There are a lot of ways to construct a remote controlled airplane. Different kits are available for designing a RC plane. Cost and performance of RC plane is depend on the way of construction. Normally kits are made of foam or plastic or balsa wood. For the construction of fuselage formers and longerons are used. For wings and tail surfaces normally spars and ribs are used. Solid sheets of wood also sometimes used for structure construction. For heavy RC airplane construction a composite wing consisting of expanded polystyrene core covered by the safety veneer of wood is used. If we want to make remote controlled airplane for windless environment, the lightest models are most preferable.
For lighter RC airplane construction frames are made of balsa wood and carbon fiber with thin plastic films(just like rainbow colored oil films). The main advantage of using EPP (Expanded Polypropylene) foam planes is that they are elastic in nature and normally sustain very short or remain unchanged during the event of an accident. This material also has different names such as Aerocell or Elapor (mainly depend on the company that made).
In the late 1980 an United States company name US Air Core used twin wall polypropylene material for the construction of remote controlled airplane. They also have used double skinned Correx (converting it into flat sheet form). This model is quite weighty ( up to 2 kg) than the normal model because of using material thickness as 5 mm, but has the above average flying speeds. Mugi (small delta glider) was invented when this material was used which results in developing the high performance of Mugi Evo. The main advantage of construction of RC planes is that any grade of thickness can be used by proper scaling. Nowadays corrugated plastic or Coroplast material is used by the amateur hobbyists for the construction of RC planes. They have successfully able to invent a variety of new model design for the RC air crafts. These models are commonly known as SPADS ( Simple Plastic Airplane Design).
When designing a flying model it should be kept in mind that it should be designed in similar with the basic principle of full sized air crafts, but their construction can be varied from most static models. Sometimes remote controlled airplanes are made by borrowing construction techniques from the full size air craft, but they rarely use metal in structures construction.
RTF (Ready To Fly) planes are those pre-assembled kits that require only wing attachment or other basic things. These type of RC planes can fly only for a few minutes. On the other hand ARTF (Almost Ready To Fly) planes are those having more assemble and often basic construction. These type of RC planes can fly from 20 to 50 plus hours (depending on detailed constructions). Normally kits are used to separate purchase and installation of servos, type of motors used, speed controller and often control rods. This is also an advantage of RTF over ARTF airplanes.