1. Conestoga Valley High School Aviation Technology
The Airfoil
Conestoga Valley High School
Aviation Technology
Originally commissioned in 1966, the SR-71, nicknamed "Blackbird," flew missions for over 30 years, becoming one of the most storied aircraft of all time. Capable of traveling at speeds in excess of Mach 3 (over 2000 mph), at altitudes of up to 85,000 feet, and with a combat range of nearly 3000 miles, the SR-71 was a technological marvel at the time of its creation.

2. The Airfoil Airfoil Cross-sectional shape of a wing
Develops lift when air flows around it
Two Types
Symmetrical and Unsymmetrical
Symmetrical
Unsymmetrical

3. Air as a Fluid? Air = Fluid Bernoulli’s Principle Changing Pressure
Mass
Flows and can push on an object
Holds no shape when pushed on
Bernoulli’s Principle
Air travels faster over camber to create a lower pressure
Changing Pressure
Caused by increasing speed over the airfoil
Lift
Increase speed and AOA
Airfoil Stall 3

4. Airfoil Types Symmetrical Unsymmetrical
Same shape on the top and bottom
Advantages
same lift performance upside down as right side up
Better design for stunts
Disadvantages
No lift at 0 degrees AOA
Lower lift to drag ratio at the same AOA then unsymmetrical
Unsymmetrical
Not the same shape on the top and bottom
Advantages
has lift at O degrees AOA
higher lift to drag ratio at the same AOA then symmetrical
Disadvantages
Not as good at acrobatic maneuvers
Air show Yak-54

5. Review Questions Review Questions What is an airfoil?
What are the two types of airfoils?
What causes the pressure changes across the wing?
Why does an unsymmetrical wing have more lift at 0 degree AOA?
Which type of airfoil would a stunt plane use?
Cross-sectional shape of a wing
Symmetrical & Unsymmetrical
Increasing speed
Bernoulli’s Law is in effect more
Symmetrical 5