Reference no: EM133493014
Case Study: Over the duration of this course, you will continuously work to investigate and document the specific aerodynamic and performance characteristics of a selected example aircraft. The overall goal is for you to create a comprehensive aircraft document, such as a PowerPoint Presentation, that will allow a new user/owner/operator of your example aircraft to determine optimum performance during various types of operation. You will use some of the basic aerodynamic principles discussed in this course and apply them to your selected aircraft.
Each week, you will create a different part/aspect of the overall documentation, building on your previous work, and the additional insights gained in that respective module. Modules 2, 3, 5, 7, and 8 will require you to add content and you will submit the finished presentation during Module 9 for your fellow students to critique and comment. Module 4 is about "Jet Performance" and will not be included in your final presentation.
The subject for your project investigations will be a specific propeller-driven general aviation (GA) aircraft of your choice. However, to simplify some of the more complex matters, choices are restricted to single-engine, monoplane configurations (i.e., no twin-engine, no bi-plane, no jet).
To provide some ideas, consider the following example aircraft:
Cessna (150, 152, 162, 172, or 182)
Piper (Cub, SuperCub, Comanche, or Cherokee)
Cirrus (SR20 or SR22)
Beechcraft (Bonanza or T-6)
Mooney (M20)
Pilatus (PC-6, PC-7, PC-9, PC-12, or PC-21)
Diamond (DA-20, DA-40, or HK-36)
Vans (any RV)
etc.
For this module assignment, your task will be to begin creating an instructional document, such as Powerpoint, that explains how to find key airfoil aspects and related attributes of lift production for your selected aircraft. For more information on creating your presentation, visit the Field Exercises and Presentation Resources page.
The document below outlines the requirements for the first entry of your Independent Project.
All provided answers must exemplify the concepts with specific numbers/values for your aircraft. For example, we are not looking for the stall speed as given in the POH or on Wikipedia, but want to see how you derived a calculated stall speed based on your airfoil data, the particulars of your selected aircraft, and the application of the lift equation. Therefore, you will need to research some additional information and/or use your formula knowledge from this week's readings to derive all the variables necessary to solve the lift equation.
As a starting point and the minimum content to cover, a shortlist of considerations and discussion points are provided below and can be directly copied into your presentation.
Question A. Main airfoil for your selected aircraft
- Stall AOA and associated CLmax
- Zero-lift AOA
- Comparison of your main airfoil to a symmetric airfoil
Question B. Resultant attribute discussions for your selected aircraft
- Calculated stall speed
- How does lift change with airspeed if a constant AOA and altitude are held? (provide specific examples)
- How does lift change with altitude if a constant AOA and airspeed are held? (provide specific examples)
- How do the required CL and AOA for your specific aircraft (at a specific weight) change with changes in airspeed? (provide specific examples)
- What happens if the required CL is larger than CLmax of your airfoil, and what speed regime is usually associated with that condition?
The key to answering some of the questions is to provide specific calculation examples for your aircraft that showcase the points made. There are various forms in which you could do so, including self-generated tables and graphs or comparisons of key cases (e.g., comparing a low, medium, and high altitude case). You will notice that all such calculations are ultimately based on repeated but different applications of the lift equation. Therefore, in order to apply the lift equation, a couple of aspects about your aircraft have to be known (i.e., researched) or assumed (i.e., detailed in your explanations). These parameters include:
- Wing configuration (may include wingspan, wing area, aspect ratio, average chord, etc. - keep in mind that the lift equation ultimately requires wing area to calculate with.)
- The weight of the aircraft (probably somewhat assumed but should definitely fall between the empty and max weight of the aircraft)