How does an airplane fly

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How does an airplane fly?
WILLIAM T. DWYER TECHNOLOGY EDUCATION
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OBJECTIVES

• Understand the concept of pressure.
• Explain Bernoulli's principle as it pertains to
  lift.
• Demonstrate how airplanes fly

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Interdisciplinary Connections
Physics Investigate gravity, forces, pressure,
and velocity. Chemistry Study fluids, air,
pressure, density, and viscosity. Mathematics
Perform calculations pertaining to velocity,
acceleration, force, and pressure.
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an airplane must CONTROL forces
LIFT
Air on top of the wing moving faster than the air
below (Bernoulli effect).
DRAG
THRUST
The force necessary to overcome gravity and drag.
Resistance created by air.
GRAVITY
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an airplane must CONTROL forces
LIFT
DRAG
THRUST
GRAVITY
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Bernoulli's principle concept stating that as
a fluid's speed increases, its pressure
decreases.
lift force exerted on the underside of a wing
by air moving over the surfaces of the wing.
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(No Transcript)
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Thrust

• Amount of pressure required to keep 1 pound
  object stationary against the force of gravity
• On earth acceleration of gravity is 32 feet per
  second
• Measured
• pounds of thrust or Newton's

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Q Why does a wing cause an airplane to rise into
the air?
DEMO
A Air moving over the curved surface of the top
of the wing has more distance to travel than the
air under the wing. Thus the air on top of the
wing is moving faster than the air below. This
creates an area of lower pressure above the wing,
causing a force to be exerted under the wing and
lifting it upward. If the air moves fast enough
over the surface of the wing, the lift force can
become sufficient to overcome gravitational
forces. The wing can then be said to be flying.
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HOW DO WE CONTROL AN AIRPLANE?
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WHAT ARE WE CONTROLLING?
Remember the X, Y, Z axis?
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REVEIW

• Forces
• thrust
• Newton's third law of motion
• drag
• lift
• Bernoulli effect
• gravity
• Air has weight, pressure
• Control
• Pitch
• Yaw
• Roll