Umaine SAE Aero Design

1. David Chandpen (Lead Engineer) Matthew Maberry Travis Cushman Benjamin Waller Zach Veilleux Joseph Travaglini Umaine SAE Aero Design

2. Mission Statement The objective is to design an aircraft that can lift as much weight as possible while observing the available power and aircraft’s length, width, and height requirements. Accurately predicting the lifting capacity of the aircraft is an important part of the exercise, as prediction bonus points often determine the difference in placement between competing teams.

3. Design Parameters Regular Class • The free standing aircraft shall not exceed a maximum combined length, width, and height of 225 inches. • The aircraft may not weigh more than sixty five (65) pounds with payload and fuel. • The use of Fiber-Reinforced Plastic is prohibited. • Powered by a single, unmodified Magnum XLS-61A engine. • Servos must be adequately sized to handle the expected aerodynamic loads during flight.

4. Budget

5. Design Requirements: High lift coefficient for takeoff (wing loading can be higher) Wide AOA with decent Cl Gentle stall entry Low induced drag Minimal Center of Pressure Movement Ease of manufacture High Cl / Cd in our range of speed Airfoil Selections

6. Basic Considerations • Greater camber / higher camber factor will increase lift for any speed, but will reduce speed of flight for any weight • Higher camber leads to greater COP movement as AOA changes, and flow may separate more readily, especially at low Re • Thin airfloils could reduce weight and parasite drag but are harder to support internally, and low speeds are dominated by induced drag. • We want trade-offs to work in our favor more often than not

7. Data (XFLR5)

8. Generation of PolarsNACA 0009

9. Selig S1223

10. ComparisonsExample Data Chart

11. Example Comparison Graphs:

13. Next Steps • The next action will be to review the comparison data and select a few of the airfoils for further testing • XFLR5 can also form 2-D airfoils into wings for basic flow analysis • There are at least as many design choices with wing configuration design as with airfoil selection

14. Thrust Test of Magnum XLS-61A • In order to accurately predict how much lift the aircraft will produce, the amount of thrust our engine can produce is needed. • Thus, a thrust test will be performed. • Data acquired from a strain gauge will provide us with the information we need to calculate how much force the engine produced. • This test will be performed on 4 different propellers.

15. Thrust Test Set-Up Strain Gauge Prop Engine Thrust Force Direction Rigid Support Free Rolling Cart

16. Wind Tunnel Testing • Real-life experimental data is needed in order for us to pick the airfoil that is going to be implemented into our design. • After the 2D flow simulations data from Xlfr5 has been acquired for a number of airfoils, a select few will be chosen to run tests in the wind tunnel. • The data from these tests will determine the final airfoil choice.

17. In order to get to that point, several steps need to be taken. • Safety protocol for operation needs to be made. • Mapping of the flow in the tunnel • Calibration of a rigid test-subject stand -Several strain gauges that will give use values for parameters such as lift, drag, and torques.

18. Wind Tunnel Set-Up Airfoil Wind Direction Fan Strain Gage Rigid Stand

19. Progress Report • Research • Rules • Necessary components • General process • Design choices • Single high-mounted wing • Motor selection • Payload containment system • Cleaned and Organized Crosby 201 • Safety Protocol • Inventory • Wind Tunnel Start-up • Budget • 2D Airfoil Data • Airfoil selections • Spreadsheet of parameters and values compared against each other • Thrust Test Design • Made a tachometer for the set-up