NIGHT FLIER, PART II

By

Herman Burton

Radio Controlled Model

In last month’s newsletter, I wrote an article about a new night flyer I was building In that article, I described the 40-size Sig 4-Star aircraft I was using, RAM’s flashing navigation light system plus their bright white landing lights (servo activated). I also mentioned using some red and green 3-light LED clusters from our friendly Electronics Parts Outlet (EPO) store in the Clear Lake area to help me stay oriented with the aircraft at a distance.

However, I also stated I thought it was desirable to have some lights on the tail feathers for further orientation in the dark sky. To that end, I found SUPERBRIGHTLEDS on the internet, and bought two strands of 30 LEDs in white. I attached one strand to the top of the fuselage, terminating at the top of the fin. The other strand I attached to the underside of the fuselage, centered on the plane from the rudder forward to the wing.

I thought a string of blue lights would be helpful, attached to the leading edge of the horizontal stab. I bought two strands of bright blue, again in the 30 count light string, for this endeavor. I only used about half of the strand for each leading edge, and rather than cut off and waste the remainder, I ran if alongside the fuselage The first photo shows the tail feathers, in their completed state, lighted up

The SUPERBRIGHTLEDS come prewired on a flexible strip, and can be bent around a gentle corner. They are available either “regular” or waterproof. Since I was sure I would have to clean the exhaust residue from the plane with a soapy cleanser, the decision was made to use the water proof variety. The back of the flexible LED strip is a 3M adhesive, but to make sure the lights did not come loose, I glued them lightly with medium CA glue. Finally, I also covered them with the transparent covering.

The strips of LEDs are exactly 8 mm wide, slightly wider than the horizontal stab, which is ¼” thick. ( Eight millimeters is very nearly 3/8”.) I decided, upon consultation with an aeronautical engineer, to increase the thickness of the stab to the same thickness as the light strip to minimize the turbulence flowing across the stab, thereby making the plane easier to fly. With the additional weight of the LEDs on the tail feathers, I drilled large holes in the solid balsa stab and fin, to get rid of as much weight as possible, before I glued new 1/16” sheeting to the original solid stab and fin. The next photo shows the fin and stab after removing much of the original material, and prior to sheeting with 1/16” balsa.

Next, I bought very small on-off switches and mounted those to the exterior of the fuselage. Since I did not know how much power the LED lights would consume, and since I did not want to have to change 9 volt batteries very often, I decided to energize each set of lights with its own battery. Plus, with the additional weight of the four strands of lights on the tail feathers, I was sure I would need extra weight in the nose, which was the anticipated location for all the batteries. So, one battery/switch combination was installed for the blue horizontal stabilizer lights, one for the top and bottom white longitudinal fuselage lights, one for the wing red/green lights, one for the flashing navigation lights, and one for the white landing lights.

After the decisions for the light systems were finalized, and all components purchased, the building of the plane from the kit started. The airplane parts went together easily, and the light systems were incorporated into the construction phase. After completion, the compartment under the fuel tank was the perfect place to install all five 9 volt batteries. An additional bonus for this battery location was assisting in moving the CG forward. Only 5 ounces of lead was required in the nose for the final balancing.

The plane is powered by an OS .46 AX glo engine, which should be adequate for the 7 pound airplane. I installed an 8 0z. fuel tank, DuBro on/off switch with integral charging jack, and painted the entire airplane white before covering it with transparent Light Ultracoat. White was selected to help reflect the wing lights in between the rib bays, and a transparent covering was selected for the highest visibility while flying. The transparent covering is very difficult to manage, much like installing ultra thin cellophane! I liken it to putting on “invisible” covering. You can’t see it, you don’t know where it is, and more than once I tried to put the backing material on, and threw away the covering itself!

The last photo shows the completed airplane. I brought the nearly finished plane to the August club meeting for “Show and Tell”. As can be seen from the photo, I have painted the cockpit, rudder, and wing tips black to assist with day time flying. By the time of the next club meeting, I hope to have flown at night, and will report my success (or lack thereof!). See First Flight narrative below.

The experience of flying at night is quite similar to any other time of the day.  The cardinal rule of RC flying is to never take your eyes off your plane while it is in the air, so as long as you concentrate on watching the plane intensely, there really is no problem flying.  The bright blue and white tail feather lights were very nice to have.  I doubt the plane could be flown without them.  Perhaps, but it would be difficult.

Also, all the wing lights have a bad tendency to disappear when the plane is dead away from the pilot.  But, the tail is lighted, so that was a life saver.  The landing lights are also an excellent feature, when coming in for a landing.  Knowing the wing orientation is essential to safe landings.

All in all, a new and different flying experience, and generally speaking, fun.  The heavy wing loading on this small aircraft is not to be repeated, but it flies.  And, well enough for my first Night Flyer.

Thanks for indulging me.

                                                            Herman Burton