Science: Wind Tunnel Presentation

1. What creates lift?

Scott: Air movement over the wing. Lynn: A low pressure area is created on top and a high pressure area on the bottom.

2. What creates drag?

Scott: Anything in the way (why airplanes are sleek). Lynn: Resistance through the air.

7. How does lift and drag contribute when flying a plane?

Scott: Balancing act because lift is is taking you up drag is pulling you back Lynn: Drag has to be over come in order to move and the air over the wing to create lift and over come the drag.

4. Why did you choose the 1903 Flyer?

Scott: Because there is not as smooth surface on the bottom. Lynn: Because of the way the air has to travel it will create turbulence (on the bottom)

8. Why is knowledge of lift and drag important when flying?

Scott: For any pilot to be a good pilot, the pilot needs to understand lift and drag. Lynn: As an engineer you would need to know the pull on the wings would be able to get fast enough to lift the plane off the ground.

10. Why is aviation important to you?

Scott: It is a hobby, escape, a way to bond with family and extended family (young aviators). Something he is most proud of and brings people together "Out of all of my business success young aviators is what I most proud of". Lynn: "When you get off the ground you are in another world. You are not tied down you feel free. In one word it is explained as freedom."

9. What kinds of jobs can you have if you are interested in aviation?

Scott: Pilot (all kinds commercial, stunt, bush, etc.) Designer or builder (in the military for every pilot to a plane there are 100 other people doing different jobs to that same plane) Lynn: Pilot (corporate) Mechanic Flight instructor Aeronautical Engineer (primary branch of engineering concert with the research, design process, development, construction testing, science and technology of an aircraft and spacecraft)

5. What are some main differences between the airfoils that would affect the lift and drag?

Scott: The different characteristics such as, the fatter the wing is the more stable the wing. The thinner makes it easier to go upside down and do aerobatics. Lynn: Can fly both upside down and right side up because it is a plan designed for acrobatics (took acrobatic flying class learned how to do a snap roll by jerking the stick all the way back until the aircraft is stalled and the rudder starts to spin)

6. How does aviation affect the world?

Scott: Transportation of food and goods. It affects everything today. Lynn: It is a major transportation breakthrough because people are able to get around faster. A large step up in speed. The world became smaller over night.

Stall:

sudden decrease in lift

Results Table

- The table shows the four airfoils I chose - The angles of attack 0-35 - Measured drag and lift - Subtracted drag and lift constant - Computed drag and lift

Procedure 1

1.I started by choosing the airfoils on http://airfoiltools.com/ •1903 Flyer - Wright Brothers •Pitts Special S1-C - Lil' Stinker: •Lockheed Model 10 Electra - Amelia Earhart: •The Fokker Dr. 1 -Red Baron:

3. Which of the following airfoils would you expect to have the most drag?

1903 Flyer - Wright Brothers

Procedure 2

2. I built the airfoils using balsal wood and butcher paper. To build them I cut 5 ribs using the print off from http://airfoiltools.com/ and drilled holes into the 5 ribs in order to put 2 spares into them and spread each evenly. Then I glued each rib to the 2 spares. After that dried, I wrapped and glued butcher paper around the ribs.

Procedure 3

3. Once all 4 of the airfoils were dry, I set up the wind tunnel by placing each scale in the correct position and tared each scale to 0 grams

Procedure 4

4. Then, I opened the plexi glass and placed the first wing segment in between the protractors each spar fits through a gap on the protractors.

Procedure 5

5. Next, I loosen each screw and set the angle of attack (0-30), set the bars on the scales, and close the plexi glass lid

Procedure 6

6. After that, I turn the fan on to the second notch and watch the scales for lift and drag (tap on the table to reduce the friction of the bar sitting on the scale measuring lift)

Procedure 7

7. After watching the scales until there is a number that sits on each scale I record the data in my table and later graph it.

Procedure 8

8. This is then repeated with the other airfoils. And one test after each airfoil is done to subtract the lift and drag constants (bracket creates lift and drag itself and that is what I a, subtracting)

Young Aviators

A special group for kids 8-18 years old coming together to build projects and learn about aviation. For example our current project is the nose of a B-25 full size replica to take to an air show in Osh-Cosh air show in Wisconsin.

Bernoulli's Principal:

Bernoulli's Principal is a component of lift and states... As the velocity of moving fluid increases, the pressure within the fluid decreases. When the air meets at the leading edge it separates moving across the top and bottom of the airfoil. The top of the air foil is longer than the bottom and in order for the air moving from the top and bottom to meet at the trailing edge, at the same time the air on the top must move faster than on the bottom. The increase in velocity creates less pressure on the top and more on the bottom. Because there is more pressure on the bottom the airfoil is pushed up and creates lift.

Conclusion

Changing the angle of attack does affect lift and drag of an airfoil because as the angle of attack changes from 0-35 degrees throughout the process, lift quickly increased and drag slowly increased. After a certain angle of attack drag started increasing quickly and lift increased slower or decreased. But, only 2 of the airfoils stalled the 1903 Flyer and the Fokker Dr. 1. Although the Pitts was close to stalling if it continued the Pitts would have stalled. Overall, the results of the airfoils showed the lift tapering off as drag increased.

Results Graph

Flyer Lift: increased at a constant rate until after the angle of attack was at 25 degrees there was a sudden decrease and the wing segment stalled Drag: started out increasing slowly until after angle of attack was at 15 degrees the drag started increasing quickly Fokker Lift: Increased at a constant rate until after the angle of attack was at 30 degrees where it stalled Drag: Did not increase right away increased after the angle of attack was 15 degrees Electra Lift: Increased at a constant rate and never stalled but was very close Drag: Decreased a little and gradually increased until after the angle of attack was 20 degrees and drag started to increase very quickly Pitts Lift: started increasing quickly and never stalled Drag: Did not start to increase right away until after the angle of attack was 10 degrees

Focus Question

How does changing the angle of attack affect lift and drag?

Interview

I interviewed 2 private pilots Lynn Miller and Scott Sthat both have built their own airplanes. Also, they are both founders of Young Aviators an aviation group for kids.

Hypothesis

If I change the angle of attack from 0°-35° at 5 degree increments I think the lift will overcome the drag until a certain angle of attack. It then will cause the airfoil to stall and the drag will increase and overcome the lift. I think this because at a certain angle (25 or 30 degrees) the air will not travel over the top of the airfoil causing drag to pull back the airfoil.

Newton's Laws

Newtons Laws also apply to lift because of how a wing deflects airflow (cause something to change direction inter posing something)

Similarities and differences

The Flyer, Fokker Dr.1 and Pitts drag all started out slow until the Pills increased after the angle of attack of 10 degrees The Flyer and Fokker Dr. 1 decreased after the angle of attack of 30 degrees

Lockheed Electra 10e

The Lockheed Model 10 Electra was a twin engine, all metal monoplane airliner developed by the Lockheed Aircraft Corporation in the 1930s to compete with the Boeing 247 (passenger airliner) and Douglas DC-2 (passenger and military transport). The type of plane gained considerable fame as one was flown by Amelia Earhart on her unlucky around the world expedition in 1937.

Wind Tunnel:

a tunnel like apparatus for producing an airstream of known velocity past models of aircrafts, buildings, etc., in order to investigate flow or the effect of wind on the full size object

Camber Line:

curve that is halfway between the upper and lower surfaces of the airfoil. Camber is usually designed into an airfoil to increase the maximum lift coefficient.

Angle of attack:

the angle between the chord line of the wing and the vector of relative wind

Leading Edge:

front edge of an airfoil

Chord Line:

imaginary straight line joining the leading and trailing edges of an airfoil

Four Forces of Flight:

lift, drag, thrust, and gravity

Training Edge:

rear edge, where the airflow separated by the leading edge rejoins

Airfoil:

shape of a cross-section of a wing

Drag:

the force on an object that resists its motion through a fluid (the reason I used the word fluid instead of air is because in physics air acts like a fluid because it flows opposed to a solid)

Lift:

the force that directly opposes the weight of an airplane and holds the airplane in the air

Airspeed:

the speed of an aircraft relative to the air through which it is moving

Maximum Lift Coefficient:

the stall angle of an airfoil

Wright Brothers 1903 Flyer

•After building and testing three full-sized gliders, on December 17, 1903, the Wright brothers took their successful first flights of a heavier than air flying machine at Kitty Hawk, North Carolina. The Wright's first powered airplane flew a 12 second flight, traveling 120 feet, with Orville Wright piloting. The best flight of the day, was with Wilbur Wright at the controls he covered 852 ft in 59 seconds. •This airplane, known as the Wright Flyer, sometimes referred to as the Kitty Hawk Flyer, was the product of four years of research and development conducted by Wilbur and Orville Wright beginning in 1899. During the Wright's design and construction of their experimental aircraft they also pioneered many of the basic techniques of modern aeronautical engineering, such as the use of a wind tunnel and flight testing. •Their accomplishment encompassed not only the breakthrough first flight of an airplane, but also the equally important achievement of establishing the foundation of aeronautical engineering. (Flight technology)

Red Barron Fokker Dr. I

•The Fokker Dr.I was a World War I fighter aircraft built by Fokker-Flugzeugwerke. The Fokker Dr.I was a famous plane of World War One, only 320 of the Fokker Dr.I triplanes were built •Anthony Fokker designed and built the Dr.I (Dreidecker) and delivered the first triplanes to Manfred von Richthofen in late August 1917. After a brief familiarization flight, the "Red Baron" took aircraft number 102/17 up on September 1, and promptly shot down a British R.E.8 •The Dr.I saw widespread service in the spring of 1918. It became renowned as the aircraft in which Manfred von Richthofen (Red Baron) gained his last 19 victories, and in which he was killed on April 21, 1918. •Reinhold Platz was a German aircraft designer and manufacturer in service of the Dutch company Fokker.

Pitts Special S1-C

•The Lil' Stinker is the oldest surviving Pitts Special. The Little Stinker was the second aircraft constructed by Curtis Pitts. Pitts introduced the S-1 in 1945, the first of a famous line that dominated aerobatic competition throughout the 1960s and 1970s because of the small size, light weight, short wingspan, and extreme agility. Subsequent models still fly in all aerobatic categories and are standard aircraft for advanced aerobatic training. •Betty Skelton bought this airplane in 1948, and with it she won the 1949 and '50 International Feminine Aerobatic Championships. Her impressive flying skill and public relations ability heightened awareness of both aerobatics and the Pitts design.