Transcript Basic Aeronautics

Basic Aeronautics
Know the principles of basic aeronautics.
1. Describe the effects of angle of attack.
2. Identify the four forces of flight.
Review
Newton’s Three Laws:
1. A body at rest tends to remain at rest, and a body in motion tends to stay in motion,
unless an outside force acts on the body.
2. Force = Mass x Acceleration.
3. For every action there is an equal and opposite reaction.
The Four Forces of Flight
• Increase velocity of air around an airfoil shape = increases
the relative wind as it flows above and below the surface of
the airplane wing.
Angle of Attack
• Formed by the cord of the
airfoil and the direction of the
relative wind or between the
chord line and the flight path.
• Is not constant during a flight.
It changes as the pilot changes
the attitude of the aircraft.
The Four Forces of Flight
• Angle of Attack
The Four Forces of Flight
• Angle of Attack
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The angle at which lift stops increasing and
begins to decrease is called the burble point.
The Four Forces of Flight
• Angle of Attack
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The point at which the amount of lift generated is no longer sufficient
to support the aircraft in air is called the stalling point.
The Four Forces of Flight
• Lift can be increased in two ways
 Increasing the forward speed of the
airplane.
 Increasing the angle of attack.
• The pilot can increase the forward speed
of the aircraft by applying more power.
The Four Forces of Flight
• Lift Variables
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Atmosphere
Airfoil Shape
Wing Area
Weight
Thrust and Drag
The Four Forces of Flight
• Air Density and Lift
 Lift varies directly with air
density. At 18,000 feet air
density is about half that at sea
level. At that altitude an
aircraft will need to fly faster
maintain altitude.
The Four Forces of Flight
• Airfoil Shape
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It is extremely important to preserve
the characteristic curve that the
designers built into the airfoil.
Dents, mud, and ice are three
common things that can spoil the
built-in shape of the airfoil and
interfere with the performance of
the entire aircraft.
The Four Forces of Flight
• Wing Area and Lift
 The greater the surface area of
the wing, the greater the
amount of lift that will be
generated.
 Gliders and sailplanes are very
good examples of how a large
wing surface generates lift.
The Four Forces of Flight
• Weight
 There is a point where lift can no
longer overcome weight.
 The airplane must be constructed of
the lightest weight materials that
can be used.
 The weight of whatever the airplane
carries also receives very careful
consideration.
The Four Forces of Flight
• Weight
 Where the weight, or useful
load, is placed in the airplane
is another factor that has a
pronounced effect on how well
an airplane will fly.
The Four Forces of Flight
• Thrust and Drag
 Thrust is the force that propels the aircraft forward.
 An airplane cannot gain altitude or maintain straight and level flight
unless its engine is producing enough thrust.
 Without the needed thrust, weight has more influence than lift and
pulls the airplane toward the ground.
The Four Forces of Flight
• Thrust and Drag
 Drag is present all the time and can be defined as the force that opposes
thrust.
 The friction of air particles rubbing against all parts of the airplane
causes part of the total drag.
 The shape of something may create low-pressure areas and turbulence
that retard the forward movement of the aircraft.
Summary
1. Angle of Attack
2. The Four Forces of Flight