Transcript Document
Investigation Three: Aviation and Airplane BasicsThe Battle of the Forces • An airplane flies because the air moving over and under its wings travel at different speeds creating lower pressure above the wings which causes the higher pressure below the wings to push up. Lower Pressure Faster Air Slower Air = = Higher Pressure LIFT! Look carefully at the following pictures and tell me which sumo wrestler represents the higher pressure under the wing. Sumo Ballet? • Airfoil – the special shape of an airplane’s wing which creates lift. • Force – Energy, such as a push or a pull, that changes the motion or shape of an object. • Lift – the force perpendicular to relative wind flow and opposite the force of gravity that allows aircraft to fly. /gravity Lift (3:14) • Gravity – the force that pulls all objects toward the center of the Earth. Bernoulli's Principle of Lift • Air Planes are able to fly because of lift which is what holds an airplane up. Lift is created by differences in air pressure explained by Bernoulli's principle. It states that air moving fast has a lower air pressure than air moving slower underneath. • The way the airplane's wings are shaped forces the air going over the top of the wings to speed up in order to reach the end edge of the wing at the same time as the air traveling under the wing. The bottom air has to travel a shorter distance to the end of the wing so that the air does not have to travel fast. • These varying speeds create a difference in pressures. This air pressure difference exerts a upward force on the wings that keeps the airplane in the air. • Wing shape and speed help lift occur. • If a plane is too heavy lift will not occur. The Four Forces of Flight (2:06) • Thrust – a force that moves an object forward. • Pilots use flaps to raise and lower the tilt of the wings making the plane go up and down. • Drag – the resistance of air to objects moving through it, i.e. wind resistance. • Streamlined – having a contoured design to offer the least resistance to air or water, allowing it to move smoothly. Which ball can you throw further? Why? Which vehicle is more streamlined? Streamlined (1:05) Experimental Designs Unsuccessful Flying Machines FIG. 4. -- DE BACQUEVILLE -- 1742. http://invention.psychology.msstate.edu/i/Chanute/library/Prog_Wings_Nov1891.html Experimental Flops (0:13) Human Powered Flight (1:09) • The Wright Flyer • Biplane – an airplane with two sets of wings, one above the other. • Multiwinged Airplane • Monoplane – an airplane with one set of wings. • Frank Whittle – the British pilot and engineer who designed the first jet engine. • Airplane designers use wind tunnels and computers to design modern airplanes. Great Names in Aviation History • Aviation – the science of building and flying heavie than-air craft, including airplanes, gliders, and helicopters. • Orville and Wilbur Wright – made the first airplane flight in history in 1903 at Kitty Hawk, North Carolina. The flight lasted 12 seconds and the plane traveled 120 feet. Barnstormers (1:34) • Bessie Coleman – was the first African American woman t earn a pilot’s license. She helped break down racial and gender barriers in the aviation industry. Bessie Coleman (1:20) • Chuck Yeager – the pilot of the first plane to fly at Mach 1, faster than the speed of sound, breaking the sound barrier. Plane Exceeds Speed of Sound (0:59) • Mach – short for Mach number, the speed of sound (660 miles per hour). Mach 2 would be twice the speed of sound. Speed of Sound (2:10) • William Boeing – was an airplane inventor and innovator who developed state of the art airplanes and founded the Boeing Airplane Company. Lighter than Air Aircraft Crash of the Hindenburg (2:57) Hughes Tests Plane (1:45) Fig 5 Downwash and wing vortices in the fog. (Photographer Paul Bowen, courtesy of Cessna Aircraft, Co.) Dr. Dad: Flight (14:17) Review Questions • Where is higher air pressure located in relationship • • • • • • • to a planes wings? Which force allows a plane to overcome gravity? What helps lift occur? What prevents lift? What is drag? What is the term for having a contoured design to offer the least resistance to air or water? What is a biplane? What is a monoplane? Review Questions Continued • What do airplane designers use to design modern • • • • • • • airplanes? What is aviation? What are the Wright Brothers known for? Who was Bessie Coleman? What did Chuck Yeager accomplish? What is Mach? Who was William Boeing? What is a system? The End! Variables Experiments Vocabulary • System – a set of objects that are related in some way and can be isolated for study.