Topic
Flight questions for kids
Here are 210 questions about flight from 20 A Million Whys books, each with a short video answer. Book 23, The Flight Expedition is all about flight, and the rest come from other books in the series. Tap any question to watch the video and read the answer.
From Book 23: The Flight Expedition (150)
What Are the Four Forces of Flight?
Every flying thing is balanced by four forces. Lift, weight, thrust, and drag all push and pull at once.
What Is Lift, and Where Does It Come From?
Lift is the upward push on a wing. Without it, nothing heavier than air could fly.
How Does the Shape of a Wing Help It Climb?
A wing is not just a flat board. Its special shape helps it climb into the sky.
What Is Thrust, and How Do Planes Get It?
Thrust is the force that moves a plane forward. Without it, a plane would just sit on the runway.
What Is Drag, the Force That Slows Things Down?
Drag is the force that slows things down. You feel it when you push against a strong wind.
How Does Weight Pull on Every Flyer?
Weight is Earth's gravity pulling on everything. Even things that fly must deal with it.
What Is the Angle of Attack?
A wing can be tilted up a little compared with the air. That tilt is called the angle of attack.
What Is a Stall, and How Do Pilots Handle It?
A stall sounds scary. But it has nothing to do with the engine stopping.
Why Do Planes Need to Go Fast Before They Can Take Off?
A plane cannot just jump into the sky. It has to roll down the runway first.
Why Do Airplanes Take Off Facing Into the Wind?
Pilots love taking off and landing into the wind. It might seem backward.
Does a Wing Really Push Air Downward to Go Up?
Does a wing really push air downward to go up? Yes, it does!
How Are Lift and Weight Balanced in Level Flight?
When a plane flies straight and level, all the forces balance. Lift matches weight, and thrust matches drag.
What Happens to the Four Forces During Takeoff, Cruising, and Landing?
A flight has three big parts. Take-off, cruising, and landing.
How Do Ailerons Help a Plane Roll and Turn?
A plane can roll to the left or right in the sky. Little flaps on the wings make that happen.
What Do the Rudder and Elevator at the Tail Do?
The tail of a plane is not just for looks. It has two important controls.
What Are Pitch, Roll, and Yaw?
A plane can turn in three different ways. They have funny names.
Why Does a Plane Tilt to the Side When It Turns?
Have you noticed a plane tilts when it turns? It leans into the curve like a bike rider.
Why Do Some Planes Have Curved-Up Wingtips?
Look closely at some airliners' wingtips. They curve up into little fins.
Why Do Big, Heavy Flyers Need Big Wings?
Heavy flyers need big wings. A swan has much larger wings than a sparrow.
Can a Plane Fly Upside Down?
Can a plane fly upside down? You might think it could not.
Why Do Jets Cruise So High Up Where the Air Is Thin?
Jets cruise way up high, where the air is thin. They fly higher than most clouds.
How Do Wind Tunnels Help Engineers Test Wings?
How do engineers test new wings before building a plane? They use a giant tube with a fan.
Why Do Airplane Wings Bend Upward in Flight?
In flight, an airplane's wings bend upward. It might look scary, but it is by design.
What Did the Wright Brothers Discover About Flight?
Orville and Wilbur Wright were bicycle makers. They had a big dream about flying.
How Do the Four Forces Explain a Bird, a Plane, and a Kite?
A bird, a plane, and a kite all stay in the air. They look so different.
How Do Feathers Turn a Bird's Wing Into a Flying Machine?
A bird's wing is covered in feathers. They turn a wing into a flying machine.
Why Do Some Birds Flap Constantly While Others Soar?
Some birds flap and flap. Others glide for hours on still wings.
How Do Light, Hollow Bones Help Birds Fly?
Birds need to be light to fly. Many of their bones are hollow!
How Do Birds Land So Gracefully?
Birds land on a tiny branch with perfect balance. It looks so easy.
What Do a Bird's Tail Feathers Do in the Air?
A bird's tail is like a steering wheel with feathers. It acts like a rudder and an elevator at once.
How Does a Heavy Swan Get Off the Water and Into the Air?
A swan is one of the heaviest flying birds. Getting into the air is a big job for it.
What Is a Thermal, and How Do Hawks Ride One?
Hawks and vultures circle high in the sky without flapping. They are riding invisible elevators.
How Can an Albatross Cross an Ocean with Hardly Any Flapping?
An albatross can cross an entire ocean. It hardly flaps its wings at all.
Why Can Ostriches and Penguins Not Fly?
Ostriches and penguins are birds. But neither one can fly.
How Can an Insect Beat Its Wings Hundreds of Times Each Second?
A honeybee beats its wings hundreds of times each second. How can any muscle move so fast?
How Does an Insect's Chest Work Like a Wing-Wiggling Box?
Here is a surprise about insect wings. The muscles that move them are not in the wings.
How Do Bumblebees Fly When People Once Said They Could Not?
There is an old story about bumblebees. It says scientists once decided they could not fly.
How Is a Bat's Wing Different From a Bird's Wing?
A bat's wing is very different from a bird's wing. It has no feathers at all.
What Is the Difference Between Flying and Gliding for an Animal?
Some animals fly and some animals glide. They are not the same thing.
Can Snakes and Frogs Glide Through the Air?
Snakes and frogs can glide through the air! It sounds like a tall tale.
How Do Dandelion Seeds Sail on a Breath of Wind?
A dandelion seed sails away on a puff of wind. It looks like a tiny parachute.
How Do Baby Birds Learn to Fly?
Baby birds are born without the ability to fly. They have to learn.
Can Any Bird Sleep While Flying?
Could a bird sleep while it is flying? It sounds impossible.
How Does a Feather Stay Light, Strong, and Smooth?
A feather is light, strong, and smooth all at once. How does it do that?
How Far Can a Bird Fly Without Stopping?
Which bird can fly the farthest without stopping? The record is almost unbelievable.
How Do Birds Change the Shape of Their Wings?
A bird can change the shape of its wings in the air. It can bend, fold, and fan them.
Why Do Some Birds Have Long, Pointed Wings and Others Short, Round Ones?
Some birds have long, pointed wings. Others have short, round ones.
How Do Baby Spiders Fly on Silk Threads?
Baby spiders can fly! They do it without any wings.
Why Can't People Fly by Flapping Wings Tied to Their Arms?
Why can't people flap wings tied to their arms and fly? Birds do it all the time.
What Can Engineers Learn From Flying Animals?
Flying animals have had millions of years to practice. Engineers watch and learn from them.
How Does a Jet Engine Work?
A jet engine follows four simple steps. Suck, squeeze, bang, blow!
What Does the Huge Fan at the Front of a Jet Engine Do?
The front of a jet engine has a huge fan. It looks like a giant propeller in a tube.
What Do All the Dials in a Cockpit Tell the Pilots?
A cockpit is full of dials and screens. Each one gives pilots important information.
How Does an Altimeter Know How High a Plane Is?
How does an airplane know how high it is? It feels the air!
How Does a Plane Know How Fast the Air Is Flowing Past It?
How does a plane know how fast air is flowing past it? It uses a thin tube sticking out the front.
What Is an Artificial Horizon, and Why Do Pilots Need It?
In clouds or at night, a pilot cannot see the real horizon. It is easy to lose track of which way is up.
What Does an Autopilot Do?
An autopilot is a computer that can fly a plane along a set path. It does not replace the pilots.
Why Do Planes Fold Their Wheels Up After Takeoff?
After take-off, planes fold their wheels up. They disappear into the body of the plane.
Why Is the "Black Box" on an Airplane Actually Orange?
Airplanes have a special recorder called a black box. Strangely, it is not black at all.
What Makes the White Trails That Jets Leave Behind?
Jets sometimes leave long white trails in the sky. They look like clouds made by a plane.
Why Do Airplane Windows Have Round Corners and a Tiny Hole?
Airplane windows have round corners. They also have a tiny hole.
How Does a Plane Keep the Air Comfortable at 35,000 Feet?
Outside a jet at 35,000 feet, the air is thin and freezing. Inside, passengers breathe easily.
What Is Turbulence, and Why Does It Happen?
Sometimes a plane shakes in the sky. The seat belt light goes on.
Why Do Flight Attendants Ask for Tray Tables and Seats to Be Upright?
Flight attendants ask everyone to put tray tables away and seats upright. It happens at takeoff and landing.
Why Are Most Airplanes Painted White?
Look at most airplanes. They are white!
What Are the Panels That Pop Up on the Wings After Landing?
After landing, panels pop up on the wings. They look like little flaps standing up.
How Do Airplanes Slow Down So Fast After They Land?
A landing plane rushes down the runway. Then it slows down quickly.
What Is an Airplane Made Of?
An airplane must be strong, but also light. What do engineers use?
How Many Parts Does a Jumbo Jet Have?
A jumbo jet is a giant puzzle. How many pieces does it have?
How Do Planes Get Cleared of Ice in Winter?
In winter, ice can form on a plane's wings. That is dangerous.
What Happens When Lightning Strikes an Airplane?
Lightning can strike an airplane. That sounds scary!
Where Does an Airplane Carry Its Fuel?
A big jet burns lots of fuel. Where does it keep it all?
Where Do Suitcases and Cargo Ride on an Airplane?
Where do suitcases go on a plane? They ride below your feet!
How Can a Plane Land Safely in Thick Fog?
Fog can hide the runway completely. Can a plane still land?
How Can a Floatplane Take Off From a Lake?
Some airplanes take off from a lake. They do not have wheels!
What Makes a Helium Balloon Float Up While a Regular Balloon Sinks?
A helium balloon floats up. A balloon you blow up yourself sinks.
Why Does Helium Change the Sound of a Voice?
Helium makes the voice squeaky. It sounds funny!
What Do the Burner and the Top Vent Do During a Balloon Ride?
A hot air balloon has a burner and a vent. One makes it go up.
How Can a Balloonist Pick a Direction Without a Steering Wheel?
A balloon has no steering wheel. How does the pilot choose where to go?
When Did People First Fly in a Balloon?
Long ago, people only dreamed of flying. Then some clever brothers built a balloon.
What Makes a Blimp Different From a Drifting Balloon?
A balloon drifts with the wind. A blimp can go where the pilot wants.
Why Do Airships Use Helium Instead of Hydrogen?
Hydrogen is lighter than helium. So why do airships use helium?
Why Does a Weather Balloon Swell as It Rises, and Then Pop?
A weather balloon starts small. As it rises, it swells.
How Do the Spinning Blades of a Helicopter Make Lift?
A helicopter has spinning blades. They do not push it like a fan.
Why Does a Helicopter Have a Little Propeller on Its Tail?
Look at the tail of a helicopter. There is a little propeller!
How Does a Helicopter Lean to Fly Forward?
A helicopter leans to go forward. The pilot tilts the whole spinning rotor.
Why Can a Helicopter Fly Sideways and Backward?
A plane cannot fly backward. But a helicopter can!
What Happens If a Helicopter's Engine Stops?
What if a helicopter's engine stops? Pilots train for this.
What Jobs Do Helicopters Do?
Helicopters can land almost anywhere. That makes them great helpers.
How Do Paragliders Stay Up in the Air?
A paraglider has no engine. Just a soft wing and the air.
How Can a Sailplane Glide for Hundreds of Miles?
A sailplane has no engine. Yet it can fly hundreds of miles!
What Is a Glide Ratio?
How far can a plane glide? There is a number that tells you.
How Does a Boomerang Come Back?
Throw a boomerang and it comes back! That seems like magic.
What Is the Difference Between Lighter-Than-Air and Heavier-Than-Air Flight?
Some things fly because they are lighter than air. Others are heavier but still fly.
What Are Electric Air Taxis?
Imagine a quiet flying taxi over a city. Some are being tested right now.
Can a Plane Fly Using Only Sunshine?
Can a plane fly with no fuel? Yes!
How Do Stunt Pilots Do Loops and Rolls?
At airshows, planes loop and roll. Those are stunt planes.
How Do Firefighting Planes Scoop Up Water From a Lake?
Some planes fight forest fires. They scoop up water without landing.
Can a Plane Fly on Human Leg Power?
Could you fly by pedaling? Someone really did it!
How Do Bush Planes Land on Short, Bumpy Strips?
Some places have no airports. Bush planes can land on gravel, snow, or water.
How Do People Learn to Become Pilots?
Every pilot started as a beginner. They learned step by step.
What Is a Flight Simulator?
Pilots practice in a machine that never leaves the ground. It feels like flying!
What Do Pilots Check Before They Take Off?
Pilots do not just jump in and go. They check lots of things first.
Why Do Airports Scan Bags with X-Rays?
At the airport, your bag rides through a scanner. It sees inside without opening it!
Why Do Pilots Say "Alpha, Bravo, Charlie" When They Talk on the Radio?
Pilots say funny words like Alpha, Bravo, and Charlie. They are not just being silly.
What Does an Air Traffic Controller Do?
The sky is busy with planes. Someone has to keep them apart.
Why Does an Airport Have a Tall Control Tower?
Every big airport has a tall tower. It has big windows at the top.
How Do Planes Stay Safely Apart in a Crowded Sky?
Thousands of planes fly each day. How do they never bump?
How Does Radar See Airplanes?
Radar can see a plane far away. It does not use eyes.
How Do Pilots Find Their Way Across an Ocean?
Over an ocean there are no signs. Pilots cannot see any roads.
Why Do Flight Paths Look Curved on a Flat Map?
Earth is round like a ball. The shortest path is a great circle.
Why Do Runways Have Numbers?
Every runway has a number. That number is a direction clue.
What Do the Lines and Lights on a Runway Mean?
Runways have lines and lights. They work like road signs for pilots.
Why Do Airports Have So Many Different Kinds of Vehicles?
Airports are busy places. Many special vehicles help each plane.
Why Does a Tug Push an Airplane Away From the Gate?
A jet at the gate faces the building. It cannot safely back up alone.
How Long Does It Take to Get a Plane Ready Between Flights?
Planes do not rest for long. A turnaround can take under an hour.
Why Does a Flight From Toronto to London Take Less Time than the Trip Back?
Winds high above Earth are super fast. Going east can feel like a push.
What Is Jet Lag?
Your body has a clock inside. Flying far can confuse that clock.
How Far Can You See From a Plane Window?
A plane window view feels huge. The ground shrinks into tiny shapes.
How Many Planes Are in the Sky at Once?
The sky looks empty from the ground. But many planes share the air at once.
How Do Airports Keep Birds Away From Runways?
Birds and planes should not share a runway. Airports use many gentle ways to keep birds away.
Why Does a Puff of Smoke Appear When a Plane Lands?
When a plane lands, you may see a puff of smoke. The wheels were not spinning yet.
What Are Some of the Biggest Airplanes Ever Built?
Some airplanes are truly huge. One carries hundreds of people on two decks.
How Did Concorde Cross the Atlantic in About Three Hours?
Concorde crossed the Atlantic in about three hours. It flew faster than the speed of sound.
How Are New Airplanes Tested Before They Carry People?
New airplanes face years of tough tests. Engineers push them harder than real flights will.
Which Paper Plane Designs Fly the Farthest, and Why?
Paper planes come in two main styles. Darts are fast and pointed.
How Do You Test a Paper Plane Fairly?
A fair test changes only one thing. Everything else stays the same.
What Happens When You Put a Paper Clip on the Tail of a Plane?
Balance decides how a paper plane glides. A clip on the nose can steady it.
Why Do Paper Planes Fly Steadier When Their Wings Tilt Up Into a Shallow V?
Wings tilted up in a shallow V help a plane stay steady. If it rolls, the low wing gets more lift.
How Can Small Bends in the Back of the Wings Stop a Plane From Diving?
Tiny bends at the back of the wings can fix a dive. They work like elevators on a real airplane.
Why Does a Paper Helicopter Spin as It Falls?
A paper helicopter falls and spins. Its flaps face opposite ways.
Do Bigger Wings Always Fly Better?
Bigger wings make more lift. But they also add weight and drag.
What Do the Tail and String of a Kite Do?
A kite has a tail and a string. They look simple, but they matter.
Where Is It Safe to Fly a Kite?
Kites need lots of open sky. Some places are dangerous.
What Makes a Diamond Kite Fly Well?
A diamond kite looks simple. Two sticks and light cover.
What Is Special About a Box Kite?
A box kite looks like boxes in the sky. It has more sides than a flat kite.
How Do Stunt Kites Use Two Strings to Steer?
Some kites have two strings. One in each hand.
How Can a Twisted Rubber Band Power a Tiny Airplane?
A tiny plane has no battery. Just a twisted rubber band.
How Can You Tell Which Way the Wind Is Blowing?
Wind can be hard to see. But you can still find its path.
Why Does a Feather Fall More Slowly than a Coin?
Drop a feather and a coin. The feather drifts, the coin zooms.
Why Do Phones Need Airplane Mode on a Plane?
Phones talk to towers with radio signals. On a plane, those signals can cause trouble.
Why Must Everyone Stay Far From a Spinning Propeller or a Running Jet Engine?
Propellers and jet engines are very powerful. They can be dangerous up close.
Why Is Flying One of the Safest Ways to Travel?
Flying is one of the safest ways to travel. That is no accident.
What Jobs Help Planes Fly Besides Pilots?
Pilots fly the plane. But they never work alone.
How Do Mechanics Keep Planes in Top Shape?
Planes fly many hours every day. They need lots of care.
Can a Balloon on a String Show How Thrust Works?
A fan blows air one way. Put it on a toy cart.
How Can You Graph the Results of Your Flight Tests?
You tested your paper planes. Now you have lots of numbers.
Why Can a Ring-Shaped Straw Glider Fly?
A glider made from a straw and two paper rings? It does not look like a plane.
Which Sky Puzzles Are Engineers Still Working On?
Planes are amazing already. But engineers want them even better.
What Should Every Young Pilot-In-Training Remember About Flight?
Birds, planes, helicopters, and balloons all fly. They follow the same rules.
From Book 1: The Great Expedition (3)
Why Do Your Ears Pop on a Plane or in a Car?
That funny pop in your ears is all about air pressure! When you go up high in a plane, or change height quickly on a hilly car ride, the air pressure outside changes.
Why Do Butterfly Wings Have Colors? Paint vs. Tiny Mirrors!
Butterfly colors come from two tricks. Some color is pigment, which is like nature's paint that soaks into things.
Why Do Airplanes Fly? Lift, Thrust and Smart Wings!
Huge airplanes stay in the sky thanks to lift, thrust and smartly shaped wings. As a wing moves forward, its shape turns the air downward, and the air pushes the wing up, which is called lift.
From Book 3: The Built Expedition (10)
Why Do Airplanes Stay in the Sky?
A plane wing is curved on top and flatter underneath. When air rushes over that shape, the wing gets an upward push called lift.
Why Do Paper Airplanes Fly?
A paper plane is really a tiny wing that you throw. The paper is both the body and the wing, and your throw gives it speed.
Why Do Helicopters Hover?
Helicopter blades are wings. Spinning blades are long, thin wings, and as they whirl, they make lift.
Why Do Hot Air Balloons Go Up?
Heat makes the air molecules spread out. So the same bag of hot air weighs less than the cool air around it.
Why Do Planes Have Flaps?
A flap is a hinged panel on the back of the wing. When the pilot drops it, the wing becomes bigger and more curved.
Why Do Airplanes Have Propellers?
A propeller is a set of twisted blades. When they spin, they shove air backward, and the plane is pulled or pushed forward.
Why Do Parachutes Work?
A parachute is a giant air brake. It makes a wide surface that slams into many air molecules, so the fall slows down to a safe speed.
Why Do Gliders Fly with No Engine?
A glider is a plane with no engine. It trades height for forward speed, then finds rising air to climb again.
Why Does a Frisbee Fly?
A flying disc is a spinning wing. Air moves faster over the curved top than under the rim, and that creates lift.
Why Does a Kite Need Wind?
A kite is like a wing on a string. Moving air hits its tilted face and slides over the top.
From Book 4: The Wild Expedition (8)
Why Do Flies Rub Their Feet?
A fly tastes with its feet. After a messy landing, rubbing its feet scrapes off dust and sticky food, so the taste sensors work again.
Why Do Moths Fly to Lights?
Many night moths steer by a faraway light, like the moon. A porch bulb is like a fake moon that sits far too close.
Why Do Flies Have Compound Eyes?
A compound eye is a bundle of tiny lenses! Together, they make a wide, fast picture.
Why Do Owls Fly So Quietly?
Silence is a hunting tool! An owl that whispers through the air can hear a mouse.
Why Do Bats Fly at Night?
Night is an open shift for hunters! Many bats hunt moths and mosquitoes after the birds that hunt by sight have gone to roost.
Why Do Geese Fly in a V?
A V is teamwork in the sky! Each bird rides a little lift from the swirl at the wingtip of the bird ahead.
Why Do Owls Fly So Quietly? Think Like the Mouse
An owl hunts mostly by listening, and a mouse has sharp ears too. If the owl's wings were loud, the mouse would hear a warning and run away, so owls are built to hush the air.
Why Do Moths Fly at Lights?
Many moths steer by a distant light, like the moon. Keeping it at a steady angle works like a night compass.
From Book 5: The Time Expedition (1)
From Book 6: The Ocean Expedition (4)
Why Do Flying Fish Jump?
A flying fish shoots out of the water and spreads its long, stiff fins like wings. It does not flap like a bird.
Why Does a Manta Look Like It Is Flying?
A manta ray flaps its huge, pointed fins up and down, and it looks like a bird in flight. But a manta is swimming, not flying.
Why Do Big Ships Have Such Small-Looking Propellers?
A big ship's propeller looks small next to its huge hull. But up close, its blades can be taller than a person!
Why Do Harbors Need Pilots?
A harbor pilot is a local expert who steps aboard a big ship to guide it through a busy port. The captain knows the ship.
From Book 7: The Weather Expedition (4)
Why Can Airplanes Fly Through Clouds?
A cloud looks like a solid pillow, but it is not solid at all. It is mostly air, with tiny droplets spaced far apart.
Why Do Jet Streams Race High Above Us?
Jet streams are fast rivers of wind high up in the sky. They blow about 9 to 12 kilometers above the ground, which is where airplanes cruise.
Why Do Airplanes Care About Wind?
Airplanes fly through moving air, so wind matters a lot to them. A tailwind pushes a plane from behind and speeds the trip.
Why Do Pilots and Sailors Need Forecasts?
Airplanes and ships travel for hours across big open spaces, and weather changes along the way. Pilots and sailors need to know about wind, waves, clouds, and storms before they leave.
From Book 8: The Space Expedition (1)
From Book 9: The Food Expedition (2)
Why Does Food Taste Blander on an Airplane?
Food tastes blander on an airplane because the dry, low-pressure cabin air dulls your senses! It dulls your sense of smell and makes taste buds less sensitive.
Why Truck, Ship, and Fly Food Around the World?
We truck, ship, and fly food around the world because climate and seasons limit what grows nearby! Bananas need warm weather, while apples need cool winters.
From Book 11: The Animal Expedition (1)
From Book 12: The Volcano Expedition (1)
From Book 13: The Light Expedition (2)
Why Must You Never Shine a Laser Pointer at Anyone's Eyes, a Plane, or an Animal?
A laser pointer packs lots of light into a tiny spot, so it is a tool and not a toy! Never shine one at eyes, planes, or animals.
Why Do Airplanes and Boats Have Red and Green Lights?
Planes and boats have a red light on the left side and a green light on the right side! In the dark, the colors tell you which way the vehicle is going.
From Book 14: The Sound Expedition (3)
Why Can You Hear a Mosquito's Wings but Not a Slowly Flapping Bird's?
You hear a mosquito's wings because they beat hundreds of times each second! That is fast enough to make a tone your ears can hear.
Why Does a Jet Flying Faster than Sound Make a Boom?
A jet flying faster than sound makes a boom because its sound waves pile up into a shock wave! When that wave passes you, your ears hear a sudden loud boom.
Why Does a Plane Seem to Be in a Different Place than Its Sound?
A plane seems to be in a different place than its sound because sound is slower than the plane! What you hear left the plane a while ago, even though the plane looks close.
From Book 15: The Robot Expedition (6)
Why Do Two of a Drone's Propellers Spin One Way and Two the Other?
Two propellers spin one way and two spin the other so the drone stays pointing straight! Every spinning propeller gives the drone body a small twist in the opposite direction.
Why Does a Drone Tilt to Fly Forward?
A drone tilts to fly forward because a tilt turns its up-and-down push into a forward push! The rotors push air backward as well as down.
Why Can't Most Drones Fly for Very Long?
Most drones can't fly for very long because holding themselves up takes a lot of power! A drone must push air downward all the time, or it falls.
Why Do Some Drones Have Little Cages Around the Propellers?
Some drones have little cages around their propellers to keep the spinning blades and everything nearby safe! If the drone bumps into something, the cage takes the hit.
Why Must Drones Stay Away From Airports and Crowds?
Drones must stay away from airports and crowds because flying safely means keeping everyone safe! A drone that falls or crashes could hurt someone or damage things.
Why Can a Drone Hover but an Airplane Can't?
A drone can hover because its propellers are tiny spinning wings, but an airplane's wings must keep moving forward! Wings make lift only when air flows past them.
From Book 17: The Rainforest Expedition (4)
What Are the Flying Rivers of the Amazon?
Flying rivers are streams of water vapor that flow through the air above the rainforest, carried by winds. They bring moisture from the Atlantic Ocean across the forest, and the trees add more along the way.
Why Do Some Rainforest Seeds Spin Like Helicopters?
Some rainforest seeds have a wing that makes them spin like tiny helicopters! Tall trees, such as dipterocarps in Southeast Asia, use this trick.
How Do Glasswing Butterflies Get See-Through Wings?
Glasswing butterflies have see-through wings because of tiny structures, not color! Their clear wings have almost no colored scales.
What Tiny Flies Pollinate Chocolate Trees?
Chocolate trees are pollinated by tiny flies called midges, not by bees! Without these little insects, there would be far fewer cocoa beans.
From Book 18: The Polar Expedition (3)
Why Does the Arctic Tern Fly From Pole to Pole?
The Arctic tern flies from pole to pole to enjoy two summers every year! It nests in the Arctic summer, then flies south to the Antarctic summer.
How Do Planes Land on Snow and Ice?
Planes land on snow and ice by using skis instead of wheels! Skis spread the plane's weight over a wide area, so it glides on top.
How Do Robots and Flying Machines Help Scientists on the Ice?
Robots and flying machines go where it is too cold or risky for people! They send back pictures and measurements to the scientists.
From Book 19: The River Expedition (1)
From Book 20: The Mountain Expedition (4)
How Can Bar-Headed Geese Fly Over the Himalayas?
Bar-headed geese fly over the Himalayas, the highest mountains on Earth, with big lungs and super blood! They travel between India and Central Asia.
Why Do Flies Matter So Much to High-Mountain Flowers?
Flies matter so much to high-mountain flowers because they are the main visitors! At high altitudes, there are fewer bees, but there are plenty of flies.
Why Does a Ball Fly Farther at High Altitude?
A ball flies farther at high altitude because the air is thinner! Air pushes back on anything that moves through it.
Why Do Airplanes Need Longer Runways at High Airports?
Airplanes need longer runways at high airports because the air is thin! Planes need to reach a certain speed to lift off.
