At the November, 2006 JR INDOOR RC FESTIVAL Terry Nitsch, the Event Director, set up a water tank approximately 60 X 15 feet and several inches deep. From this tank, many micro size RC electric aircraft were able to take-off from and land on the water. But with a new twist --- the flying was indoors. One of the little airplanes that caught my eye was a tiny, Almost Ready-to-Fly (ARF) RC electric that is now being offered by BP Hobbies (http://www.bphobbies.com/). The airplane is called the Sand Bird and has a 21-inch wingspan, with 89 square inches of wing area and a total weight of 5 to 7 ounces depending on the equipment used. The Sand Bird requires full, four-channel control of ailerons, elevator, rudder and the electric motor’s throttle.

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The list price of this built from balsa and factory covered ARF model, including the electric motor, is just $59.95. The Sand Bird has a typical flying boat configuration, with the motor mounted up on a pylon above the wing and two tip floats for stability when taxiing on the water. This is what it looks like floating in the water.

All of the Sand Bird’s flying surfaces come pre-covered with an iron-on material that resembles BP Hobbies SO-LITE (actually Solarfilm, a low-temperature heat-shrink covering). These kits are available in light green (as was mine), orange and purple. The control surfaces (aileron, elevator and rudder) come pre-hinged but I’ll say more about that in a moment. The fuselage is basically one big float with a step to help the airplane get off the water. It is covered with an opaque iron-on covering.

Despite the excellent construction and covering job, I did find that the fuselage takes on some water. To correct this situation, I ironed on a second layer of covering on the bottom of the fuselage, right over the first layer. I used BP Hobbies clear SO-LITE which is a transparent material. That seemed to “plug” any holes and proved a fast fix.

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The motor supplied with the Sand Bird kit is a 12 mm diameter, brushed variety. I was advised by the folks at BP Hobbies that, if I intended to fly off water, I should consider a stronger motor. I’ll talk more about the substitute motor in a while.

The two wing tip floats are made from balsa and are thoughtfully factory painted with a clear coat of some form of urethane to make them waterproof. They install easily into slots cut in the bottom of both wing panel. The wing, by the way, comes already assembled (one piece, right out of the box).

The airplane comes with a fairly complete hardware package. But my kit did not come with a wing mounting screw (Ed. Note: I don’t know Bob, but that brass-colored bolt looks suspiciously like a wing mount bolt to me.). I assumed it was a 2-56 thread but found out that it was likely a metric thread. So I quickly passed a 2-56 tap through the supplied “T” nut and used a 2-56 X ½-inch Allen head screw to hold the wing in place.

At the front of the radio compartment (by the wing’s leading edge) is a small notch that accepts the wing hold down peg. I found it necessary to “open up” this slot so that the peg would fit more easily. You best try this fit right at the beginning of your assembly job. Make sure it is tight with no “play” either vertically or horizontally. If you accidentally sand it too large, use 1/64- inch ply shims to tighten the fit.

Photo 10 shows the wing hold down peg just referenced. It is located on the bottom of the wing and projects forward just enough to fit into the slot noted in the previous photograph. This plywood peg was not secured with much cement, so make sure to add a coat of your own 5-minute epoxy. If that peg breaks off, good-bye wing!

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As mentioned earlier, the control surface hinges were quite stiff. I wasn’t sure if it was the hinge material or the fact that too much cement was used. But if I had left the hinges as is on the ailerons, the little servos might have stalled from the extra load. To correct this situation quickly and easily I just cut off the ailerons and then reinstalled them using SR Batteries Gapless Hinge Tape (http://www.srbatteries.com/). I did only the ailerons at first, but later found that my rudder was having a tough time moving and so I redid those hinges also with the SR tape.

I first spotted the stabilizer in position with some thin CA cement. Then the vertical fin came next. I followed that with an application of 5-minute epoxy cement. Make sure the stabilizer is parallel to the wing and that the vertical fin is 90-degrees to the stabilizer.

I used DuBro (http://www.dubro.com/) micro control horns on both the rudder and elevator along with DuBro mini EZ connectors that allow me to adjust both control surfaces.