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For this module week, you will use your selected aircraft

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For this module week, you will use your selected aircraft. You will further use your selected aircraft in subsequent assignments, so be specific and make sure to stay relatively conventional with your choice in order to prevent having trouble finding the required data during your later research. Also, if you find multiple numbers (e.g. for different aircraft series, different configurations, and/or different operating conditions), please pick only one for your further work, but make sure to detail your choice in your answer (i.e.comment on the condition) and stay consistent with that choice throughout subsequent work.

• Your presentation is due by the last day of the module and should be created using Powerpoint or the presentation platform of your choice.
• The aircraft I chose is the cessna 172
• Independent Project: Drag For the speeds in the first column, start with your aircraft's stall speed, then continue in intervals of 20 or less knots (consider increasing the detail in the important portions near (L/D)max - see also this module's tutorial videos within the 3.2 Lectures and Tutorials), and continue to at least a speed of 300kts or higher if required to allow for answering the questions and explaining all drag phenomena. To create this table you can use the Excel Spreadsheet ASCI 309 Table Drag Table (XLSX) located under “Field and Presentation Resources”. V (KTAS) q (psf) CL CDP CDI CD CL / CD VS 60 80 100 120 140 160 180 200 220 240 260 280 300 College of Aeronautics | worldwide.erau.edu All rights are reserved. The material contained herein is the copyright property of Embry-Riddle Aeronautical University, Daytona Beach, Florida, 32114. No part of this material may be reproduced, stored in a retrieval system or transmitted in any form, electronic, mechanical, photocopying, recording or otherwise without the prior written consent of the University. DP (lb) DI (lb) DT (lb) To fill out your table and subsequently create a diagram with the total drag curve, you will need to research a variety of variables, formulas, and components. Again, the emphasis in this project task is on explaining your methodology as if you attempted to instruct someone unfamiliar with the aerodynamic details and relationships. Therefore, make sure to detail all assumptions, all formulas used, and all steps that were taken. The following will give you some starting points for your search and consideration. 1. Assumptions and conditions: o Assumed atmospheric conditions o Calculated dynamic pressure (second column; based on the assumed atmospheric conditions and KTAS) 2. Necessary aircraft information: o Wing size and configuration (e.g., AR & efficiency factor - if you can't find an efficiency factor for your aircraft, you can make an assumption [i.e., pick a value] somewhere between 0.75 and 0.85) o Weight (should, of course, fall between MTOW and empty weight of your aircraft) o Airfoil information (e.g., CLmax from last module & CDP - if you can't find the CDP for your entire aircraft, you can utilize the minimum drag for your airfoil and add a value of 0.02, which will account for the parasite drag of your aircraft's fuselage) or if you are still having trouble, just use a Cdp of .021 which is a common Cdp. 3. Required formula (for inputs see the formula summary ) 4. Resources and Inputs page) o Dynamic pressure o Lift equation (two forms: one solved for stall speed and the other solved for required CL) o Drag coefficients (CDi & CD) o Application of coefficients to find actual forces (Dp, Di, Dt) o Possibly wing geometry conversions (e.g., wingspan and area into AR or wingspan and average chord into AR) 5. Do not forget to create the diagram. Once created, utilize your derived table and diagram data to answer the following associated questions: A. What are the minimum drag parameters for your aircraft? o Minimum drag value D(min) o Speed VD(min) at which minimum drag occurs o Relationship between Dp and Di at D(min) B. What are the maximum lift to drag ratio CL/CD parameters for your aircraft? o (CL/CD)max value o Speed at which (CL/CD)max occurs C. Compare answers in A. and B. and comment on the findings. D. Explain which of your derived values will allow glide performance predictions for your aircraft and quantify best glide conditions with specific values. Page 2 of 2 V (KTAS) 113.3 120 140 160 180 190 200 220 240 260 Weight (W) Wing Area (S) Aspect Ratio (AR) e Temp Sigma (∂) CDP CLmax at Stall q= ∂ x V^2/295 (lb/ft^2) CL = W/qS CDI=[1/ (πeAR)] CL^2 CDp CD= CDP+CDI CL/CD Dp=CDp q S (lb) Di = Cdi q S (lb) 43.48 48.81 66.44 86.78 109.83 122.37 135.59 164.07 195.25 229.15 1.50 1.34 0.98 0.75 0.59 0.53 0.48 0.40 0.33 0.28 0.159 0.126 0.068 0.040 0.025 0.020 0.016 0.011 0.008 0.006 0.021 0.021 0.021 0.021 0.021 0.021 0.021 0.021 0.021 0.021 0.18 0.15 0.09 0.06 0.05 0.04 0.04 0.03 0.03 0.03 8.33 9.08 11.02 12.34 12.93 12.98 12.88 12.36 11.56 10.65 210.00 235.77 320.91 419.15 530.48 591.06 654.92 792.45 943.08 1106.81 1589.8 1416.0 1040.3 796.5 629.3 564.8 509.8 421.3 354.0 301.6 15000 230 5.3 0.85 Standard 1 0.021 1.5 295 Dt = Di + Dp (lb) 1799.8 1651.8 1361.3 1215.7 1159.8 1155.9 1164.7 1213.7 1297.1 1408.4 Independent Project: Drag For the speeds in the first column, start with your aircraft's stall speed, then continue in intervals of 20 or less knots (consider increasing the detail in the important portions near (L/D)max - see also this module's tutorial videos within the 3.2 Lectures and Tutorials), and continue to at least a speed of 300kts or higher if required to allow for answering the questions and explaining all drag phenomena. To create this table you can use the Excel Spreadsheet ASCI 309 Table Drag Table (XLSX) located under “Field and Presentation Resources”. V (KTAS) q (psf) CL CDP CDI CD CL / CD VS 60 80 100 120 140 160 180 200 220 240 260 280 300 College of Aeronautics | worldwide.erau.edu All rights are reserved. The material contained herein is the copyright property of Embry-Riddle Aeronautical University, Daytona Beach, Florida, 32114. No part of this material may be reproduced, stored in a retrieval system or transmitted in any form, electronic, mechanical, photocopying, recording or otherwise without the prior written consent of the University. DP (lb) DI (lb) DT (lb) To fill out your table and subsequently create a diagram with the total drag curve, you will need to research a variety of variables, formulas, and components. Again, the emphasis in this project task is on explaining your methodology as if you attempted to instruct someone unfamiliar with the aerodynamic details and relationships. Therefore, make sure to detail all assumptions, all formulas used, and all steps that were taken. The following will give you some starting points for your search and consideration. 1. Assumptions and conditions: o Assumed atmospheric conditions o Calculated dynamic pressure (second column; based on the assumed atmospheric conditions and KTAS) 2. Necessary aircraft information: o Wing size and configuration (e.g., AR & efficiency factor - if you can't find an efficiency factor for your aircraft, you can make an assumption [i.e., pick a value] somewhere between 0.75 and 0.85) o Weight (should, of course, fall between MTOW and empty weight of your aircraft) o Airfoil information (e.g., CLmax from last module & CDP - if you can't find the CDP for your entire aircraft, you can utilize the minimum drag for your airfoil and add a value of 0.02, which will account for the parasite drag of your aircraft's fuselage) or if you are still having trouble, just use a Cdp of .021 which is a common Cdp. 3. Required formula (for inputs see the formula summary ) 4. Resources and Inputs page) o Dynamic pressure o Lift equation (two forms: one solved for stall speed and the other solved for required CL) o Drag coefficients (CDi & CD) o Application of coefficients to find actual forces (Dp, Di, Dt) o Possibly wing geometry conversions (e.g., wingspan and area into AR or wingspan and average chord into AR) 5. Do not forget to create the diagram. Once created, utilize your derived table and diagram data to answer the following associated questions: A. What are the minimum drag parameters for your aircraft? o Minimum drag value D(min) o Speed VD(min) at which minimum drag occurs o Relationship between Dp and Di at D(min) B. What are the maximum lift to drag ratio CL/CD parameters for your aircraft? o (CL/CD)max value o Speed at which (CL/CD)max occurs C. Compare answers in A. and B. and comment on the findings. D. Explain which of your derived values will allow glide performance predictions for your aircraft and quantify best glide conditions with specific values. Page 2 of 2