DIY Beginner RC Plane

Great tutorial.

Batteries - The Beginners' RC Planes Guide

Batteries are available in different sizes, weights, voltages and capacities C, which refer to their stored energy expressed either in amps-hour Ah or milliamps-hour mAh. For example, a battery with a capacity of 500mAh should deliver 500mA during one hour before it gets totaly discharged (flat).

Radio control sytems are usually powered by rechargeable batteries. Rechargeable battery types available on the market today are: Nickel-Cadmium (NiCads) Nickel-Metal hydride (NiMH) and Lithium-Polymer (Lipo) batteries. Even Lead-Acid batteries are also used as ground power source.

Normally the NiCads stand more "abuse" which means that they may be charged at higher rate (normally 2 - 4C) and have the ability to deliver higher current, i.e. discharge rates up to 2C continuous or 8 to 10C during 4 - 5 minutes and even up to 100C during very short time. They have some designations such as the Sanyo AE for high capacity and AR or SCR for quick charge/discharge.

A NiCad cell consists basically in a positive plate foil of nickel metal with nickel oxide/hydroxide, a negative plate foil of cadmium metal with cadmium hydroxide and an isolating porous separator film moistened with an electrolyte of potassium hydroxide (caustic potash). The two plates are sandwiched between the isolating porous separator films, rolled up and enclosed in a nickel-plated steel can. A spring-loaded vent is fitted at the positive terminal end in order to release the electrolyte and/or gasses, in case overpressure occurs due to overcharge. See picture below.

How to Choose The Right Remote Control Airplane

If you are looking for a new hobby that is more exhilarating than fishing, remote control aircraft flying is a hobby that you should look into. Flying a radio controlled plane at high altitude and doing aerobatics is fun and exciting. But first you have to get into the business of finding the right remote control airplanes that will suit you as a beginner. It seems easy and fun but like all activities flying a RC plane takes time and patience to perfect. But there are things you must know before finding the right remote control airplanes for you. RC planes for beginners are susceptible to wind and turbulence. Because of the small sizes, these are suited for small area practice flying. And also makes them vulnerable to winds that are faster than 5 miles per hour. Your orientation of directions, up and down, left or right will be tested in flying.

Glow Engines - The Beginners' RC Planes Guide

There are two main propulsion systems used by R/C models today: The internal combustion systems (glow engines) and the electric motors. Combustion engines' energy source has so far a higher energy/weight ratio than the batteries used to power the electrics. However, the combustion engines are usually more noisy and more prone to oil spillage than the electric motors.

There are two types of glow engines: The four-stroke and the two-stroke.

Two-stroke engines are the most used, mainly because they are simple made, light, easy to operate, easy to maintain, and are usually inexpensive. Two-stroke engines operate at a high RPM and therefore can be quite noisy without a good silencer.

Electric Motors - The Beginners' RC Planes Guide

Electric powered model aircraft has gained popularity, mainly because the electric motors are more quiet, clean and often easier to start and operate than the combustion motors.

They need batteries to operate and despite some developments in this area; the batteries still are somewhat heavier as energy source compared with the gas fuel.

Thus, the electric flier has to strive to build the model as light as possible in order to obtain a reasonable wing loading and/or a reasonable flight time.

The electric motor's operation is based on the electromagnetic principle. When electric current flows through a coil it creates a magnetic field with a strength proportional to the current's value, the number of windings of the coil and is inversely proportional to the coil's length. The strength of the magnetic field will further increase by introducing a so-called ferromagnetic material inside the coil.

RC Airplanes: Trainers, Styles, and More

Remote control airplanes account for a large portion of the RC vehicle market and they come in a large variety of styles with their own distinct characteristics and abilities. Each style is built and designed for a specific purpose such as speed, maneuverability, or show. The primary styles of RC airplanes are: trainers, park flyers, racing airplanes, and acrobatic airplanes.

Trainers are designed for beginners and novices and fly at a slower rate of speed which gives the controller more time to react to changes in the wind. A good trainer style airplane will have these basic characteristics: a tricycle landing gear, low center of gravity, and wings that are angled and flat bottomed. Atricycle landing gear means that the RC airplane has 3 fixed wheels which allows for more directional control when taking off and landing then those with the tail dragger style landing gear.A low center of gravity means that the wings are located above the fuselage which helps to keep the plane flying some smoothly. When the wings are located below the fuselage then the center of gravity is high on the airplane and gravity is always trying to make the plane fly upside down. The wings of the RC airplane make up a large portion of its body and should have a dihedral angle which forces the airplane to self-correct into a straight and level flight path if the controls are released during flight. The wings should also be flat bottom which causes the air traveling over the wing to go at a slower pace than the air flowing below the wing allowing the airplane to sustain flight at a slower speed.

Pulsejet Engines - The Beginners' RC Planes Guide

Aircraft model builders have always strived to emulate the full-sized aircraft, as well as their propulsion systems. The word "pulse" engine may be tracked back to around 1880 - 1890 and it is claimed that a Frenchman has build a pulsejet engine in the beginning of 1900 however, it's unknown whether he was successful.

The Germans used this type of engine during the W.W.II to power the well-known V-1 flying bomb. This power concept was eventually proven to be relatively inefficient, terribly noisy and also having a very short lifetime.

The valves on the V-1 engine lasted no longer than 30 minutes continuous use. The pulsejet was therefore abandoned as a full-size aircraft propulsion system. Nevertheless, it has been used on model aircraft by some enthusiasts until now.

A model pulsjet engine is basically made of a tube consisting of a head with a venturi shaped air-intake, a diffuser, a combustion chamber, reed valve plates, a spark plug and an exhaust.

In order to start the engine, a compressed air from an external pump or air bottle is fed to the angled pipe located near the diffuser while a pulsed high voltage supply is applied to the sparkplug. The air/fuel mixture is pushed through the valve into the combustion chamber and ignited, which causes a noisy explosion that closes the valve plates while the expanding gasses escape trough the exhaust. This produces a low pressure inside the combustion chamber that opens the valves and new air/fuel mixture enters the chamber again, which is ignited by the residual heat and gasses from the previous explosion.

The high temperature developed keeps the motor running without the spark plug and the compressed air, which are only needed at the start moment. Some types have no sparkplug attached. The initial ignition is then obtained by introducing external sparking wires through the exhaust. The pipe has an acoustic resonant frequency depending on its length, which must be close to the valves' working frequency in order to get a reliable operation.

The extreme heat developed means that this engine needs a lot of air cooling and cannot stand static running on a test-bench for longer period than about 10 seconds. It must also be mounted outside the model to prevent burning damage to the structure.

Due to the extreme noise and the high temperature involved, this engine is absolutely not recommended for beginners and should not be used near residential areas.