On Aug 27, 8:46 am, "RST Engineering" wrote:
You are correct, of course, but let's do the math. Let's figure a 3000'
long strip with runway and taxiway lights every 200' along the edge. That's
15 lights times 4 (two runway, two taxiway) or 60 lights. Throw in another
20 lights for end lights and other miscellaneous lights for a total of 80
lights times 100 watts a bulb. That's 8000 watts or 8 kw. Fifteen minutes
is a quarter of an hour, so you burn 8/4 or 2kwh in that period of time.
Even in the prime daytime a kwh goes for about 15 cents, so you have
"wasted" 30 cents.

I give you that waste is waste, but 30 cents isn't a king's ransom either.

Our ARCAL system uses 10-watt bulbs. I don't think too many
systems would need 100-watt bulbs. We don't need to light the entire
pavement. Ten watts is bright, and I use the lowest setting for
landing so that the glare on the plexiglass (all those tiny scratches)
doesn't make my pupils close up and lose sight of the surface.
But even at 10 watts it adds up. In this area there are a lot of
small airports on the same 123.2 MHz, and if a pilot activates the
lights at one, the lights at a dozen others go on as well. And every
time there's a burst of short transmissions, three keyings within 5
seconds, they reset so that they can be on for hours at a time until
everyone gets tired and goes home to bed.

Dan