Page 108 - (DK) Danger! Open with Extreme Caution!

Early flight In 1783, the French Montgolfier brothers rose up into the sky in an unsteerable hot-air balloon. By the 1890s, a pair of German brothers, Otto and Gustav Lillienthal, made steerable flights in gliders. Close on their tail in 1903, yet another brother team, Orville and Wilbur Wright, made the first controlled and powered aircraft flight. We had liftoff!

The force that resists the motion of a moving object and slows it down is called drag. Aircraft are designed to let air pass around them with less drag.

Drag The force that pulls the aircraft back to Earth is weight. Aircraft are heavy, but they are constructed so that their weight is spread from front to back, keeping everything balanced.
across the oceans. Imagine the perils the first aviators faced as they
sail for unknown waters towards some distant destination. Find out
chased the dream of human flight. Consider the danger of setting
the safety of solid ground behind and journey into the skies or
how to be a highflier, as well as learning what floats your boat.
Feeling up in the air or out to sea? Maybe it’s time to leave
The force that acts to push the aircraft up is called lift. The way air moves around the wings, together with the shape of the wings, give the aircraft lift. Up, up, and away! Weight What happens when something goes wrong? Thankfully, most air crashes are not fatal. Between 1980 and 2000, for example, there were 568 plane crashes in the U.S., and 90 percent of the victims survived. To improve your chances, it’s wor

DANGEROUS

Lift Propellers or jet engines create powerful thrust to move the aircraft forward to its destination. Fire up all cylinders! Air crashes
JOURNEYS

Taking flight Aircraft stay in the air because of four basic forces: lift (going up), weight (pulling down), thrust (moving ahead), and drag (resisting motion). In order for aircraft to fly straight and level at a constant speed, the forces must act in pairs. That means thrust must be equal to drag and lift must be equal to weight. Thrust

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