| Almost or many RC airplane enthusiast dream of | | | | Scale Effect". You can't scale down the air molecules |
| having their favorite full size replica to bore holes in | | | | & the viscosity of air. The behavior will be different. |
| the sky. But it will not be easy just to copy the | | | | The wing location & wing area, horizontal and vertical |
| exact dimension of the full size airplane and then | | | | stabilizer area & location, airfoil design, plays a major |
| scale it down to what ever you desire, like for | | | | role on its stability. |
| example 1/8 scale, ¼ scale so forth and so on. | | | | Redesigning the airplane is essential. The model has to |
| Even though you know how to use CAD software | | | | be redesigned based on the lift and drag coefficients |
| to design and draw the airplane, without considering | | | | and Reynolds number on its miniature dimensions to |
| the aerodynamic principles, you won't have a stable | | | | achieve stability. This is why some Almost Ready to |
| airplane. So this is the first step on how to fly scale | | | | Fly, Ready to Fly or Kits have 30% or 40% scale |
| model airplanes. It will be impossible to fly your scale | | | | specification. Meaning only 30% was copied from the |
| model airplane without considering the aerodynamic | | | | full size airplane. Possibly the horizontal stabilizer area |
| design. Again, before you attempt to build & fly your | | | | was modified or vertical stabilizer. Changed the airfoil |
| very first scale model, you should have already build | | | | type or wing area. In order to achieve stability. The |
| your skill to at least an intermediate level. Meaning, | | | | closer its size to the full size airplane, the more you |
| flying a non-scale shoulder wing design type of model | | | | can copy the exact dimension and behavior. This is |
| airplane. Then choose the trainer type full-scale model | | | | why ¼ scale model airplanes are popular to |
| airplane like the Cessna 150 or J3 Piper Cub. | | | | those really serious on RC airplane modeling. |
| At least those airplanes have a built-in stability design. | | | | Considering the cost and set-up, danger to life and |
| The wings constant chord and rectangular (for J3 | | | | property, it will only be possible for those who were |
| Piper Cub). High wing location, meaning the wings is | | | | well to do. Imagine how many gallons of fuel it will |
| above the fuselage, which have pendulum stability. | | | | consume! You will also need bigger flying field. Good |
| Landing gear is tricycle type (for Cessna 150). But | | | | thing that gas or petroleum engines (chainsaw |
| wait, does this mean the stability is the same when | | | | engines) are fit to use in those monsters which |
| you scale down those airplanes? The answer is No. | | | | reduces the cost of fuel. Unlike using methanol, |
| Those airplanes will fly terrible when you scale it | | | | castor oil and nitromethane for fuel on glow engines. |
| down and copy the exact dimensions. Like what I've | | | | So before having any expectations on acquiring one, |
| mentioned previously, the aerodynamic design should | | | | first consider those facts. |
| be considered. This phenomenon is known as " The | | | | |