Wednesday, January 16, 2013

Lighting, Pulse Is OK - But Wig Wag Is Better!

Having an electronics background, it was bugging me not having a schematic drawing to use as reference once the electrical connector wiring  begins … especially since there will be some small changes to the electrical system. It is nice to see the "big picture" sometimes.  Van’s has a schematic drawing online for the builder to download which is drawn in such a fashion, in order to read any of the labeling, it requires zooming so far you lose all prospective. Trying to trace a wire is … well “fun”. Not!

Decided to have the entire schematic drawing printed out on 4 x 3 foot paper and it was still tough to read the labeling, so had the drawing divided into four quadrants and each of those printed onto 4 x 3 foot sheets. Honestly, the schematic would need to be about the size of the side of a cargo van as to be easily read.
                The whole schematic is now on one 4x3 foot sheet … still difficult to read the labeling but it is legible.
The lower quadrant of the above schematic printed on a 4x3 foot sheet … at least now it’s easier to read the labeling.

Lighting - pulse is OK, but wig wag is better!
Although not much is being accomplished in the shop, behind the scenes there has been a flurry of activity. The decision was made to order a second landing light so wig wag lighting would be possible. One thing is clear to me, a plane flying in the pattern with wig wag wing lighting simply commands attention!

Those familiar with the RV-12 lighting kit know, as shipped from Van’s, the lighting kit only has one landing light which is installed in the right wing. Basically, the reason for this is not to over tax the somewhat anemic electrical system of the Rotax engine. The landing light, which is manufactured by AeroLEDs, has the provisions for both steady light and a pulse mode which Van's incorporates. The current draw is 2.6 amps when the landing light is on. In a two light instillation, the pulse mode can become a wig wag mode. For wig wag operation, one light becomes a master and a wire is run from that light's master output to the slave input on the second light which enables wig wag operation. That got me thinking, if one were to add a second light on the left wing but only use the wig wag mode, the total current should still be 2.6 amps … because only one light is illuminated at a time.   A call to AeroLEDs technical support confirmed my suspicions, so an additional light and mounting hardware was ordered from Van’s Aircraft on Monday.

I still plan on running a power lead to the left landing light’s steady on, but will not connect it to the switch on the panel. But it will be there should there be an improvement in the electrical system in the future which allows for more power. To be honest, I’m not planning on flying at night anyway, so doubt the landing light will ever be used as such. But using the wig wag mode of those bright lights … you bet! See and be seen!.

The decision to add an additional light on the left wing created yet another grommet issue … the 437-4 grommets I just ordered proved to be a little tight with the addition of the second shielded cable for the landing light along with the Tygon tubing, so an order was placed through Mouser for 437-5 grommets. These grommets use the same size .437” mounting hole as the 437-4 grommet but have a wire hole of .312” as opposed to .270”. The new grommets just got here today so will see how well they work out tomorrow … suspect there will be plenty of room now and the good news is the new grommets still only require the hole in the ribs being enlarged to the next size up on the step drill from the original hole size.