In , Robert L Bass wrote:
salty wrote:

... The simple answer is that most LED replacements
for incandesent bulbs in almost ANY application other
than indicator lights on a panel, are accomplished by
use of arrays of LED's, not a single LED.

Therein lies the problem. Lamp housings using reflectors or prismatic
lenses for nav lights and other purposes are designed to use a light
coming from a single point. Incandescent bulbs do that rather well. An
LED array can't work as well in that type of lamp because only a few of
the LEDs are at the focal point. Light emitted from the rest of the LEDs
will be scattered in wrong directions.

That does not mean that LEDs can't serve well in nav lights -- only that
they don't work well as replacements for standard bulbs in *existing*
lamps.

There are nav lights out there sufficiently simple and non-critical
in design such that someone can make an LED retrofit for the bulb that
gets the light to meet the spec - despite the difference in emitting
surface geometry and directional characteristics.

Motor vehicle lights are not as easy to make LED incandescent-retrofit
bulbs for with achievment of legal requirements being maintained.

- Don Klipstein )