Lesson 4: Let’s get practical: Physics, Batteries, and Maintenance 

Welcome! Today, we’ll be learning some practical knowledge about how our drones actually work.

First, let’s talk about the ways that drones can move in the air. 

There are three basic ways that a drone can move! They’re called roll, pitch, and yaw.  

Roll 

Roll is when a drone tilts to the left or right. This move helps you change direction. To imagine this, stick out your arms like airplane wings and then tip them up and down. It’s like when you lean your bike to turn a corner!

Pitch

Pitch is when a drone points its nose (front) up or down. This move helps you change your altitude, or the height you’re flying at. To imagine pitch, nod your head up and down, as if you’re saying “yes”. It’s like a seesaw moving up and down. 

Yaw

And finally, yaw is when a drone turns left or right while staying level. This move helps you change direction without tipping. Yee-haw! To imagine this, turn from side to side while keeping your head and body straight. It’s like when a top is spinning in one spot

• Roll: When the drone tilts to the left or right. 

• Pitch: When the drone's nose points up or down. 

• Yaw: When the drone turns left or right while staying level. 

Ah, even more flight lingo! What does level mean? Level means flying evenly and parallel to the ground! Did you know that drone controllers look a lot like video game controllers? And, once you read your manual, you can learn how to do cool tricks with your drone’s controller – just like this!  Understanding and mastering these moves will give you more precise control over your drone’s flight – and the confidence to fly it! This helps with things like navigating tricky terrain, getting the coolest camera angles, and avoiding collisions!

Aerodynamics

Great work! Next up, let’s learn about another thing that’s super important to know: the four principles of aerodynamics! This sounds fancy! But all it means is understanding how objects (like drones!) move through the air. Exactly! Something to keep in mind is that “aero” means “air” and “dynamics” means “movement”. 

The principles of aerodynamics

Aerodynamics is the study of how air moves around things, like airplanes and cars. It helps us understand how objects can fly, move faster, and be more efficient. By learning about aerodynamics, we can design things that cut through the air smoothly, like a bird gliding in the sky or a race car speeding on a track.

First, let’s imagine our drone is flying in a straight, horizontal line and it’s not speeding up or slowing down. That’s called “straight-and-level” (straight)  unaccelerated (consistent speed) flight”. And all of the time, there are four forces that are acting on your drone when it flies – and any other object, too! 

Thrust

The first force is called thrust. Thrust is what pushes your drone forward. Think of it as the drone's engine power. The motors and propellers create this thrust, kind of like how a car's engine moves it forward. Without thrust, your drone wouldn't go anywhere!

Drag

Next, we have drag. Drag is the force that tries to slow your drone down. It's a ‘drag’ to be around! Drag is caused by air pushing against the drone as it moves, similar to how you feel the wind resistance when you stick your hand out of a moving car window. Engineers work hard to design drones that cut through the air more efficiently to minimize drag. You might also see drag referred to as “friction”! That makes sense, too. 

Weight

Now, let's talk about weight. Weight is the force pulling the drone down toward the Earth, just like how gravity makes things fall. The weight of your drone depends on how heavy it is, including everything it's carrying. The heavier the drone, the more weight it has pulling down on it. And the more weight it has pulling down on it, the more likely it is to fall from the sky. 

Lift

Finally, we have lift. Lift is the force that pushes the drone up into the air, counteracting the weight. Drones create lift with their wings or rotors. The air flows over and under the drone’s wings, creating an upward force that keeps the drone in the air. When a drone is flying in straight-and-level, unaccelerated flight, everything is in perfect balance, also known as equilibrium. Lift equals weight, and thrust equals drag. This balance keeps the drone flying smoothly. Isn't that amazing?

Recap

So, to recap, the four forces acting on your drone are thrust, drag, weight, and lift. Thrust pushes it forward, drag tries to slow it down, weight pulls it down, and lift pushes it up.

Let’s talk about LiPo Batteries!

Many of the types of drones you’ll be flying use a special type of battery called LiPo batteries. LiPO batteries need to be treated with care! Every drone pilot needs to know how to take care of them to keep their drones flying safer and longer. But, what exactly are LiPo batteries? LiPo stands for lithium-ion polymer. These batteries are powerful – and rechargeable!

LiPo batteries, or Lithium Polymer batteries, are a type of rechargeable battery that is lightweight and can store a lot of energy. They are used in many gadgets like drones, remote-controlled cars, and smartphones because they provide strong and consistent power. Unlike regular batteries, LiPo batteries can be shaped into different sizes, making them perfect for all kinds of devices.

Now, let’s talk about how long these batteries last. 

With good care, a LiPo battery can last for 200-300 cycles. A cycle is one complete charge and discharge of the battery. But if you don't take care of them, they might only last for about 50 cycles! That’s a big difference!

Now, LiPO batteries are hard to take care of! Sometimes, they can even swell up or catch on fire! So, let’s talk about what causes this to happen! 

1. First, if you charge your LiPO batteries for too long, they can get damaged, and will overheat and swell up. So don’t overcharge them! 

2. Second, if you use LiPO Batteries until they are completely empty (over-discharged), it’s a lot harder for them to recharge properly. 

3. Third, physical damage, like dropping them, can also harm LiPo batteries and even cause them to catch fire! 

4. And finally, did you know the weather plays an important role in how well batteries do?  Extreme temperatures, both hot and cold, can damage the batteries. High heat can cause them to overheat and swell. And very cold temperatures can reduce their performance and capacity. Additionally, exposure to moisture from rain or humidity can lead to short circuits or corrosion, making the batteries unsafe to use.

That’s why it’s a good idea to keep track of your battery cycles in your drone maintenance logs. This helps you know when it's time to replace them.

Logging

Wait, pilots have to keep journals of more things? 

You should log your drone flights and all your maintenance work. Keeping track of this important stuff in your drone journal helps ensure everything is running smoothly. Safety is super important when it comes to LiPo batteries. Here are some tips to keep you and your drone safe! 

How to take care of your LiPO Batteries  

• Always use a safety bag or fire-proof container when charging, discharging, or storing your batteries. 

• If you’re traveling with batteries, avoid putting LiPo batteries in checked baggage. Instead, carry them with you and store them in a cool, dry place.

• If your battery is damaged or swollen, dispose of it properly. Check your local laws – you might have to take them to a recycling facility. 

• Always avoid buying used or unknown-brand batteries. It’s not worth it! 

• Extreme temperatures can make your battery performance worse. Keep them away from too much heat or cold.

• Charge them properly! Use a good LiPo battery charger. Never overcharge or over-discharge your battery and never leave them charging unattended.

Taking care of your LiPo batteries is key to getting the most out of them! Remember to use safety bags, avoid extreme temperatures, and always check for damage. And don’t forget to track those battery cycles!

Nice work! The last lesson in this chapter is about something that’s also super important – drone maintenance!  

Maintenance

Think about it like this: imagine you're pulling your bike out of the garage for your first ride of the summer. 

What do you do? 

You check the tires, brakes, and chain to make sure everything’s in order, right?

It’s the same with your drone! You need to check that everything is working properly before you start flying.

As a certified remote pilot, it’s your job to keep your drone in safe working condition. Right! So, that means checking your drone’s condition before every flight to make sure everything’s working as it should.

So… how do you know when to perform maintenance on your drone?

Usually, your drone manufacturer will give you a maintenance schedule to follow. But what if they don’t? No worries! You can create your own maintenance schedule. It’s helpful to base it on a maintenance manual that already exists, like from a drone that’s similar to yours.

Creating a scheduled maintenance plan might sound complicated, but it really comes down to two things. 

Record any repairs, changes, or replacements you do during regular flights.  Use a written or online maintenance log for each part of your drone. Keep track of how long each part has been in use. This helps you know when it might be time to check or replace a part.

And finally, here are some really practical maintenance tips. 

3 Drone Pro Maintenance Tips   

• Always do a thorough check of your drone before each flight. Look over all parts to make sure nothing is damaged or out of place.

• Stick to your maintenance schedule to ensure everything is regularly checked and maintained.

• Log all maintenance activities like repairs, modifications, overhauls, and replacements. This keeps track of your drone’s condition and history.

Fantastic Work today! 

Great work! I see you’re all a few steps closer to becoming a certified drone pilot.