• Wing Span: 38 in (97 cm)
• Wing Area: 585 sq in (3774 cm²)
• Length: 34 in (86 cm)
• Weight: 2.9 lbs (1.3 kg)
• Engine: .15 - .40 2 - cycle
  (2.5 cc - 6.5 cc 2 - cycle)
• 3 Servos required

A discussion was going on over early morning coffee among some club members as to an R/C project that could taken on as individuals but with a common theme. The criteria decided was that the project be reasonably inexpensive, easy to build, fairly uncommon, but most importantly it had to have a huge "WOW" factor. It did not take too long to unanimously decide on the Diamond Dust. Each has since built a Diamond Dust and they have become the terror of the skies.

The box that contained the Diamond Dust was small as there were not a lot of parts. All wood parts, plywood and balsa sheet, were laser cut and very accurate. All ribs and the engine mount were plywood. But particularly noteworthy were the two spars and leading edges, which are made of fiberglass and carbon fiber rods making them incredibly strong. All hardware needed to complete the project was included and of good quality. Only a piece of 3/8" triangle stock was added to provide a beveled leading edge on the elevons and two soldered connectors for the elevon pushrods.

Construction was quite simple. The ribs, trailing edge and spars were assembled and held together with rubber bands on top of the plans. Once everything was aligned, all joints were glued. The ends of the spars and leading edges were wrapped with Kevlar thread and flooded with thin CA. This makes an extremely strong airframe. The leading edge fiberglass rods were painted with Balsarite so the covering would stick better and it worked just fine. Before covering, a little thought about support for a tuned pipe makes life simple. One builder used a simple piece of coat hangar wire glued to a plywood rib and bent into the shape of an upside down "L". With this plane, simpler is better.

Covering was not hard either, but color choice is critical. Top and bottom must be clearly contrasting and bright. This particular model is covered with Safety Orange Ultracote with black stripes on top and white with black on bottom. The gap between the trailing edge of the plane and leading edge of the elevon was covered to prevent any elevon flutter. A mistake was made in making a design of Ultracote on top of Ultracote on the bottom with the leading edge of the design running straight from wingtip to wingtip. On the third or fourth flight, the speed was so great that the wind ripped off the design in one instantaneous "bang".

A Thunder Tiger Pro .36 was installed with an APC 9X7 prop and a MACS tuned pipe and header. This combination gives about 16,100 RPMs. A micro servo was used for the throttle and a 270 mah battery to save weight. Unlike the others of this group, the fins were mounted perpendicular. The others were mounted at an angle using the included angle gauge. A JR 8103 is used to control the plane with 85% exponential rate on the elevator and aileron function. It might be possible to fly this plane with dual rates but it has not been tried. Exponential controls are a necessity.

Although building this plane was fun and easy, flying is where the Diamond Dust really shines. After the plane is trimmed out on the first flight, the plane could easily be hand launched without the need for an assistant by holding the left wingtip and setting the right wingtip on the ground. While running the engine up to about 1/2 - 3/4 throttle, the plane will just pull away. It is simple and looks really cool.

Once airborne, the need for highly visible colors becomes apparent. This plane goes a long way in a short period of time. It is surprising to find out that the plane is extremely easy to fly. At slow speeds, it is docile and friendly but when the throttle is advanced, this beast comes to life! The airframe seems almost indestructable. In a full throttle vertical dive with speeds estimated at about 120 mph, the elevator can be pulled fully back and the plane will do the bottom corner of a square loop before the blink of an eye with no fear of the wing collapsing. Extremely fast turns are easy once a feel for the plane is gained. As long as the plane is rolled no more than 90°, a hard pull on the elevator results in the plane changing directions almost instantly. There is no apprehension with the Diamond Dust although one member of the group lost orientation a couple of times.

After some minor calculations, the maximum speed has been determined by the following formula:

Two (2) people were placed 500 feet apart. One would start a timer as the plane flew past and then he would stop the timer as the other person signaled the plane had passed him. Then, the following formula was used to calculate speed:

Although the engine unloaded some in flight and probably turned more than 16,100 RPMs, the fact that measured speed was less than 3% below calculated max speed indicates that the plane has very little drag. It is fast! These planes are more than just fast and maneuverable, they are great fun to watch. With four (4) of them in the air, this is an instant circus! The goal is six (6) or more in the air at one time.

The objectives have been met. This project was not very expensive, not very common, a snap to build and the "WOW" factor has shot through the roof! What will these four (4) active imaginations dream up next!