Ch 22 - Electrical/Avionics - Part 18

Interior lighting

Flying at night is exciting, and presents different sets of challenges. I prefer “boring” day flying, but one has to be prepared in case things run long, and arriving late cannot be avoided.

JT’s current level of indoor lighting consists of a dimmer circuit connected to the fuel gauge, engine instruments, compass, and two tiny spotlights on the left and right sidewalls that are aimed at the panel. There are no other lights illuminating the rest of the cockpit which is left in complete darkness at night.

Red knob is the existing dimmer

I decided to change all of this by installing down pointing Led lights under the longerons. I will start up front, and eventually do the passenger’s compartment as well.

The lights I chose to install came from pilotlights.net and have red and white alternating Leds that can be controlled independently. 

2-color high output LED light strip

Each strip is one yard long (1m), and has adhesive backing. Two are required for each seat, so the total cost soars to around $200, plus additional wiring, switches and PWM controllers.

Luckily JT’s dimmer is a PWM controller, and it just so happens that it has one last "channel" available that can be used to control the Led strips I’m planning to install.

Yellow wire is the open PWM "channel"

The d-sub used with the PWM controller was the soldered kind and was in pretty rough shape after 15 years, so I  replaced it with a crimp-on d-sub type.

Wires were literally breaking off the old soldered-type d-sub 

Figuring out where to run the wires

One has to become comfortable soldering in any number of locations

One at a time all wires were replaced, and the old d-sub was history.

"Thank you for your service!"

The new interior lighting makes it possible to perform any number of tasks, such as reading the checklist at night, or writing clearances on a kneeboard, just as easily as one could do during the day.

Red lights to preserve night vision

White light to really see what's going on

The white lights could be appropriate during preflight and post-flight duties, whereas the red lights can illuminate the cockpit while preserving night vision in flight. 

I added black heat shrink over the canopy lock mechanism to reduce the reflection of the lights on the bare aluminum rod.

Slipping black heat shrink tube over the canopy lock tube

Light reflecting off of the canopy locking rod was greatly reduced by using heat shrink

I used a three way switch White/Off/Red in conjunction with the  existing cockpit dimmer.

One three way switch and a dimmer is all it's needed

Led lights and dimming in action

Another suitable PWM dimmer is the KR6 from www.kicklighting.com. I will be installing that in the passenger's compartment.

PWM dimmers

Here’s the schematic of my generic installation…

I think this is an easy upgrade that can dramatically impact safety of flight at night.