So you’ve crashed your new Multiplex Easystar or Minimag. Now what? Don’t throw your model out, it’s extremely likely that it can be repaired to like-new condition. It turns out that the Elapor™ foam Multiplex planes are built out of is extremely crash resistant, and can even be re molded with heat. Elapor™ is also CA glue safe, making repairs simple and economical.

Gather Parts and Assess the Damage

After a crash occurs be sure to retrieve all the parts, no matter how small. Foam can be fitted back together like a jigsaw puzzle and glued in to place. So you want to make sure that no parts are left at the crash site. Put all the parts you retrieve in a bin and store them in a safe place until you’re ready to begin repairs. It’s generally a good idea to wait for a few hours or days before repairing damaged models. This gives you time to think about exactly what needs to be replaced, and how you would like to proceed.

Repairing Cracked and Broken Foam Parts

Repairing broken foam is very simple. Done correctly, you can hide the cracks and make your model look just like new. Here are the supplies that you will need:

1. Thick CA Glue
2. Clear Tape
3. Popsicle Sticks

Apply a generous amount of CA glue to the broken parts, then use the Popsicle sticks to smear the glue around and cover the entire broken surface. Hold the parts together under pressure and then wrap the clear tape around them so that they stick together firmly. Let the glue cure for at least one hour and then remove the tape. Repeat for all your broken foam parts.

Fixing Bent, Compressed, and Distorted Foam

Unlike Styrofoam, Elapor™ can be heated and re-molded to its original shape. There are two ways to do this, both are outlined below:

1. Hot water method – Boil a large pot of water, and then dip the distorted part for approximately 10 seconds. You will notice all of the foam cells enlarge and expand. This is what needs to occur for the remolding to take place. Using gloves or other thermal protection, bend the heated parts back to their original shape. Smooth out any bumps or surface defects using a metal spoon.
2. Blow Dryer Method – This method works well for smaller dents and bends. Simply take an electric hair dryer (not a heat gun), and gently heat the damaged area for a few seconds. After you see the foam cells start to expand, bend and smooth out the damaged area back to its original shape.

Replacing Electronic Components

Both the Multiplex Easystar and Minimag are compatible with Hitec’s radio components.

Need More Help?

Although we can’t exchange aircraft that have been damaged in a crash, we’re still here for you and can talk you through most repairs. Feel free to contact us and we’ll do our best to help you.

Have you ever wanted to mod your RC airplanes, perhaps to carry an explosive payload? Too bad – it’s illegal. Don’t worry though, here at Draganfly Innovations, we’ve found the next best thing: you can mod inexpensive RC planes to carry containers of inert powder, which will shatter and make a super nifty effect on the ground. All you need are 5 minutes and some common household materials:

What You Need

• Toothpick – We’ll use this to make a mount for the payload, and a mechanism that lets us deploy it remotely.
• Plastic Easter Egg (or similar container) – Plastic Easter eggs work best, because they split in two easily. You can find them at almost every craft store. Improvising here is fine, just make sure that your container is a reasonable size, and will open up with minimal force.
• Cellophane Tape – This mod isn’t permanent, just peel off the tape when your done with it.
• Plastic Drinking Straw
  
• Vortex Extreme RC Airplane – You can get one on our website. Similar models will also work, but if they’re of a different design, you’ll have to adapt these instructions accordingly.
• Talcum Powder, Flour, or any (safe) Powdery Substance – Basically, anything that spreads out in the air and makes a big cloud will do.

How to Mod Your RC Airplanes

1. Start by taking the wing off your RC airplane. You need it out of the way, because your going to be building the drop mechanism on the bottom of the plane. Besides, breaking foam wings is no fun – store it in a safe place until your finished these steps.
2. Cut about a 1 inch length of straw, and tape it to the tail boom, 2 inches back. You want to get the straw aligned parallel to the tail boom, and hanging right on the bottom. What we’re trying to do won’t work if the payload rubs against the tail and gets stuck. You might want to click this picture, to get a closer view.
3. 

   Tape the toothpick to the round end of the plastic egg. The aim is to give the toothpick an upward slant, so that the egg hangs on to your RC airplane under gravity.Try to leave as much of the toothpick as possible free – this gives you a more secure mount. It’s very important not to tape the Easter egg shut, because the whole point is to get it to split open on ground impact.

4. Fill the Easter egg with powder, and then snap it shut.
5. Slide the “bomb” onto your drinking straw launcher apparatus (see the picture on the right), and get the plane ready for flight.

Dropping the Bomb

The Easter egg you mounted is held on the airplane by gravity and wind resistance. To drop it, simply take off as usual, fly to a safe area (free of people, pets, and vehicles), and put your RC airplane in a nose dive. The “bomb” should slide off the mount, hit the ground, and produce a nice puff of smoke. Watch Out: many RC planes have crashed because the pilot was looking at the payload being dropped, and not paying attention to flying. Let spectators enjoy the bomb, and concentrate on landing your plane safely.

Here’s what the result of a properly detonated “bomb” looks like (the best explosion occurs at about 1:12 into the video):

Need RC airplanes for this project? Get a Vortex Extreme online. Perfect for beginners to learn how to fly, and affordable, it makes the ideal first RC airplane.

• Clean Your Transmitter - Everyone loves the way brand new transmitters and other RC equipment looks, but after a few trips to the flying field it can accumulate dust, grass, and other debris, You can make your transmitter look like new by brushing it off with some stiff paintbrushes. Get the dirt trapped in hard to reach places using compressed air, available from most computer stores in canned form. A soft cloth and some glass cleaner solution can be used to wipe off any displays.
• Secure an Antenna – Many RC model airplanes have long wire antennas, which need to be fixed to the fuselage to prevent them from dangling in the wind. Make a secure and adjustable attachment by taking a short (~1 inch) length of fuel tubing, and passing the wire through. Then push a small pinhead into the fuel tubing so that the wire can’t fall out easily. You can then glue the fuel tubing onto your airplanes fuselage wherever it’s convenient. Tighten the antenna by gently pullign on the end.
• Safe Storage for Wings and Fuselages – Keeping RC model airplane wings and fuselages out of harms way can be a hassle. Many hardware stores sell portable shelving units, which you can use to safely store your RC model airplanes. Install the shelves on a wall, but leave off the solid wood planks that create a surface. What you will be left with is a series of protruding beams, that you can set RC model airplane wings and fuselages on. The shelves let you stack several aircraft on top of each other for efficient storage.
• Securing Screws with Silicon – Ordinary silicon gel can be used to prevent screws from vibrating loose. As an added bonus, you can peel the silicon off easily when you need to undo the screw.
• Prevent Parts from Rolling Away  – You can prevent small screws and other metal parts from rolling off your workbench by taking any large, flat container and gluing some magnetic strip material to the bottom. Metal parts will stick to the magnet and will not be able to roll away.
• Remove Thread Lock Compound – Thread locking compounds are great for preventing parts from vibrating loose in flight, but removing screws secured with thread lock compound  can be a pain. Avoid stripping screw heads by first touching a hot soldering iron to the screw for a few moments. The heat will melt the thread lock compound, allowing the screw to come loose easily.
• Cheap Wingtip Protectors – Model airplane wingtips can get scuffed on grass and pavement runways. Prevent this by adding small strips of plastic, obtained from soda bottles. The plastic can be attached using glue or small wood screws.
• Secure Servo Leads – Having a servo lead come off in flight can be disasterous. Prevent this by tying the servo cable in a loose knot after you plug in the leads. This will prevent the cable from coming loose in flight, and removing them is a snap.
• Avoid Pulling The Connectors Off Servos – Pulling the wire off a servo connector is annoying. Prevent this by bending in the ends of ordinary tweezers, to make a tool that can grab on and pull of a servo lead. The bent ends can grab right on to a stubborn connector.

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Like all new aerobatic maneuvers, perform the rolling loop at a high altitude when you first learn it. This ensures that you have sufficient altitude to recover from most mistakes. Try the rolling loop in the direction that you’re most comfortable rolling. After you become more familiar with it, you can roll in any direction you want.

Follow this procedure to perform a rolling loop:

1. As with almost every aerobatic maneuver, begin by climbing to sufficient altitude and facing into the wind.
2. The objective of this maneuver is to execute a round loop and a 360 degree roll at the same time, so increase throttle to full and begin climbing.
3. As you’re RC model airplane climbs, use a small amount of rudder to hold it in a vertical position.
4. Continue to use up elevator and aileron to roll and climb. Control the roll rate so that the RC model airplane’s wings are level at the top of the loop.
5. Decrease the amount of rudder input so that the RC model airplane “falls” over the top of the loop.
6. Decrease throttle, and continue using aileron and rudder to maintain a constant roll rate.
7. Aim to have the wings level again at the cardinal point (the point at which you first started the maneuver.)

Congratulations! You now know how to successfully perform the rolling loop!

1. Download and print one of the free patterns available on the internet. The one that you choose largely depends on your personal building experience, the supplies you have, and the amount of time that you are willing to put into the project. Some plans need to be scaled up or down. If you don’t want to do this yourself most print shops will reproduce and scale images for you.
2. Transfer the paper pattern to the foam core you obtained earlier. There are several ways to do this, but if you want to preserve the plan you can lightly score over the outline with a ball point pen. This indents the foam below and creates a pattern for cutting.
3. Cut out the pattern that you made with a sharp hobby knife, being careful to follow the lines accurately. If you make a mistake round it out using medium grit sand paper and a sanding block.
4. Round out the leading edge of the wind a fuselage by first using medium, and then fine grit sandpaper.
5. Give the wind an airfoil by making three bends along it’s length. Some patterns include the desired airfoil section – so if yours does use it as a reference.
6. Sand some dihedral into the wing and glue the wing halves together using either foam safe cyanoacrylate or hot glue (available in most craft stores.)
7. Assemble the model using your adhesive of choice.
8. Unless your model’s pattern was meant to be glued to the foam – you will probably want to add some color. Spray paint is a great way to decorate your finished model, but be sure to use satan paint – not enamel. Most enamel paints react badly with foam.
9. Mount your servos by cutting rectangular holes in the wings and fuselage, and pressing them in.
10. The brushless motor is usually mounted by on a wooden dowel glued to the fuselage, and the radio and batteries can be secured to one side of the fuselage with velcro.
11. As a last step add the control surfaces and hinge them with clear packing tape.

If you want some free patterns and instructions, check out this RCGroups.com thread. Many foamie fans have contributed great models and posted them for everyone to use. Have fun with your foamie RC model airplanes!

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Choosing a Flying Slope

As it’s name implies, slope flying involves launching an RC model airplane from the top of a slope. Slopes are great flying locations, because wind blowing up the slope causes updrafts which RC model airplanes can use to fly.

If you’re interested in slope flying, the first thing to do is to find a suitable place to fly. An ideal slope has an elevation of at least 100 feet, a gradient of 30 degrees, and is relatively free of trees and other obstacles. Most nearby slopes are unlikely to be perfect, but any slope that is relatively high and steep should do. Almost any RC model airplane with a large wing area will glide well enough for slope flying. Both the Multiplex EasyStar and the Vortex Extreme are well suited to slope flying, and can glide for large distances with their motors turned off.

Launching and Flying the RC Model Airplane

After you’ve found a suitable flying location you can begin slope flying. Most RC model airplanes are hand launched for slope flying, so you may want to read our other article: Hand Launching An RC Model Airplane for some pointers. When hand launching your RC model airplane face into the wind and apply full throttle (if the RC model airplane has an engine). Toss the RC model airplane overhand, and use up elevator to enter flight.

Immediately after takeoff, turn the RC model airplane so that it flies parallel to the slope. This puts the RC model airplane in a position where it can catch the maximum amount of upward airflow. If sufficient wind is present, the RC model airplane should begin to climb gradually. After the RC model airplane has gained sufficient altitude, begin a gradual turn away from the slope. Continue the turn until the RC model airplane is parallel to the slope, and continue climbing. This circuit can be repeated as long as the wind remains constant, and the batteries powering the radio components are charged.

Landing the RC Model Airplane

Landing after you’ve finished flying is challenging due to the sloping ground, so follow this procedure when landing your slope flying RC model airplanes:

1. Approach the top of the hill at an altitude of about 10 feet.
2. Make one wide turn into the wind, and begin your descent so that the plane will land near the center of the hilltop.
3. Continue flying into the wind, and gently let the plane settle on to the ground. Have fun slope flying with your RC model airplanes.

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1. Plan the Takeoff – All takeoffs are performed into the wind. Most flying fields have a windsock near the runway so that pilots can accurately judge the direction and intensity of the wind. Be sure to check the windsock before flying and position your RC model airplane accordingly. You should also look for a landmark (a bush, tree, or other object) over which to complete the initial turn after climb out.
2. Position the Aircraft – Position the RC model airplane on the centerline of the runway so that it’s nose faces into the wind
3. Choose a Pilot Station – Some RC model airplane flying fields have marked positions for RC model airplane pilots to stand on when flying. If this is the case at your location, choose one close to your RC model airplane.
4. Advance the Throttle – Smoothly and rapidly advance the throttle to full. Advancing the throttle quickly gives you better control during the takeoff, because it moves air over the control surfaces faster.
5. Accelerate – As the RC model airplane accelerates down the runway keep it aligned with small taps of rudder. If you are flying a tail dragger, then hold a small amount of up elevator during your initial takeoff roll. This can prevent the RC model airplane from nosing over into the ground.
6. Climb – After your RC model airplane gains sufficient speed pull back gently and begin climbing. Do not climb too steeply, or you risk inducing a low altitude stall. Just hold the RC model airplane in a straight and gradual climb. Correct any bank by tapping the aileron (or rudder) stick briefly. Plan your climb so that you have sufficient altitude to make a turn over the landmark chosen earlier
7. Begin the Initial Turn - After your RC model airplane arrives at the target location, level off and reduce throttle to ½. Turn in the desired direction by banking the aircraft and letting it turn while maintaining altitude.

Take a look at this video, which shows a takeoff done by the above procedure.

We hope that this procedure helps you perform great takeoffs, every time.

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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.

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Phone: 1-800-979-9794 / 306-955-9907
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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.

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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.

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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!

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Phone: 1-800-979-9794 / 306-955-9907
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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.

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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!

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

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© 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