AirplanesHow an Airplane flies?

Airplanes

•Thrust (B)

•Drag (D)

•Weight (C)

•Lift (A)

Aerodynamic Forces

Airplanes

Straight and Level Flight

Thrust = Drag

Lift = Weight

AirplanesThrustAerodynamic force created by an airplane in order to overcome drag.

•Propellers

•Jet Engines

•Rockets

Means of Thrust

AirplanesDragAn aerodynamic force that resist the motion of an object Through a fluid (air and water are fluids)

The amount of drag an airplane creates depends on:•Size and shape of the plane.•Speed of an airplane.•Density of the air.

Landing gears areretracted to reduce the drag.

Airplanes

Every object on earth has weight (including air)

Weight

Airplanes

Aerodynamic force that holds an airplane in air.Most of the lift required to keep the plane aloft is created bythe wings.

Lift

Airplanes •Particles split at the leading edge, and they come together at the trailing edge of the wing.•Since the particles on top travel longer distance in same amountof time, they must be traveling faster.

Bernoulli’s Theory: The speed of a fluid increases, its pressure decreases.•Faster moving air on the top creates a low pressure on the top.•The low pressure on the top essentially “sucks” the plane wingsupward.

Longer Path Explanation

Airplanes

Interesting Things about wings

•The Angle of Attack

•Flaps

•Slats

•Wing Shape

AirplanesWing Shapes

Stunt Plane

Supersonic Jet

AirplanesAngle of Attack

The angle that the wing presents to oncoming air, and it Controls the thickness of the slice of air the wings is cutting off.

As it controls the slice, the angle of attack also controls the amount of lift that the wing generates.

Zero angle Shallow angle Steep angle

AirplanesTo compensate for different speeds (Cruise speed 901Kph and Landing speed 332Kph) Airplane wings are equipped with: Flaps airplane wings have moveable sections at the trailing

edge . •are extended rearward and downward

same function as Flaps, but attached at the front of the wings

Slats

Airplanes

Propeller: provides the thrust that moves the plane forward

•Has an angle of attack•Angle of attack changes along the lengthof the propeller•The angle is greater toward the center because the speed of the propeller through the air is slower close to the hub.

Some props have an adjustable pitch: propellerAngle changes depending on air speed and altitude

AirplanesHorizontal and Vertical Stabilizers

Tail of airplane has two small wings: horizontal and vertical stabilizers.

Horizontal: Controls up and down

Vertical: Controls left and right

AirplanesControlling the Direction

Rudder controls Yaw

Ailerons controls Roll

Elevators controls Pitch

AirplanesElastic Band Airplane Facts:•In 1909 American record for distance flown with a rubber band powered airplane was just over 200 feet

•In 1916 , Thomas Hall flew his model plane 5337 feet

•In 1924, Robert V. Jaros flew a model 7920 feet in 10 minutes and 14 seconds

•Today model airplanes fly for over 40 minutes.

AirplanesReferences•Google Search Engine•Mike’s Free Gifs•How Stuff Works