the site you mention, the most of their LEDs are just normal LEDs, not anything special we look for. Those mentioned to be 1 Watt or so might be something, but likely they will be beaten by many other. Like those have worse viewing angle than many other high current LEDs which leads easily to higher intensity so don't get fooled...

For good reference you should look for www.lumileds.com (look for K2 and Rebel -types) -- they put good reference line in terms of intensity, size, temperature handling, price etc... so if you find something better, please let us know!

PS. As you may guess, there are lot of different kind of manufacturers in China. Some of them you may contact them directly and save some bucks and the list is 'end-less' http://www.made-in-china.com/ There you may find something less good with less money. Not necessarily bad option.
 
Do the research

If you are going to build your own LED Nav lights, then let's at least attempt to be legal. Best place to start is the Whelen website, which shows the emission patterns and intensities:

http://www.whelen.com/pb/Aviation/2007_Aviation_Catalog.pdf

Actually, you need to Reference FAR 23.1389-1391 for the exact values, but the Whelen catalog has a good diagram. FAR 23:

http://ecfr.gpoaccess.gov/cgi/t/tex...e&tpl=/ecfrbrowse/Title14/14cfr23_main_02.tpl

Next, you need to be able to either calculate or measure the correct patterns. You can just bundle a bunch of LEDs together and say "looks pretty bright to me", but unless you can measure the emissions from different angles, it is hard to be sure if you are meeting the specs. You can find relatively cheap light intensity meters on EBAY. Just be sure that the meter will measure what you want, or you can convert the meter's measurements into intensities that match the FAA specs (candellas).

Here's a few links for light intensity measurements:

http://www.electro-optical.com/whitepapers/candela.htm

http://en.wikipedia.org/wiki/Luminous_intensity


If you try to calculate the patterns and intensities based upon the LED specs, then you can get into trouble. Some LEDs do not live up to their specified output intensities. Also, it is a little hard to be sure that the pattern really covers the advertised angles without actually measuring the outputs.

Now-a-days 10,000 MCD LEDs are very common and cheap, so they are likely to meet or exceed the specs. However, when I ordered 130,000 MCD LEDs, they actually measured closer to 65,000 MCD. So, beware. BTW: I would not recommend SuperBrite LEDs, their products are 5-10 times as expensive as other sources.

Luxeons have high intensities and wide patterns, but it is a little confusing to convert the lumen spec to candellas. You really should measure the pattern and intensities.

A few other links:
http://www.sportflyingshop.com/Safety/LED_Position_Lights/LEDtechnical/ledtechnical.html

http://www.jbwilco.com/Cozyweb/navstrobe.htm

Good luck,
Tracy.
 
Luxeon K2s are hard to beat these days ... bright, long life, widely available optics, well understood characteristics, and relatively cheap. There has been much analysis on VAF, and 2-3 Lux I @ 350mA per side should work for your nav lights, so 2-3 Lux III or K2 at 1000mA will provide plenty of light and coverage.

TODR
 
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