THE WORLD OF MODEL AIRCRAFT

Have you ever wondered what it is like to fly? Haven't you noticed that whenever you see something in the air like a kite, a bird, or airplane you would like to be there? Wouldn't it be great if you could be able to soar the clouds? Well it came to be when two brothers Orville and Wilbur Wright made a successful flight at Kitty Hawk in 1903. For centuries men had been trying to get off the ground but all they could manage was a blimp or hot air balloons. But, the Wrights did it! They were the first off the ground in an airplane. Though the flight only lasted for a few seconds it was the beginning of an era.

A couple of decades after the Wright brothers flight over Kitty Hawk model airplanes began. Model airplanes started as a very basic and uniquely designed aircraft. Their fuselage or body was usually oblong or triangularly shaped and was designed after Lindbergh's plane "The Spirit of St. Louis". Most of the wings were experimental or followed the Wright brothers' airfoil. This was hoisted three to four inches above the fuselage. 1/2A engines made by Cox a well-known manufacturer and dealer of these engines commonly powered them. They were quite small with .07, .011, and .049 cubic inch displacement. They are rather small but they did the job and still do. Most of the early flying was freeflight (this means that they were not controlled by a radio.) This does not mean they did not have radios, they did but they were very crude and rudimentary. An example of an earlier more basic design is called the twin pusher. This is what one looked like.

They used two pusher props. Each one was wound in the opposite direction of the other to counter act the torque from each prop. They had a short wing in the front and a large one in back; and they had each prop mounted in the rear of the model. One thing about airplanes of this time was that they had hand carved props not some high tech glass filled injected molded mass produced factory prop of today. In some aspects they were extreme adventurers into the unknown going only on the knowledge of previous people. They were built from balsa (later in history when it was finally accepted as a good wood to build with.), spruce, pine, basswood etc., fragile glue, and a tissue paper type substance called Silk Span. Silk Span was applied directly on the wing to cover it glued in place then covered with a dope to harden it and color it. I guess you could say it was a really thick paint. Most of the time when they put models together with spruce or pine they used tacks to hold it together and this made them very heavy. What they needed was some progress.

The first radio controlled airplane was built in 1937 by Two brothers with the last name of Good. Their first plane was named the "Guff". The Guff was a big airplane it had an 8-foot wingspan but only weighed around 8 1/2 pounds. The plane had only two frequencies, one for the rudder and the other for the elevator control. The Guff's servos were mounted directly on the tail surfaces. Servos are electric motors that activate the turning of the rudder, elevator, ailerons, and pushing the throttle up or down. Servos of that era were quite large and had very little torque or pushing power. An outlet on long extension cord powered the transmitter. It is now on permanent display at the Smithsonian Institution in Washington.

THE NEW WORLD

Now airplanes have evolved to more complex machines with materials, coverings, woods, engines, and radios. Many of which are to the point were they don't need to be advanced any further. For example we do not use the material called Silk Span anymore. Except when doing historical models and restoring models that used it. Modelers have now developed the engines they use into miniature precision monsters of power putting out around eighteen to nineteen thousand r.p.m. With as little as a quarter cubic inches displacement. Keep in mind this r.p.m. is a standard for all, they aren't even modified yet. With modification they can reach a much higher r.p.m.

Modern Aircraft engines are two- or four-stroke, reciprocating engines. They use what's called a glow plug in stead of a spark plug. A glow plug works by a battery heating up a coil inside the plug with the end exposed to the gas. When compressed the gas ignites and heats the plug without the battery thus it keeps the engine going. One thing that is different is the gas instead of using regular gasoline we modelers use what is called glow fuel. Glow fuel is an altered methanol with oil and nitro gas mix they call this gas nitro-methane. Typically, engines range in displacement from .049 cubic in. to 1.2 cubic in. (.80cc to 20cc). With this in mind you can take your pick of the aircraft and the size of the engine. There are six type of engines that modelers use they are ABC / non-ringed, BB, Four-Stroke, Lapped, RE, and U/C or C/L.

ABC or non-ringed engines these are the most common, and ABC stands for aluminum, brass, and chrome or a composite such as nickel. They have no piston rings and rely on a very tight piston to cylinder fit to obtain a piston cylinder seal.

BB- These letters designate that the engine has ball bearings to support the crankshaft of the engine. This allows the engine to run smoother and last longer.

Four-Stroke- Really the only advantage is that they are quieter and can swing a larger prop than a two-stroke of similar size. Fuel economy is better. Usually is the choice engine for modelers who fly bigger aircraft.

Lapped- Same as ABC. Lapping is a method of manufacturing an engine without using piston rings to maintain compression.

RE- stands for engines that have rear exhaust. Usually engines are side exhausts.

U/C or C/L- Control line engine that runs full bore until it's out of fuel.

The Glue World

We also have new types of glues they're called cytrocrynalics. They are very strong and have great bonding abilities. Some are used to fill gaps and some are used to bond pieces that are tightly fit together. I like to use the thick glue myself because of its strong bonding power. In fact the thin glue dries and bonds balsa so fast it burns the wood but not if you were actually burning it. It just bonds the pieces so fast so it produced enough heat to give a whitish translucent smoke.

Price World

Here are a few things you may want to know. The price tag on one of these planes is anywhere from as little as $100.00 to as much as $1000.00 on assembling the basics. Average for a beginner is anywhere from $200.00 to $300.00.

What's that? You want to know how fast they go. Well, trainers usually cruise at 25-30 mph and can fly as slow as 12-15 mph. However once you pass the trainer stage you could have some fun with off-the-shelf models that can go as fast as 200 mph or more.

A group you should join when you get into the hobby is the AMA. It stands for The Academy of Model Aeronautics. This year it is the 60th anniversary of this organization. It isn't just that though it is also an insurance agency that you can utilize for your benefit if you hit someone or something with your airplane. Right now they have about 137,000 members. Here's the divided interest of the modelers radio control at 91% (about one fifth of that is interest in electric power), control line 1.16%, free flight 1.16%, indoor 0.1%, scale .6%, and general interest about 6%.

If you would like any more information or you would like to get involved in this hobby please contact me.


© Matt Barnadyn 1998