Heavy Pack–a–AC Load
You have been asked to investigate wing designs for airplanes. The goal is to fly an airplane with the most heavily loaded wing possible. You will be expected to design the wing and test it on a fuselage of stock design. For your wing you must decide on the type of wing, the span, chord, planform shape, and lastly the airfoil shape.
Wing loading (WL) will be based on the lift per square inch of wing area
WL = L / S
- WL is the wing loading, a number to be maximized.
- L is the lift, equal to the weight of the airplane in level flight.
- S is the wing area.
To complete the requirements of this challenge you must:
Define the Problem
- Write a brief description of the challenge in your engineer's notebook
- Identify criteria and specify constraints. Review the lists below and ask your teacher if you have any questions.
- Listen to the presentation about airplanes. Take notes.
- Consider the various planforms presented.
- Consider the materials available for making wings.
- Sketch your various ideas in your engineer's notebook.
Develop a Solution
- Design a wing for maximum wing loading.
- Pick a planform shape.
- Pick a span (b).
- Pick a chord (c) or aspect ratio (A).
- Sketch your wing design. Indicate the span and chord. Calculate the area (S) and aspect ratio (A)
- Pick an airfoil shape
- Document the process in your engineer's notebook
Construct and Test a Prototype
- Construct a standard fuselage and tail for the model airplane
- Attach the specified motor and propeller, and the landing gear.
- Construct your wing based on your design.
- Assemble the model airplane so that it can fly around the power pole.
- Add cargo for maximum wing loading.
Evaluate the Solution
- Demonstrate the performance of the airplane in a series of test runs. For each run:
- Weigh the airplane.
- Determine the wing area (S) — Sketch the wing and show how you calculated the area.
- Calculate the wing loading (WL) at which the plane was flying.
- Make changes in the weight of the airplane (add or remove cargo), or in the design of the wing, or in the configuration of the control surfaces, to maximize WL. Entirely new wings may be designed, constructed, and tested.
- Retest after each change and recalculate WL for the new conditions.
- Enter your score in the leader board.
Present Solution Document your solution in your engineer's notebook. Submit your sketches and calculations for evaluation.
The evaluation of the task will be based on the following:
- Product—Airplane (20 points)
- An innovative, correct, detailed, and well-engineered solution. Well constructed to close tolerances. Parts symmetrical
- Main wing has efficient planform shape. Main wing has modern airfoil shape faithfully reproduced.
- Control Surfaces follow pattern and are sanded to Bernoulli Airfoil shape.
- Finished to be aesthetically pleasing.
- Performance (20 points). Your performance will be based on your WL
compared to others in the class, with the maximum WL receiving 20
points. Any plane that flies will receive a passing grade.
- Presentation (10 points)—Engineer's notebook and sketches.
- Content: Wing Sketched. Formulas Shown. S, A, WL calculated
- Number every page sequentially (outside top) in a bound notebook.
- Designer ± witness sign and date each page.
- Date each entry. Label all figures and calculations.
- Chronicle problems encountered and your ideas to fix them.
- Information given in entries is proportional to the amount of time given per class period.
- Students will design, build, and test their device individually.
- The plane that you design and build must fly around the power pole at least three times.
- Each student will analyze the data obtained.
- All test must be done with no more than the maximum voltage provided by the power supply.
- Ascertain from your teacher if there is a limit on span in your testing area.
- Each airplane may only use one of the motors and propellers provided by the teacher.
Last updated on 12 April 2016 by P. A. Wiedorn