I figure that since I am quite new to aviation I must be coming off as kind
of dim-witted. I'm rebuilding this KR-2. It is an experimental. So I am
experimenting. And trying to do something large cool on small money. And
not small in aviation speak but small in po'folk speak.
I've spoken to folks at the local FBO, EAA, posted to a couple of news
groups, surfed the web and contacted 'experts' direct. I keep getting
responses that say what I can't do or what I ought to do or all of the
complexities involved that should just leave me terrified to do anything.
So far no straight answers. So at the risk of seeming impetuous I'm going
to try again except this time request no one respond who does not have a
direct answer to the query. And maybe this time I can do a little better at
presenting my questions related to just only specifically merely one problem
at a time.

First problem; Navigation lights. My plane has none at this time. I want
to imbed them into the wing tips before I start to repair the damage I am
inflicting with my belt sander and grinder. Strobe lights too. The tail
light was wired into the rudder but never installed. I want to put LED
illumination for all points of light. If the damn plane never flies I don't
care. I'm experimenting and want to create an inexpensive clean legal LED
navigation and strobe lighting system for now so I'll try to stick to just
that point.

1. I've downloaded copies of FAR 23.1367 through 23.1401 from the AOPA
web site.

2. The angles of view referred to in parts 23.1391 through 23.1395 do not
make clear sense to me.
Does anyone know if the LEDs referred to as follows will work and stay
within legal specs?

3. In the Mouser catalog there is the Kingbright red LED part no.
L934SRCD rated at luminous intensity of 500 to 700 at an angle of 50
degrees.
How does this compare to the FAR 23.1391 minimum intensity of 40
candles?
Is the 50 degrees referred to in the Mouser catalog to be considered
conical?
Will overlapping these LED beams cause a violation of 23.1395 somehow?

Please understand that I am not trying to be rude... or dangerous. But the
spirit of this is to find out who knows what I CAN do.

Thanks.
Forrest

On Sat, 03 Jan 2004 19:22:29 GMT, "Forrest" > wrote:

:I figure that since I am quite new to aviation I must be coming off as kind
:of dim-witted. I'm rebuilding this KR-2. It is an experimental. So I am
:experimenting. And trying to do something large cool on small money. And
:not small in aviation speak but small in po'folk speak.
: I've spoken to folks at the local FBO, EAA, posted to a couple of news
:groups, surfed the web and contacted 'experts' direct. I keep getting
:responses that say what I can't do or what I ought to do or all of the
:complexities involved that should just leave me terrified to do anything.
:So far no straight answers. So at the risk of seeming impetuous I'm going
:to try again except this time request no one respond who does not have a
:direct answer to the query. And maybe this time I can do a little better at
:presenting my questions related to just only specifically merely one problem
:at a time.
:
:First problem; Navigation lights. My plane has none at this time. I want
:to imbed them into the wing tips before I start to repair the damage I am
:inflicting with my belt sander and grinder. Strobe lights too. The tail
:light was wired into the rudder but never installed. I want to put LED
:illumination for all points of light. If the damn plane never flies I don't
:care. I'm experimenting and want to create an inexpensive clean legal LED
:navigation and strobe lighting system for now so I'll try to stick to just
:that point.
:
:1. I've downloaded copies of FAR 23.1367 through 23.1401 from the AOPA
:web site.
:
:2. The angles of view referred to in parts 23.1391 through 23.1395 do not
:make clear sense to me.
: Does anyone know if the LEDs referred to as follows will work and stay
:within legal specs?
:
:3. In the Mouser catalog there is the Kingbright red LED part no.
:L934SRCD rated at luminous intensity of 500 to 700 at an angle of 50
:degrees.
: How does this compare to the FAR 23.1391 minimum intensity of 40
:candles?
: Is the 50 degrees referred to in the Mouser catalog to be considered
:conical?
: Will overlapping these LED beams cause a violation of 23.1395 somehow?
:
:Please understand that I am not trying to be rude... or dangerous. But the
:spirit of this is to find out who knows what I CAN do.

Here's a good place to start

http://www.periheliondesign.com/redandgreenledpositionlights.pdf

I looked at the LED nav light problem myself after a guy posted his
lights for sale here. Neat stuff those LEDs and a good fit for many
lighting applications. Now to answer your questions:

> 3. In the Mouser catalog there is the Kingbright red LED part no.
> L934SRCD rated at luminous intensity of 500 to 700 at an angle of 50
> degrees.
> How does this compare to the FAR 23.1391 minimum intensity of 40
> candles?

At the peak (centerline), you'd need 80 (40/.5) LEDs to produce the
required intensity, but off center, you'd violate. The viewing angle
specs on LEDs often give anglr at which the intensity drops 50%. The
good news is that there has been a sort of breakthough in LED
efficiency in recent years, with outputs in the multi candle range,
not sure if you're going to get these from Mouser though. They are
more expensive, roughly proportional to their light output. So we're
talking a couple bucks each maybe.

> Is the 50 degrees referred to in the Mouser catalog to be considered
> conical?

Yes, although there are LEDs available that have different patterns in
azmuth and elevation.

As for powering your array, I wouldn't worry about a constant current
supply like the one guy did. Just stack them in series and put a
dropping resistor in series with each leg. Incandescent nav lights
fluctuate in intensity with the supply voltage and these will change
less then those.

> Will overlapping these LED beams cause a violation of 23.1395 somehow?

IMHO, no. Just meet the min. intensity in the prescribed directions.

Regards