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Halogen lamps are terrific - they produce nearly twice the candlepower

of a standard lamp of the same wattage (current) and, in my experience

(I use the GE halogen version (G4509) of the 4509 landing lamp) last

a lot longer. In fact, after going thru several standard 4509's in a

short time, I installed the halogen unit a couple years ago, and it's

still going strong. And it is used almost every time I fly for

extended periods since a lot of my flying is in and around the LA

metro area - it's mandated when transiting the VFR corridor over LAX

and it's so busy here, I just keep it on to make me easier to spot.



I did a bit of research on halogens a few years ago as part of my

job here at the Bomber Factory and they are "good things" as far as

I'm concerned.



But (and there is *always* a "but") to produce all that brightness,

a halogen operates at significantly higher temperatures than a

"standard" lamp. It isn't a defect, it's a function of what makes a

halogen lamp work - so, be careful of enclosing one too well in any

material overly sensitive to high temperatures. The lamp will like it

just fine while your epoxy turns to bubble gum. At least give your

lamp enclosure a way to get rid of the excess heat - a little air

flow to flush the cavity should work. Don't try to cool the lamp

directly though, you'll be defeating the purpose - just try to keep

the surrounding stuff from getting too hot - doesn't take much.



Last but not least, if you're using a bare halogen bulb, don't get

your greasy fingers on it at any time. According to the literature

published by halogen bulb manufacturers, you shouldn't touch the bare

glass bulb because of the temperature at which the surface of the bulb

operates. Traces of grease or body oils on the glass will screw it up,

pronto! The best way to handle the bulb during installation is with a

*clean* cotton cloth.



<If Budweiser made a halogen lamp, what would you get if you asked a

bartender for a Bud Lite?>



Dan Schaefer

N235SP