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shoe-box-glider-project Powered By Docstoc

                Produce a design that incorporates a shoebox as part of your glider. Additionally your
                Shoebox Glider will have to meet the criteria and constraints listed below. Your
                challenge is open-ended and involves a variety of collaborative and creative problem
                solving efforts!
Instructional Objectives:
                      Students will research the dynamics and forces of flight.
                      Students will apply their understanding of flight to the design, construction, and
                         test flight of a shoebox based glider.
                      Students will collect measurements and calculate glide-slope and aspect ratios.
Research Questions:
                1. Name the forces experienced by a glider in flight?
                2. What major design issues need to be considered for any flying machine?
                3. What forces affect all things that fly?
                4. Can you name at least three careers in aviation?
                5. What is a ratio?
                6. What does a glide slope ratio indicate?
                7. Which ratio indicates the best glide slope?
                         a. 8:4
                         b. 10:5
                         c. 4:1
                8. Which glide slope ratio indicated that a glider never flew?
                         a. 1:2
                         b. 0:5
                         c. 10:1
                9. What does the aspect ratio measure?
                10. Is there a relationship between glide slope and aspect ratios?
                11. What is an airfoil?
Shoebox Glider Criteria:
                a. The glider must move forward for at least 15 feet.
                b. The glider must demonstrate an efficient positive glide slope ratio.
                c. The glider must not break upon landing.
                d. The glider’s glide slope and aspect ratios must be determined.
                e. The glider must have good creative design and use of materials.
Shoebox Glider Constraints:
                a. The glider must include an intact shoebox in its design.
                b. There are no material constraints.
                c. All projects are due beginning of class Monday.
Release Point:
                The glider will be launched from the top of the stairs in the courtyard.

The Glide Slope Ratio
               Glide Slope is a number that indicates how well your designed shoebox glider
               flies through the air in terms of its forward distance vs. its drop in altitude.
               Glide Ratio = Horizontal Distance divided by the Change in Altitude.
               Another way to think of this is to ask, how far did the glider travel forward for
               every foot it dropped in altitude?
               For example: You released your Shoebox Glider from atop a 10-foot high ladder.
               Your glider traveled 50 feet before landing on the floor.
               Horizontal Distance = 50 feet
               Change in Altitude = 10 feet
               Dividing Distance (50) by Altitude (10) = 5 The Glide Ratio is 5
               50/10 = 5/1 = 5 The glider flew forward 5 feet for every 1-foot drop in altitude.

                 Orville and Wilbur Wright built their airplanes over one hundred years ago. After a lot of
                 testing and experimentation, they made several successful flights. By today's standards,
                 their designs were simple, but they discovered a lot about aircraft design and
                 aerodynamics. Now you have the chance to learn some of these same lessons for
                 yourself. First, let's look at the parts of a plane.

A full-size glider has four main parts:

                                    Fuselage (the body of the plane)
                                    Wings
                                    Control Surfaces (movable sections of the wing and tail)
                                    Landing Gear (usually just a single wheel)

For your project, your glider will likely only have the first two things- the fuselage and the wings. You
probably noticed that the above list does not include an engine. A glider, by definition, has no engine. So
what makes it fly? We'll get to that in just a minute...
A full-size propeller plane has six main parts:

                                    Fuselage
                                    Wings
                                    Propeller
                                    Engine
                                    Control Surfaces
                                    Landing Gear

So now let's get back to how airplanes fly. As you can probably guess, the way a propeller airplane flies
is a bit different than the way a glider flies. In both cases, however, it's all about the forces! Four forces
act on propeller airplanes: weight, lift, drag, and thrust.

Image from NASA

On the other hand, only three forces act on a glider: weight, lift, and drag.
Image from NASA

What are the effects of each of these forces?

                                   Weight: This force is caused by gravitational attraction to the earth.
                                    Weight depends on the mass of the airplane itself, plus its payload.
                                    What is a payload? It includes things like passengers, luggage, and
                                    fuel. Weight resists flight.
                                   Lift: This force is created by the motion (velocity) of the airplane
                                    through the air. Lift overcomes weight to make the plane fly. Most of
                                    the lift is generated by the wings through their design and angle. Air
                                    pressure also affects lift. Bernoulli's Principle states that the fast
                                    moving air is of lower density than slow moving air and has a lower
                                    pressure. The difference in air speed (and thus air pressure) above
                                    and below the wing produces lift.
                                   Drag: As an airplane moves through the air, the air opposes its
                                    motion, creating drag. This is also known as air resistance. This force
                                    acts in the opposite direction of the plane's flight. The shape and
                                    velocity of the plane and the air around the plane affect drag. Drag
                                    resists flight.
                                   Thrust: This force is created by the engine and the propellers. Thrust
                                    overcomes drag to make a powered airplane fly. In a propeller plane,
                                    the propellers push air backwards, making the plane move forward.
                                    Since gliders have nothing to generate thrust, there is no force to
                                    oppose drag.

Once a glider is launched, it will gradually slow down until it can no longer generate enough lift to
oppose its weight. A well-designed glider, however, can stay aloft for a long period of time and fly great
distances by taking advantage of lift and lessening the effects of weight and drag. Propeller airplanes on
the other hand can depend on their propeller and engine- and the resulting thrust- to keep them aloft.
One of their main limits is their fuel supply, which powers the engine and propeller in the first place! (It's
also good for propeller planes to consider the effects of the other forces, since this can make the
propeller and engine work more efficiently.)
How can you use what you know about the forces acting on your plane to make it fly better? You might
want to consider the following:

                                Weight
                                     o  Will a heavy plane or a light plane be more effective?
                                     o  Consider that less weight means there is a smaller force to
                                        oppose lift.
                                    o But, too little weight might cause problems, too!
                                Center of gravity
                                    o This is the theoretical point where the weight of the plane is
                                    o What will happen if the center of gravity is too far forward or
                                        too far back?
                                Aerodynamics & drag
                                    o How can you make the shape of your plane and its wings
                                        more aerodynamic?
                                    o Which surface produces less friction: a smooth surface or a
                                        rough surface?
                                Wing design
                                    o The wing aspect ratio is the ratio of the wing's span to its
                                    o Long, thin wings (high wing aspect ratio) are more efficient-
                                        they produce less drag compared to the lift that they
                                    o Short, stubby wings (low wing aspect ratio) are sturdier and
                                        more maneuverable.
                                    o Which design is better in the plane that you'll be building?

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