Select Radio Transmitter Before Make a Drones

Transmitter (TX) and receiver (RX) are one of the first things that must be owned before assembling Racer Drones, Quadcopter, RC aircraft and other RC Assemblers. This can sometimes confuse RC beginners how to choose Radio Transmitter before assembling. For this reason, in this short article, we will explain how to choose the right Radio Transmitter and not to choose the wrong one.
Radio Transmitter (radio transmitter or TX) is a device that allows pilots to control aircraft, drones, aircraft and other RC without the need for cables. The signal / command is then received by the radio receiver (RX) which is connected to Flight Controller. below are things we need to pay attention to before buying a Transmitter.Channels

1. Channels

The number of channels determines how many actions can be controlled in a controlled Drone, aircraft or Quadcopter. For example, throttle, yaw, pitch, and roll, each requires 1 channel. And as you know, it takes a minimum of four channels to control a quadcopter which is used to control (pitch, roll, throttle, yaw). But for larger quadcopters hobby classes, we usually need more channels to control gimbals, servo and so on.

It is generally recommended to have at least 5 or 6 channels for quadcopter, drone or RC plane. Other channels 1 or 2 can be used to turn on / off or switch to different flight modes.

2. Modes

There are 4 different TX modes, mode 1, mode 2, mode 3 and mode 4. basically the difference is the different configurations of the two right and left sticks. Mode one has an elevator control on the left stick and throttle on the right stick. The second mode is the most common for quadcopter because one stick represents the movement of your quadcopter. That is the elevator control on the right stick and throttle motor in the left. the right stick is on both axes, while the left stick only centers on the yaw axis (left / right direction) slides in the throttle axis (up / down) to allow constant throttle. while mode 3 and mode 4 are very rarely used in the world of RC aircraft. for that choose Transmitter with mode 2 or mode 1 for Aircraft like FixWing Drones and so on.

3. Frequency

The 2.4GHz system is a new technology, and currently the most popular frequency for Aircraft and ground RC this is the RC standard after it made a new protocol that introduces frequency hopping technology that allows users to not have to worry about choosing frequencies or messing up with the same channel from other pilots . Antennas are smaller and easier to carry, but usually with shorter distances than the frequency of 27/72 MHz.

     All RadioTransmitter manufacturers switch to the new protocol hopping channel which makes the RC very easy to maintain and use. Software that is constantly updated to scan the best frequencies used and if it detects any interference, automatically switches to another available channel. This is done many times per second so you have never experienced glitches or radio problems which have been a big problem in the RC industry for years.

4. Radio Receiver

Transmitters are generally equipped with Receivers. It is important to note that TX only works with radio receivers (aka RX) from the same manufacturer with the same frequency and the same protocol. For example, if you buy the Frsky Taranis Transmitter, you must use a Frsky receiver, or another compatible Frsky receiver. So before buying the receiver, read the specifications of the Receiver first, whether it is compatible with the Transmitter that we have / buy.
  There is a consideration of the recipient protocol used and the technology applied, such as PWM, PPM and SBUS. In general, SBUS is better than PPM, while both are better than PWM because the number of connections is needed. for that it is recommended to choose a receiver that supports ppm and pwm or pwm and sbus and adjust it to your needs for example Drone Racer select the small size and support the ppmdan protocol or SBUS Register the best SBUS CPPM receiver


What drone pilots see while they are flying, are the low latency video from analog FPV cameras. To choose the best FPV camera for your multirotors, there are a few things to consider which we will discuss in this post.

FPV camera is one of the most important parts of a quadcopter FPV setup. Real-time image from the camera is broadcast through a video transmitter. Regardless what video transmitter you have, the image you see on the FPV display is only as good as your FPV camera. in this post I will give a tutorial on how to choose an FPV camera that fits your drone needs

The Types of Imaging Sensor

CCD and CMOS are two main types of image sensors in FPV cameras, each with unique characteristics and advantages.

CCD is an older technology and used to be the go-to image sensor for FPV cameras. Nowadays most new FPV cameras use CMOS and they are constantly getting better. Here is a summary of the pros and cons, for more detail check out this post about the differences of CCD and CMOS.


  • Less jello effect in footage due to global shutter
  • Less digital noisy in low light
  • Generally warmer colour


  • Generally lower in latency (the good ones)
  • Higher resolution, but also can have more digital noise
  • More natural image colour
  • Low light / Night FPV cameras tend to use CMOS sensors
  • Generally cheaper to make – therefore the cheapest FPV cameras are usually CMOS
  • More susceptible to jello due to rolling shutter

Aspect Ratio

There are 2 aspect ratio to choose from in FPV cameras, 4:3 and 16:9. Aspect ratio has nothing to do with resolution, it’s just the different screen shape. 

4:3 is more square and has the shape of an old CRT TV while 16:9 is longer like a modern computer monitor.

One isn’t always better than the other, it all comes down to which ratio your FPV goggles or display supports. If you have a 4:3 camera, but your goggles is 16:9, the image will appear stretched. If you have a 16:9 camera but a 4:3 display, the image will appear squashed.

Aspect ratio isn’t directly related to the peripheral view, e.g. 16:9 camera doesn’t necessarily give you a wider field of view. It actually depends on the lens and image sensor of your camera, which we will talk about later.

But it’s worth knowing that CMOS sensors have a native aspect ratio of 16:9, while that of the CCD is 4:3. Some CMOS cameras allow you to choose between 16:9 and 4:3 in the setting, but the 4:3 is achieved by chopping off the sides from a 16:9 image, and therefore you will get a smaller field of view in 4:3.

Lens Size

FPV camera lenses are different in two main things: focal length and thread size.

Focal length changes the field of view (FOV) of the image, the lower the focal length, the wider the FOV. To give you some idea, here is a rough estimation :

Wide Dynamic Range (WDR)

Wide Dynamic Range (WDR) is a technology that aims to improve image detail under extreme lighting conditions where both bright and dark areas are present in the same frame.

As you can see the image on the left it’s under exposed, you can see the sun and clouds very well, but the tree and bushes are all dark. On the right we have an image that is slightly over exposed, the trees are all visible now but the sky is blown out. The image in the middle represents the best wide dynamic rangeof the three images, you can see the clouds and the car at the same time.

Once you understand the concept you will begin to appreciate the importance of WDR capability in FPV cameras because it helps you see better when flying. Most FPV cameras have some degree of WDR, but the WDR performance can vary.

FPV Camera Resolution (tvl)

TVL (TV Lines) is what manufacturers use to measure analogue FPV camera resolution.

The number is based on how many alternating black and white lines can be displayed in the image horizontally. A 600TVL camera means it can display 300 black lines and 300 white lines alternately in one frame. The more TV lines, the better definition image you can get out of the camera. Commonly seen FPV cameras TVL are 600, 700, 800 and 1200.

However higher TVL doesn’t always give you better image due to the limitation of analog 5.8Ghz video transmission, as well as your monitor or FPV goggles. For example, 1200TVL is not going to be twice as sharp comparing to 600TVL in an analogue FPV system.

There is no easy way to verify the TVL spec claimed by manufacturers. So don’t be overly concerned about this number when buying an FPV camera, and base your decision on the actual image quality.

How to Detect Lipo Battery Health

We discussed how to dispose LiPo batteries, but we still haven’t touched on when we should throw them out. So in this article I are going to talk about how I determine if a LiPo battery should be thrown away.

The Average Lifespan of a LiPo Battery – Discharge Cycles

If you are lucky enough not to break your LiPo battery before its end of days, it should have an average lifespan of about 400–500 cycles. One cycle means a battery being fully charged and then discharged.

Of course this also depends largely on factors like how much “abuse” you put your batteries through, and how you handle them on a daily basis.

500 cycles might sound a lot, but for us flying mini quad, it’s extremely likely that we damage them way before we hit that number

Internal Resistance

One useful battery health indicator would be internal resistance (IR). As explained in my LiPo battery guide, IR determines how effectively the battery can deliver the current to your quadcopter. High IR means lower performance, and more heat generated during charging and discharging.

Each cell in the LiPo battery has its own IR value.

New batteries should have a relatively low IR, and it increases during the use of the battery. IR can rise more rapidly when:

  • Over-discharging (e.g. below 3V per cell) and overcharging (e.g. above 4.2V per cell for non-HVLi)
  • Pushing the battery too hard by discharging at a current higher than it’s rated for an extended period of time
  • Overheat

Physical Condition

A visual examination of your LiPo battery can help you determine if it should be replaced.

LiPo batteries used on drones can become deformed in a crash since they are exposed on the outside of the frame. Some people take the risk carry on using these dented batteries without much of a problem. But the risk of fire increases so I’d personally just dispose them.

Your batteries can also become “puffed” after some abusive uses or they are just simply getting too old. Perhaps it’s not as bad as the one in the picture below, but you might notice it’s getting fatter than it was, this is a sign of puffed/swollen LiPo.

Unbalanced Cell Voltages

It’s pretty normal that the cell voltages are slightly different after a flight, maybe one is at 3.55V, one is at 3.59V, and another at 3.61V… The point is, they should all be within reasonable range.

You should be cautious when the gaps grow. When the internal resistance of particular cells are higher than others, they discharge slower and therefore have a higher voltage remained at the end of the flight. Eventually this might lead to over-discharging of other cells in the battery and cause swelling.

This is also why you should always “balance charge” your batteries in case of over-charge.

Check Temperature While Charging

If your battery gets warm during charging, then it’s a very, very important sign that your battery might have a problem. LiPo batteries shouldn’t get noticeably warm when charging at reasonable rate i.e. 1C or even 2C.

Save the Lipo Over Battery Discharged

Beginners RC or lipo users usually experience it when playing rc airplanes, rc boats, rc dron or r / c car too busy and forget not to use voltage sensors such as low voltage alarms or the like sometimes too busy playing until suddenly the rc stops or falls and new Be aware that if they run out of fuel (over discharged) what happens afterwards can be worse than we know, lipo will not be able to be charged or it will even become bloated if it is not immediately handled If you want to try to save your empty LiPo battery with instructions in this article, do it at your own risk.

Remember the longer you let the LiPo battery run out in case this is over discharged, then the battery’s poor performance will increase, it will become bloated and other bad things. So when this accident occurs, the out-of-voltage LiPo battery is measured at a total of 1.9V (usually 0, 63 V per cell). lipo charger can not recognize the battery and cannot charge Do not let Lipo take too long to empty do this immediately we must first increase the voltage in each cell to a higher voltage (above 3V per cell) by connecting to a digital charger as usual but setting the charger using the Ni-MH type, the two detached batteries check if the lipo is at 3 volts per cell if it has been set to lipo mode and reconnect your Lipo charger. You will recognize your empty lipo battery again. So, that’s what we did, if you decide to try it, do it very carefully and do it at your own risk Tools and Materials: digital lipo charger support nimh, banana to xt60 cable & empty LiPo battery

Steps 1

So first of all, you need a digital charger that has a feature that can charge NiMH batteries. Some LiPo chargers can also charge NiMH, such as Turnigy acuucel6. Connect the main battery connector to the charger, and the contents of the LiPo over are discharged with the lowest possible current, for example with a current of 0.1A. usually it only takes a few minutes to increase the cell voltage back to 3.0V. we recommend to stop charging once the voltage reaches around 3V-3.3V, do not fill it with long mode too long After the steps above I then test it with a normal LiPo charger mode and finally be able to read the over-discharged LiPo battery that has been restored. finally we used the Lipo recharge feature to fill the Lipo battery with full capacity, and managed to recover the dead battery.

Step 2

There is a second way to deal with over-discharged LiPo, which is a little more necessary to be careful because otherwise you will burn the battery or even your house hehe but this method is very helpful too by using another lipo that is still sane and still contains a full charge but you must be more careful in this way because it only takes a few seconds to do it differently from the previous method which takes several minutes tools and materials: Black red jumper cable to taste, empty lipo battery, normal battery fully charged.

Prepare an empty lipo battery (target over discharged), prepare another lipo battery that is still normal and fully charged with the assumption that the two batteries must have voltages such as the 3s, 2S, 4S, 5S and 6S use the over-discharged LiPo rescue battery which has small capacity prepare a rather large jumper cable the size of the xt60 hole then connect the black cable (-) to black (-) on the target then the last one connect the positive (+) cable to the positive note that connect the positive cable in 3-5 seconds then immediately off because the cable can be very hot after that connect the original lipo battery to an ordinary charger then the battery can be used as usual for those of you who want to learn more about LiPo battery care see the following article Caring for LiPo to last years

An Easy Way To Set up PID Flight Controller

Many configurator software such as Raceflight, Betaflight, KISS and others allow users to set up PID Flight Controller to improve flight performance. In this post we will explain what PID is, how it affects the stability of your Quadcopter or Drone, and an easy way to adjust the PID on your quadcopter. After reading this PID guide, I also recommend continuing to try and read the deeper PID adjustment guide. because in this article we explain it in a more practical way.

PID is a function in the flight controller that can be set via the configurator. the principle of reading data from sensors, and telling the motor how fast they need to spin. Another word is how stability can be achieved on a quadcopter. PID is proportional-integral-derivative. The PID controller is a loop control system that tries to get accurate results close to the desired results by adjusting the input. The error is given feedback / response, and the same process is repeated

P depends on the current error, I is the accumulation of previous errors, whereas D is the prediction of future errors based on the current level of change. To master any control over a Quadcopter: First we need to measure the angular level of the quadcopter (how fast the quadcopter rotates in each axis) Knowing what desired angle level we want from squared, we can estimate the error We can then apply the 3 control algorithms for errors, to get the next output for the motor which aims to correct the error. That is just an “academic description” of how the PID controller works. In practice, each of the three parameters gives several different effects on flight characteristics and stability.

This parameter is a number that we can play. They are basically just coefficients of the 3 algorithms above. The coefficient changes the effect of each algorithm on output. Here we will see the effects of these parameters on quadcopter.

P Gain

Is the most basic value in PID settings, because Quadcopter or Multirotor can fly and stabilize only with P gain without the other two parameters (I and D). This coefficient determines the strength in the correction. The higher the coefficient, the more sensitive and strong the quadcopter reacts to changes in each angle. If it’s too low, the quadcopter will look slower and softer, it’s difficult to stay stable. One negative impact is that the P gain is too high is too much correction and there is oscillation in the Quadcopter.


This coefficient affects the exact position of an angle. Higher profits are especially useful in windy environments. If it’s too low the Quadcopter or Multirotor will drift away with the wind. However, when I get too high, the quadcopter starts to feel stiff and doesn’t respond to the RC properly. This is the same as the slower reaction and the effect of decreasing P gain. In more extreme cases if the excess I, the quadcopter will oscillate at a lower frequency.

D Gain

    D gain works as a dampener and reduces over-correcting and overshoots caused by P on Flight Controller. It makes your quad fly smoother and has the potential to minimize the oscillations that have occurred before too. But excessive D values ​​can cause oscillations in quadcopter because the noise in the system will be greater. In an effort to make your quadcopter fly smoother, Brushless Motor will spin faster or slower at very fast speeds so that Brushless Motor cannot last, and eventually cause the motor to overheat or sometimes burn, then give D value to just around 20 ( at BetaFlight) don’t give too large a value.

How to Choose the Best Lipo Battery for Your Aircraft

To get the best flight time, it is very important to know how to choose the best lipo battery for your drone. If you don’t know about lipo batteries, you can read our lipo battery guide here to learn some key concepts and intentions from the numbers listed, as we will use a lot and discuss in this article.

Like most drone components, batteries are also interrelated with other components. The right battery depends on the size of the drone, the type and number of motors you use. In this article we will discuss how to choose the best battery for your drone before buying it.


To get the longest flight time, you can use a battery with a large capacity, but still, you need to pay attention to how much the maximum takeoff of your drone. For more details about finding out what the maximum weight of your drone takes off, take a look at our guide on how to choose a motor, propeller and ESC for your drone.

Another thing to note is the physical size or dimensions of the battery, because this depends on what type of drone you are using. For this, I think you only need to match a battery of a certain size.


Battery capacity is probably the most important factor, but what is often overlooked is checking the optimal C battery rating for your drone.

Using a discharge rate (C rating) that is too low, it can cause your battery to break quickly, and your drone is below the expected performance. Because the battery cannot release the current fast enough to supply your motor power.

Note: The higher the C battery rating the heavier the weight. if the battery you are using has a C rating that is too high for your drone, it will only carry unnecessary additional loads, which in turn will reduce the flight time of your drone.


Choosing a battery voltage, or cell number is a very important decision that is needed before it is installed to your drone. Higher battery voltage allows your motor to produce more power, but higher voltage batteries weigh more because they contain more cells.

There are no definite rules to follow in terms of battery voltage, but the way we get around and find the best voltage for drones and look through your motorbike’s thrust table and compare its efficiency is the best solution.

We will find that motorcycles are generally more efficient and stronger when using lipo with a higher number of cells (high voltage), but some advantages that efficiency must be paid for by increasing battery load and costs. So, now it depends on how many motors you use and choose what is best for your drone setup.


The amount of battery that you use on a drone is not a problem that makes a difference which eventually raises the pros and cons of using more batteries.

First, using more batteries must use an additional layer of security, as if one battery must fail, you still have another alternative that you can use to quickly land. Also if you have the flexibility to replace one battery if one of them is older than the other.

The charge time can be reduced if you have two chargers, because each can charge at the same time. However using two batteries can be more complicated to mount a wire and buying two batteries can sometimes be more expensive than buying one. So in conclusion, using one or more batteries depends on the drones you use and your own preferences.

About LIPO batteries, what is STORAGE MODE? What is a Discharge Rate? , … and What Is Capacity? And how to calculate it?

Lipo Batteries aka Lithium Polymer, also known as LIPOLY, are powerful batteries that are commonly used on RC hobbies and modeling. Large power is of course accompanied by a large current flow. There are dozens or maybe hundreds of different types of brands, types and specifications of lipo batteries. Lipo batteries are the “spoiled” type, which requires extra attention compared to the types of NiCd, NiMh, Pb etc. … because of the wrong handling, it can have fatal consequences, at least bulging and eventually the cell dies

Storage Mode

This function is only on a programmable balance charger, usually there are 4 buttons, then what is the point for? Its usefulness is when we want to rest the lipo battery for a long time, a month more for example …. just plug into the charger, the settings to storage mode, then the battery will be automatically positioned at the safe voltage in each cell (about 3.8volt in each cell). if it’s too full it will be reduced, otherwise if it’s less … then it will be automatically raised to storage voltage. So it’s safe to store. Don’t try to store lipo batteries only in FULL state without storage and for too long, this is very dangerous … because LIPO is sensitive to temperature changes, without us realizing, LIPO which is filled with electricity in each cell suddenly explodes and causes fires … hmm … there’s been a lot of cases. It is not recommended to also keep lipo for a long time in an empty state. (back to point c above)

Discharge Rate

On the battery pack there is usually a C unit written, for example: 25C – 65C … well, then which one can be counted? On this package, how to read it is: 25C which means unit constant / continuous, meaning that when ESC asks for power at constant speed, then the battery drain will be read by ESC of 25C, while when ESC asks for maximum power (BURST), drain capacity the battery was read by ESC, the maximum from the battery provided, which is equal to 65C. For example, for example the total battery capacity is 6000MaH, then we can calculate it in numbers to find out whether the battery we are using is compatible with the ESC installed or not. The calculation is as below …. (calculate the maximum C battery)

The multiplication factor for RC Car is 0.6, while the multiplication factor for RC Plane and Heli is 1.

Example for RC Car: Battery 6000mah 65C = 6.0aH x 65c x 0.6 = 234A, meaning that your LIPO can serve power requests from ESC which has a maximum amperage of 234A.

For example, for RC Plane: Battery 2200mah 25C = 2.2aH x 25C x 1 = 55A, meaning that your LIPO can serve power requests from ESC with a maximum amperage of 55A


If the discharge rate you provide is far above the ESC and motor demand, then your RC is over powered. The effect can cause overheating on the ESC or motorbike, and if forwarded it can damage both or ESC will automatically continue to CUT OFF VOLTAGE for security.

Likewise, if the discharge rate you provide is MUCH below the ESC and motor demand, then your LIPO will be drained, marked when playing … suddenly the car stops for about 5-10 seconds … then it can walk again. ESC will also automatically do CUT OFF VOLTAGE. This also causes the battery to quickly bloat and shorten life and reduce its ability to store energy / electricity.


Center of gravity or commonly known as CG in aeromodelling aircraft is a matter that must be considered before flying. CG itself is a center of gravity or center, where all the loads seem to be at that point, in other words, when we lift the object on its CG, the object will be balanced.
In aeromodelling aircraft, CG becomes the “fulcrum” and reference point of aircraft movements when doing rotational movements (pitch, roll, yaw) and translation (forward, up, down), so that CG will greatly determine the flight’s attitude, especially longitudinal (pitch) stability. CG can be arranged based on the laying of electronic components in the aircraft, such as shifting the position of the battery and others, batteries that are attached to non-permanent adhesives aim to increase the flexibility of regulating CG.
The following is how to view CG on aeromodelling planes. CG is the point where the location of the hand / finger that we use to lift the plane and plane is balanced as shown in the following figure:

In general, the location of CG from a monoplane trainer with a tail such as cessna, piper cub, spirfire etc. is located at 25-30{2530d6f9f361f4b7115c0b54e4f310320299c4537f29aebb7ff53c6a3142295d} or about a quarter of the chord (rear wing width) measured from the leading edge as shown above. When the CG is located at the position behind that point, or the rear weight, then the plane will tend to be more unstable and easily stalled, this condition is also called tail-heavy. Meanwhile, when the CG is located in the front position, or the front weight, then the plane will tend to swoop forward and difficult to control, this condition is called nose-heavy. Sometimes, tail-heavy conditions are often used for aerobatic aircraft, because an unbalanced plane means it’s easier to maneuver even though it’s difficult to control.
Then, on a flying wing type (without tails), the determination of the location of CG can be done using a calculator that is widely available online, such as at, so we only need to input the size of our plane, and the location of the CG will appear as shown below:

the principle is, CG must be located a little ahead (about 5{2530d6f9f361f4b7115c0b54e4f310320299c4537f29aebb7ff53c6a3142295d} chord, also called static margin) from neutral point (NP). NP itself is the point where the plane will be in a neutral equilibrium condition, that is when the CG is at that point, there is no tendency for the aircraft to stabilize to its initial condition or to an unstable condition.

NP points are affected by wing and tail configuration and airfoil selection and can be calculated using moment equations.
Meanwhile, basically the location of the CG is based on the calculation of the longitudinal equilibrium of the plane, both because of the force and moments of the wings, tail and other components on the aircraft that produce the aerodynamic force as illustrated as follows:

Then, from the picture arrange the moment equation (force times distance) so that it can be seen when the moment = zero at the angle of attack (AOA) zero, and the moment graph towards AOA has neative peculiarity, then the plane is stable Calculations using the above method allow various types of wing, tail and airfoil configurations but it takes time and knowledge of physics and mathematics to determine CG in the above manner so that it is not discussed in detail in this article.

How to Choose an RC Aircraft Propeller

The choice of propeller in aeromodelling aircraft is actually a flexible thing and usually requires trial and error and experience in the field. In this article the general concept will be explained in determining the right propeller for aeromodelling aircraft. It can be said, the selection of propellers is very important in determining the flight performance of the aircraft, even the worst possibility that might occur is damage to aircraft components, this can especially occur in electric aircraft. The most appropriate propeller selection is following the recommendations of the motor / engine provided by maker of these components, but an understanding of the propeller concept is important for aeromodellers.
 The working principle of the propeller is actually identical to the wing, that is by utilizing an airfoil that moves in a rotating manner so as to produce an aerodynamic force (similar to an elevator on a wing) which is called thrust or thrust. The rotating motion of the propeller results in airfoil motion speeds at the tip and base of the propeller being different, therefore the angle of attack (AOA) of the propeller blade from base to end is made smaller, so the force generated is the same (the higher the airfoil speed, the greater the force produced )

Then, two important things that must be known in choosing a propeller are diameter and pitch. Diameter, as the name suggests is the diameter of the propeller when rotating, or it can be said to be the length of the propeller from end to end. Then, pitch is a measure of how much distance the propeller / plane travels will move in the air in one round of propeller in inches. The value of this pitch is only a theoretical number, because in real conditions, there are a lot of factors that affect the distance traveled by each propeller round, such as propeller material, efficiency, air condition and others. The greater the pitch value, the faster the plane will move.

Then the diameter of the propeller generally affects the thrust produced and affects the RPM of the engine, besides that the propeller diameter also greatly affects the noise that is driven by the propeller, sometimes the propeller is more noisy than the engine. The large diameter of the propeller reduces the rotational speed (RPM) of the engine because it requires large power, because of the decrease in RPM, the large diameter propeller is less noisy than a small propeller.
Meanwhile, the pitch and diameter of the propeller are usually written on the propeller in the form of an x pitch diameter. Suppose the propeller with the writing 10 × 8 indicates that the propeller has a 10 inch diamater and an 8 inch pitch.
In aircraft with engine / combustion engines, the following are examples of propeller selection based on charts taken from top flight. In the following example, the A.90 engine is selected so based on the graph, propellers are selected with specifications between 13 × 6 to 15 × 8.

As for electric aircraft, propeller selection is very important. On engine aircraft, the wrong propeller selection only causes the engine to stall and reduce performance, whereas in electric aircraft, the wrong propeller will not make a stall machine, which forces the motor to continue working until perhaps ESC can overheat. Smaller propellers will be safer for electronic components but of course the performance will be less. The best thing to do is to follow the recommendations of the motorbike maker. Theoretically, the selection of propellers can be done using the following equations and graphs:

The issue that is often considered in choosing a propeller is the number of blades. In general, there are two aeromodelling aircraft propeller blades. However, a propeller can be found with three to four blades. In general, the more bars, the propeller will be more inefficient because the turbulent produced is greater. In theory, the most efficient propeller is a propeller with one blade, but the propeller cannot be stable when spinning, unless given a ballast. The propeller with more than two blades is used for scale aircraft so that it gets the perfect scale form, and with more and more blades in general can be chosen smaller diameter and pitch. However, the issue that is most often considered is the ground effect and the height of the propeller to the land which limits the size of the propeller.

Configuration Used to Make an Aircraft

In designing airplanes, unmanned aircraft (UAV), and aeromodelling aircraft, there are quite a variety of aircraft configuration variations such as conventional, tail-boom, tailless, delta and so on.

The number of these variations often makes the dilemma and the debate about which configuration is the best. Therefore, in this article we will discuss a number of airframe configurations, especially those that are a trend among UAVs regarding the advantages and disadvantages of some of these configurations.

a. Tail-aft on Fuselage

This configuration is the most commonly used, so it is not uncommon to be called a conventional configuration. The tail (Empenage) of this configuration in general is in the form of T, Y and V tail.

With a long fuselage, the volume is greater than other configurations, so this configuration is often used for UAVs that require very high endurance to store very much fuel and large sensors.

b. Tail-aft on Booms

The configuration using the tail-boom is quite widely used in UAVs with medium mission distances. The advantage of this configuration is the laying of a driving machine that is close to the center of gravity (CG), making it more stable and easier to set because it is not sensitive to CG.

Then, the empenage location behind the propeller also increases the effectiveness of the control surface (elevator and ruder) so that it is easier to control even at low speeds.

In addition, this configuration allows propellers and machines to be protected during take-off and landing.

c. Canard

This configuration has a horizontal stabilizer far ahead of CG. Unlike the configuration with the tail behind the CG, the horizontal stabilizer in front balances the plane by producing an upward force (lift), so that aerodynamics is more efficient. Then, the wing that is behind also makes stall characteristics better because the stabilizer can be set to stall ahead of the wing.

But because CG is behind, the directional stability (yaw) of this configuration is not good, because giving a vertical stabilizer does not have enough distance to CG so that its effectiveness decreases.

d. Flying wing

This configuration is commonly used by small and medium sized UAVs because of its simplicity, which is structurally advantageous and uses a drive system. In general, the simpler the system, the more reliable it will be.

To achieve longitudinal (pitch) stability, sweep-backs and airfoils that have positive moments are used. In addition, the use of sweep-back also functions to achieve directional stability (yaw).

e. Delta wing

Almost the same as flying wings, which are simple, making this configuration more reliable. In addition, the delta wing shape is also not easily damaged compared to other forms. Even though aerodynamically, the delta shape is less profitable because it produces large induced drag.

This delta shape is usually used also to store parachutes because of the wide cross section of its wings.