PC fan to make lights ???

[Paul Taylor]

I remember reading a long time ago about someone using a little cooling fan on there plane to make it run some lights on there plane for night flying. Anyone have any info?

[Bob Reeves]

Never actually done it but should work fine.. The older P1 processors had smaller cooling fans than the current crop. If you don't have a fan any PC shop should be able to fix you up for almost nothing..

Radio Shack should have LED's you could use and also will have the resistors.. You will need to measure the voltage the fan puts out.. Drive down the road with the fan out the window at 50-60 MPH with something like a 10K resistor across the fan output and see what the voltage is..

See if the fan has a current spec, not exact but will give you an idea of what current it might be capable of supplying. With that info and the current spec on the LED's you should be able to calculate the needed dropping resistors. Look up OHM's law and have fun...

[Wynn Robins]

Gary Weaver was the mind behind this - search on SSW for it

[sleepy gomez]

For the little fans, LEDs and other stuff see the Marlin P. Jones catalog and get on their mailing list.  Tons of stuff.  For online: www.mpja.com  SLEEPY

[John Stiles]

We always used "grain of wheat" bulbs and a small battery pack.....I would sure like to see the set-up you are speaking of!

[Steve Helmick]

With LED lights, I think you'd be far (FAR) better off using some sort of small battery pack, and skip the weight and drag of the fan/generator plot.  Steve

[Richard Grogan]

Like Bob sez. If you can find a trashed out laptop, the uPC fan would be the smallest with maybe(just maybe) enough umphh. But like Randy said, the battery route would be better weight wise. You'd have to figure a place to mount it(fan) in the airflow, would be a challenge in itself, and try not looking too goofy. LEDs are available with very low current drain, and with resistors in place, a very small battery(lipo or nicd) (like we use for micro helis and planes from the dark side, about the size of a stick of Dentine gum))could be concealed most anywhere and you could add a small charging jack for it.I think you could also add a timer/flasher chip to it and make them blink sequencially.If thats what you want to do.

[A side note for you photog types out here... A plane decked out with (LED)lights could be a great subject to use for some very interesting photography. I know many of you have seen carnivial Ferris Wheels and such photographed at night, at long shutter speeds.Gives a really neat light show! This is accomplished by setting the camera on a tripod(very still!) and setting the shutter speed for a lengthy time (say, 2-10second).The same thing could be accomplished shooting a PA plane doing a part of the pattern. Just something to think about...

if you fly well enough to fly at night! ]

[minnesotamodeler]

That very thing was done many years ago and published in one of the mags, probably 1960s.  They used a penlight taped and faired into the LE--article was "how round is a loop" or something like that, one of the exposures showed a virtually perfect circle, checked with a compass (shot from inside the circle, penlight on the inboard).  I remember being VERY impressed by it.

[Alan Hahn]

Here's another idea along this line. First replace the glow engine on the front with an electric motor. Then also add a motor on the tail.

Now when you fly using the one on the front for propulsion, the one on the back will work like a generator and supply power to the front--no battery needed!
 

[Scott Hartford]

LEDs usually work best with a forward voltage of 3v. A watch-type battery (3v) will run an efficient LED for a long time. 1 LED and 1 battery, no resistor. Very light.

[Dennis Vander Kuur]

Paul,
Two years ago at the SIG contest and for the last two years at the FCM contest in Muncie, Mike Schmitt flew the stunt pattern at night with a lighted plane.  He used blue and yellow neon light tubes, powered by a 9 volt battery, to outline the wing and fuselage. He picked up the neon tubes and power converter from a vendor at the NATS helicopter area. The helicopter guys put on a big night time hot dog flight competition and use a lot of these type of lights. Check with Mike and he should be able to give you some vendor information.
DennisV

[Bob Reeves]

LEDs usually work best with a forward voltage of 3v. A watch-type battery (3v) will run an efficient LED for a long time. 1 LED and 1 battery, no resistor. Very light.

Only way that would work is if the internal resistance of the battery happened to be enough to limit the circuit current to something below the rating of the LED. Might get lucky but odds are you will end up with a hand full of blown LED's and dead batteries.

[Scott Hartford]

Small CR type batterys work fine. Most of the little keychain lights use this same setup. No resistor, works.

[John Stiles]

Only way that would work is if the internal resistance of the battery happened to be enough to limit the circuit current to something below the rating of the LED. Might get lucky but odds are you will end up with a hand full of blown LED's and dead batteries.

"resistor wire" 

[Andrew Tinsley]

Hi All,

Not too sure about this one, but I seem to remember that some of the better quality fans, had some form of inbuilt invertor, the fan was supplied with DC and the invertor generated AC, think this was to get away from brushes and improve reliability. Needless to say, one of these fans would not work in the suggested generator! Moral is if you want to do it, use a cheapie fan!
  When I was a kid at scout camp I flew my Oliver Tiger powered Black Ghost at night, using a very small torch held underneath the wing, using the wing fastening rubber bands. Worked a treat, did the old SMAE stunt schedule and that was 50 years ago!

Regards,

Andrew.

[peabody]

My local motorcycle accessory store sells lights that stick onto the helmet with double sided tape and have little fan.....the faster you go, the brighter the light...kinda kewl....