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 The angle at which lift stops increasing and begins to decrease is called the burble point.

The Four Forces of Flight Angle of Attack 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.

Lift Variables 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 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