Flying Machine Book: Build and Launch 35 Rockets, Gliders, Helicopters, Boomerangs, and More
1 Flight School The ability to fly has amazed people since time began The earliest humans watched birds soaring in the sky and dreamed of joining them Kites were probably humankind’s first attempt to reach the skies The Chinese first started flying kites around 400 BC for ceremonies and just for fun Leonardo da Vinci was the first person known to seriously study flight His drawings described his theories on bird flight Da Vinci even drew pictures of imaginary flyers that would allow a person to fly under his or her own power Although none were built for over 400 years his designs inspired the invention of the helicopter In the late 1700s hot air gave human-powered flight a lift People discovered that hot air rises so a bag filled with hot air will float This led to the invention of the hot air bal loon Hot air balloons soared over Europe in the 1780s giving people the opportunity to realize their dreams of flying through the air Around 1800 Englishman George Cayley took flying in a new direction when he discovered the modern airfoil Cayley often called the Father of Aviation because of his studies is acknowledged as the first person to realize that the battling forces governing flight were lift thrust drag and weight He also built the first glider capable of holding a person and that first flyer was a 10-year-old boy Cayley also experimented with rudders and flaps just like you will on the flyers in this book 1
2 K O O B E N I H C A M G N I Y L F E H T Of course the Wright brothers pioneered powered flight but Cayley’s work is more closely related to the flying machines you will be building Each chapter in this book focuses on one type of flyer helicopters rockets boomer angs and different types of gliders Not all the flyers are easy to make and many take practice to perfect But with a little patience your flyer can reach the sky The Bernoulli Principle Daniel Bernoulli’s dad a brilliant mathematician never wanted his son to study math Instead he wanted Daniel to study medicine because it paid better Daniel did go into medicine but never forgot his love of math As a math professor in his 20s he discovered a principle that combined his interests in math science and medicine and it made him both famous and rich At the time of his discovery Bernoulli was working with blood He wanted to know about the relationship between blood pressure inside an artery and the speed of the blood through the artery He soon realized that if he punctured a tube carrying a fluid with a thin pipe the fluid would go up the pipe And more interestingly how far it rose due to pressure was related to the speed of the fluid past the end of the pipe For the next 150 years in Europe physicians would measure blood pressure by piercing a patient’s artery with a thin glass tube Luckily for you and me we have a safer way to measure blood pres sure today Even though Bernoulli was working with a liquid the same principle works for gases such as air Scientists classify both liquids and gases as fluids since they flow You can see Bernoulli’s principle at work by doing this simple experiment Hold a long strip of paper a dollar bill works well tucked tightly just under your bottom lip Blow hard directly outward and the strip will rise Fast-moving air creates a low pressure above the paper and the strip lifts Now let’s put Bernoulli’s principle to work and learn more about the science of flight Four Forces Flight is governed by four forces lift thrust drag and weight
Lift Thanks to Mr Bernoulli we now know that as air moves over an airfoil airplane wing helicopter rotor blade etc the air over the top has to travel a greater distance Because it travels a greater distance in the same amount of time it moves faster than the air mov ing under the wing Faster air has lower pressure than slower air High pressure under the wing will lift the wing up toward the area of lower pressure Lower pressure air Lift Wing Higher pressure air F L I G H T S C H O O L 3 Thrust Thrust comes from the engine on most traditional airplanes or from the rocket engine on a rocket Thrust causes the plane to fly forward However since you won’t be using engines in this book your flying machines thrust will come from other sources You will
