RC Airplanes

You should always balance your RC model airplane propellers before using them. Running your RC model airplanes with properly balanced propellers will increase motor or engine lifespan, prevent fuel from foaming, and even extend the life of your electronic components. This article will show you how to balance your RC model airplane propellers using simple and inexpensive equipment.

The best way to balance your RC model airplane propellers is to use one of the many prebuilt balancers available. Blade balancers usually come in two varieties:

1. finger prop balancers – sufficient for most modelers, you can get good results using a simple blade balancer for 5 to 10 dollars depending on the supplier. Great Hobbies has a balancer which works sufficiently well to balance most model airplane props.
2. magnetic prop balancers – produce highly accurate results and are usually more expensive than finger balances.

Use the blade balancer by unscrewing the two metal rings and then placing your propeller in between them. Tighten the metal rings so that the prop doesn’t move and support the entire apparatus with one finger tip on each hand. The prop is balanced if it remains motionless. If it tips forward or backward then you will have to adjust it according to the following procedure:

1. Mark the heavy side (which tips downwards) with a felt tip pen.
2. Sand one side of the propellers heavy end with medium to fine grit sandpaper. Do not sand the propeller tip – this will cause a dynamic imbalance when the engine is running.
3. After removing a very small amount of material from the heavy side of the propeller, test it again using your blade balancer.
4. Repeat steps 2 and 3 until the propeller remains motionless while held in the blade balancer.

This procedure will balance your propeller accurately enough to eliminate the most severe vibration during flight. 3D aerobatics, racing, or other demanding flying requires propellers to be balanced more precisely. You can get a higher end magnetic balancer for 20 to 30 dollars. It’s usage is about the same as the finger balancer except that the propeller is held between two magnets.

Check your propeller’s balance using the above method and be sure to follow the manufacturers instructions when putting the propeller in the balancer.

——
© Draganfly Innovations Inc.
Phone: 1-800-979-9794 / 306-955-9907
Email: info@rctoys.com
Web: www.rctoys.com
RSS: www.rctoys.com/pr/feed

We all know the phrase “a good landing starts with a good approach”, but what exactly does it mean? This article will answer that question and show you how to consistently make accurate approaches and great landings with your RC model airplanes.

Mastering the Approach

If you can approach the runway straight on and at the right altitude, then landing will be extremely easy. Follow this procedure to get your models properly lined up for landing and avoid some of the common mistakes which can lead to crashes:

1. Before flying, walk to the center line of the runway and face into the wind.
2. Try to judge the best location to start your descent; and look for a tree, hill or other easy to see object near the spot that you choose.
3. Plan to turn towards the runway as soon as your plane crosses the reference line you chose.
4. Judge how much wind there is, and correct your approach path during during your descent as needed.

One major mistake that pilots make is beginning their descent so that the RC model airplane doesn’t face into the wind. When this happens, the wind blows the airplane off course and you will have to correct for it.

You can prevent having to make any corrections at all by properly lining up the RC model airplane with the field before you start your descent. The key is to “crab”, or turn the plane slightly, into the wind so that it flies straight. This way, you can focus on maintaining a good approach speed and altitude, instead of constantly correcting for deviations caused by the wind.

We hope that this article helps you make great landings every time.

——
© Draganfly Innovations Inc.
Phone: 1-800-979-9794 / 306-955-9907
Email: info@rctoys.com
Web: www.rctoys.com
RSS: www.rctoys.com/pr/feed

There are many fun games that you can play using RC model airplanes. This article shows you how to set up and play some of the most interesting ones.

Aerial Combat

You can simulate aerial combat with your RC model airplanes without excessive risk to your models. Here’s how:

1. Find as many friends with RC model airplanes as possible.
2. Divide the available RC model airplanes into teams
3. Attach different colored streamers to each RC model airplanes tail, depending on which team that it’s on.
4. Have all the RC planes take off at once
5. The object of the game is to use your RC model airplanes propeller to cut the streamer off of our opponents.
6. After a set amount of time all of the planes land and the length of their streamers are measured. The team with the most streamer remaining wins.

This game can be played with any number of RC model airplanes, but keep in mind that the risk of a collision increases with the number of RC model airplanes flying.

Flying the Limbo

This is one of the easiest games to play, but it’s also the most risky. To play,simply find a large football or soccer field and fly your models through the goal posts. Make sure that you are allowed to fly your models in the field that you’re using, and that there are no people in the field that could get hurt -should the airplane crash.You can also construct a makeshift goal post out of PVC pipe, found in most hardware stores. Cut the pipe to a decent length, and then friction fit it together using PVC fittings.

Bomb Dropping

RC pilots frequently modify their aircraft to carry and drop payloads. If you would like to add this ability to your RC model airplane, follow this procedure to construct a launching apparatus:

1. Find a rectangle of balsa wood, at least as long and wide as the payload that you intend to carry on your RC model airplane.
2. Horizontally mount a spare servo to the end of balsa wood. Make sure that the servo arm points upwards and rotates 90 degrees when activated.
3. Stretch a rubber band over the two corners of the balsa rectangle opposite the servo, and then loop the rubber band over the servo horn.
4. Mount the whole apparatus on your RC model airplanes fuselage, and connect the servo to your receiver.

After the servo moves, the rubber band slips off the horn. If you place your intended payload under the rubber band, you can drop it from your RC model airplane at the flick of a switch. Take a look at this picture, which shows one such design completed and loaded with plastic parachute toys.

You can make bombs to drop out of Styrofoam cups, rubber cement, and talcum powder. Here’s how:

1. Place one Styrofoam cup on a flat work surface, and fill it with a few tablespoons of talcum powder. Take a small paint brush, and coat the Styrofoam cups rim with a small amount of rubber cement.
2. Place another Styrofoam cup on top of the first, lining up the rims.
3. Let the cups dry
4. Take a hobby knife and cut a cross section into one of the cups.
5. If you like, spray paint the bomb and add cardboard fins.

After the bomb hits the ground, the cross section that you cut into the nose will cause it to shatter, releasing the talcum powder it contains. When it works, this looks a lot like the cloud of smoke and debris that real bombs leave after exploding. After you drop the bomb, be sure to watch your airplane and not the resulting cloud of powder.We hope that you enjoy playing these games with your RC model airplane. Be safe,and have fun.

——
© Draganfly Innovations Inc.
Phone: 1-800-979-9794 / 306-955-9907
Email: info@rctoys.com
Web: www.rctoys.com
RSS: www.rctoys.com/pr/feed

Many RC model airplanes lack a conventional landing gear and need to be hand launched. This article will show you how to properly hand launch an RC model airplane.

When you’re learning to fly try to find a hill to launch your RC model airplanes from. This will give you a bit of altitude right after takeoff, which provides more room to maneuver during the initial climb. Follow this procedure to successfully hand launch an RC model airplane:

1. Turn both the transmitter and the receiver on.
2. Hold the RC model airplane at it’s center of gravity (balance point) with your throwing hand and hold the transmitter in your other hand.
3. Make sure that the RC model airplane’s nose points downward slightly and that the wings are level.
4. Increase throttle to full.
5. Toss the RC model airplane forwards like you would throw an overhand baseball.
6. As soon as the RC model airplane leaves your hand, quickly move your hand to the transmitter and begin flying.
7. The initial climb should be straight and gradual, using only small control inputs.

Some RC pilots prefer to launch their aircraft by taking a running start. There is nothing wrong with this method, just make sure that there is nothing in your path that you can trip on. Take a look at this sequence of pictures, which shows what a good hand launch looks like.

Now that you know how to properly hand launch an RC model airplane, get one on RCtoys.com and go flying!

——
© Draganfly Innovations Inc.
Phone: 1-800-979-9794 / 306-955-9907
Email: info@rctoys.com
Web: www.rctoys.com
RSS: www.rctoys.com/pr/feed

Introduction

RC jet engines represent some of the most impressive technology that the RC industry has ever created. RC jets are always an amazing sight at the flying field, because they look and sound just like the real jets you find at airports and military airfields. In this article, we will take a look at how model jet engines work, and show you the differences from full scale jet engines.

Before you go out an buy a jet, be warned that RC jets are some of the most complicated, expensive, and difficult RC model airplanes available. You will need both many hours of flying experience and a huge budget to successfully own and fly an RC jet.

This article is about real jet engines which burn kerosene (or jet A1), not the electric ducted fan models frequently found in hobby stores. EDF jets are great models to fly, and some are capable of advanced aerobatics, but they are not to be confused with real RC jets using real jet engines.

How Full Scale Jet Engines Work

In order to understand how model jet engines work, it is helpful to examine the full scale engines used by airliners and other jet aircraft. A jet engine is a device which operates inside a fluid (in most cases air), and expels it at high speed achieving a propulsive effect. The mechanics of jet engines are best represented by Newton’s laws of motion, specifically: “For every action, there is an equal and opposite reaction.” This means that the reason jets go forward is because they expel air backwards, faster than it came in. This basic principle applies for all types of jet engines.

But how do we achieve the movement of air needed to propel an aircraft? We know from high school chemistry that the volume and the temperature of any gas are proportional. Because of this, when air is heated, the volume increases. If the air is held in a container (the combustion chamber of a jet engine), then the pressure will also increase. Releasing the heated gas will result in an exit speed greater than the speed at which the air entered, creating the backwards flow of air needed to travel forward.

Interestingly enough, rockets are considered to be a type of jet engine. The only difference between a rocket and a conventional jet engine is that the rocket operates in a vacuum, and thus needs to take both fuel and an oxidizing chemical with it. The discussion of rockets and other exotic jet engines is beyond the scope of this article, so we will limit our investigation to three of the most common designs. These jet engines are listed in order of complexity, and all were used in full scale aircraft at some point in time.

The Pulse Jet

The pulse jet is one of the simplest jet engines, consisting of little more than a pipe and a fuel source. Pulse jets were used by Germany during World War II to propel primitive cruise missiles (V1 flying bombs). A pulse jet works by igniting a fuel air mixture in high frequency bursts. A typical pulse jet cycle operates as follows:

1. Air is allowed to enter the combustion chamber, and fuel is simultaneously added.
2. The intake valve is closed.
3. Ignition is triggered, resulting in an outward flow of air and low pressure inside the combustion chamber.
4. The valve is opened, and new air rushes in due to the low pressure in the combustion chamber.

This cycle repeats during the entire operation of the engine.

Pulse jets are not very efficient, and are extremely loud. Because of this they are not often used in full scale aircraft, but hobbiests often build them due to their design simplicity and lack of moving parts. In some cases, pulse jets are built to small dimensions and used on RC model airplanes.

Turbojet Engines

More sophisticated jet engines use turbines to compress the air fuel mixture before igniting it. A turbine is a device which consists of sets of moving blades attached to an axle. If the turbine blades are spinning, they will move air through themselves and towards the back of the vehicle. This figure shows a moving turbine, spinning on an axle.

The operation of a turbojet is represented in this figure.

Unlike pulse jets, turbojets lack a repeating cycle (the engine operates continuously). There is a sequence of events that occurs during the engines operation though, so we list them here in chronological order.

1. Air enters the turbine and becomes compressed.
2. The compressed air is routed to the combustion chamber, where is is mixed with fuel.
3. Ignition occurs, and the resulting hot air is allowed to exit the jet engine.
4. Before leaving the engine, the hot air is forced through a gas turbine, which drives the compressor used in step 1.

Turbojets are far more efficient than pulse jets, because some of the energy produced by the combustion process is reused

Turbofan Engines

Even though turbojet engines are more efficient than pulse jets, they are not often used in subsonic aircraft because of the noise they produce. Turbojet engines are well suited to high speed operations, exceeding the speed of sound. They become less efficient at the subsonic speeds which airliners and other commercial jet aircraft operate at.

The turbofan design operates on exactly the same principle as the turbojet engine, but instead of routing all of the intake air through the combustion chamber a small amount is allowed to exit unburned. Instead of being mixed with fuel and burned, some of the cool air is mixed with the exhaust, reducing the exhaust speed and increasing fuel efficiency. This figure illustrates the operation of a turbofan jet engine:

How Model Jet Engines Work

RC Model airplane jet engines work in exactly the same way as the full scale ones discussed above, with the exception of the air compression. Instead of using an axial turbine compressor, RC jet engines use a centrifugal compressor. A centrifugal compressor propels air outwards after it enters the engine, causing it to hit the engine case and be compressed. Centrifugal compressors need fewer moving parts than axial turbine compressors, and are more efficient for small applications. Many small full scale jets use centrifugal compressors for the same reasons.

Here is a picture of a typical RC model airplane jet engine, mounted on top of an RC model airplane.

RC jet engines operate on kerosene, exactly the same fuel that full scale jet engines use. Ignition is achieved with a small glow plug, like those found on two and four stroke RC model airplane engines.

——
© Draganfly Innovations Inc.
Phone: 1-800-979-9794 / 306-955-9907
Email: info@rctoys.com
Web: www.rctoys.com
RSS: www.rctoys.com/pr/feed

Every RC model airplane has a center of gravity, or balance point, and it must be in the correct location for the RC model airplane to fly well. This article will show you how to correctly balance your model. Here is a general procedure that you can follow when balancing a new RC model airplane:

RC Model Airplane Fore and Aft Balance

1. Look at the plans or instructions that came with your RC model airplane. They will tell you where the correct balance point is. In most cases, the correct balance point lies on or near the main spar of the wing.
2. Depending on the size of the RC model airplane, you may need a friend to help you with this step. Install the RC model airplanes wing, and balance it on two finger tips, placed several inches away from the fuselage.
3. Move your fingertips so that they both lie on the recommended balance point.
4. Check to see if the RC model airplane balances. If it is correctly balanced, then neither the nose nor the tail will tip forward or backward.
5. Assuming that it is not correctly balanced, take off the wing and shift equipment inside the RC model airplane forwards or backwards. Correct a tail heavy balance by shifting equipment to the nose, and correct a nose heavy balance by shifting equipment to the tail. If you cannot get the RC model airplane to balance correctly by shifting the internal parts, then you will need to add ballast to the nose or the tail.
6. Find a suitable ballast material (like lead) and secure a small amount to the fuselage.
7. After making these adjustments, do step 4 again and see if the RC model airplane balances correctly. If it does not, add more weight to the nose or tail and try again.

Please note that it is far better for the RC model airplane to be slightly nose heavy than tail heavy. A tail heavy RC model airplane will fly in a chaotic, unpredictable manner, almost guaranteeing a crash.

RC Model Airplane Lateral Balance

After completing the above procedure, your RC model airplanes fore and aft balance should be correct. This procedure will show you how to balance the RC model airplanes roll, so that it doesn’t need much trim to fly straight.

1. Loop some string around both the motor shaft and the tail.
2. Suspend the RC model airplane by holding these string loops.
3. Does the RC model airplane rotate? If it does, add some ballast to either wingtip until it stays still while suspended.

Congratulations! You now have a correctly balanced RC model airplane!

——
© Draganfly Innovations Inc.
Phone: 1-800-979-9794 / 306-955-9907
Email: info@rctoys.com
Web: www.rctoys.com
RSS: www.rctoys.com/pr/feed

Now that you know how to perform basic and intermediate level RC model airplane aerobatics, you can progress to the most advanced maneuvers. This article lists some of the most interesting advanced aerobatic maneuvers in order of difficulty.

Immelmann Turn

The Immelmann turn is a type of aerobatic maneuver named for World War I fighter pilot Max Immelmann. When done precisely, the Immelmann turn is a very crowd pleasing maneuver, and can be used in combination with a wide variety of other aerobatics. Perform an Immelmann turn by using full throttle, turning the aircraft into the wind, and then pulling up into a vertical climb. When climbing, use the rudder and elevator controls to keep the aircraft climbing in a straight line. After gaining a significant amount of altitude pull back on the elevator to enter inverted flight. Keep the wings level, and execute a sharp 180 degree roll, bringing the aircraft back to straight and level flight. The net effect of this maneuver is that the RC model airplane is higher, and facing the opposite direction then it was during the start of the maneuver. Take a look at this picture, which shows the different parts of an Immelmann turn:

Split S

The Split S is basically the same as an Immelmann turn, but performed in the opposite direction. As always, begin by turning the aircraft into the wind. Then enter a vertical dive. Pull out of the dive by applying more down elevator, so that the aircraft levels off and enters inverted flight. As with the Immelmann turn, exit inverted flight by rolling 180 degrees in a left or right direction. This figure illustrates the different parts of a Split S:

Cuban Eight

A Cuban eight is one of the most challenging, and interesting, aerobatic maneuvers to perform. Performing a Cuban Eight involves making the airplane follow a vertical path resembling a horizontal eight in the sky. Make sure that you perform this maneuver at a high altitude, this is not to be attempted at twenty feet off the deck.

Start by facing into the wind, and applying full throttle, then pull up and perform a graceful half loop (1). Don’t level off after reaching the top of the loop (2). Instead, continue to use up elevator until the RC model airplane enters an inverted 45 degree descent (3). Wait until the RC model airplane reaches the midpoint of the eight – or about halfway up the first loop, and then perform a crisp 180 degree roll (4). Keep in mind that the RC model airplane will be inverted before you perform the roll.

After performing a roll, level off from the 45 degree descent and pull up again (5). Perform another half loop (6), and then begin another 45 degree descent (7). Wait until the midpoint of the eight (8), and perform a 180 degree roll like in step 3. After that, gradually level out and enter straight and level flight (8).

Ideally, the Cuban eight should be completely symmetrical along both the horizontal and vertical axis.

Congratulations! You can now perform advanced RC aerobatics!

——
© Draganfly Innovations Inc.
Phone: 1-800-979-9794 / 306-955-9907
Email: info@rctoys.com
Web: www.rctoys.com
RSS: www.rctoys.com/pr/feed