1. DR2 Propulsion PDR I Preliminary Design Review II October 17, 2000 Presented By: Mark Blanton Team DR2 Chris Curtis Loren Garrison Chris Peters Jeff Rodrian

2. DR2 Propulsion PDR I Propulsion PDR II Presentation Content –Aircraft Parameters –Propeller Selection –Motor/Gearbox Selection –Speed Controller Selection –Motor Power Source –Motor/Component Price List

3. DR2 Propulsion PDR I Aircraft Characteristics –Values Required for Motocalc aircraft evaluation –Aerodynamics & Weight Wing Span92.52 inches Wing Area2141.20 square inches Empty Weight98.52 ounces Flight Speeds Takeoff Speed23 ft/s Cruise Speed25ft/s

4. DR2 Propulsion PDR I Propeller Selection –Propeller clearance of the fuselage Propeller Minimum Diameter is 14 inches, hence propeller diameter –Gold.m Analysis vs. Motocalc Analysis Gold.m input includes the flight speed, and motor parameters Gold.m output includes propeller thrust and propeller power based on input Motorcalc input includes aircraft parameters, propeller size, motor, gearbox size, speed controller, and power source Endurance time can be evaluated from Motocalc as well as verification of the power used by the motor and propeller

5. DR2 Propulsion PDR I Propeller Selection –Propeller Pitch Selection Master Airscrew Propellers in Inventory Propeller Pitches available 6, 8, and 10 inch from Tower Hobbies –Propeller Flight Requirements Thrust and Endurance Time –Maximum Thrust Required at Takeoff2.7607 lb –Thrust Required during Cruise0.7624lb –Required Cruise Endurance Time @ 17 ft/s00:12:00minutes

6. DR2 Propulsion PDR I Propeller Selection –Propeller Pitch Evaluation Pitch = 6 inch –Maximum Thrust at takeoff2.4889pounds –Underpowered for takeoff conditions Pitch = 8 inch –Maximum Thrust at takeoff3.2618pounds –Thrust during Cruise1.7937pounds –Endurance Time @ 17 ft/s00:14:57 –Thrust requirement and time requirement met

7. DR2 Propulsion PDR I Propeller Selection –Propeller Pitch Evaluation Pitch = 10 inch –Maximum Thrust at takeoff4.0128pounds –Thrust during Cruise1.545pounds –Endurance Time @ 25 ft/s00:17:44 –Thrust requirement and time requirement met Propeller Selected –Propeller Size of 14 x 10 inch selected because of the thrust advantage and higher endurance time

8. DR2 Propulsion PDR I Propeller Thrust Conditions During Takeoff –Takeoff Conditions Flight Speed23 ft/s RPM of Propeller5831 RPM Max. Thrust Required2.7607pounds Thrust Coefficient0.0964 Integrated Thrust Value4.0128 pounds –Takeoff Conditions exceeded Thrust available is 145% greater than maximum required thrust for liftoff Throttle Setting 100%

9. DR2 Propulsion PDR I Propeller Thrust Conditions During Cruise –Cruise Conditions Flight Speed25 ft/s RPM of Propeller3899 RPM Thrust Required0.7624pounds Thrust Coefficient0.0830 Integrated Thrust Value1.5450 pounds –Cruise Conditions exceeded Thrust available is 200% of minimum required thrust for cruise Throttle Setting 65%

10. DR2 Propulsion PDR I Takeoff C T Plot on the Left T = 4.0128 pounds Cruise C T Plot on the Right T = 1.5450 pounds

11. DR2 Propulsion PDR I Propeller Power Conditions during Takeoff –Takeoff Conditions Flight Speed23ft/s RPM of Propeller5831 RPM Motor Power Available0.6705 hp Power Coefficient0.0458 Propeller Power Required0.3927 hp –Takeoff Conditions Exceeded Excess Power Total is 171% of Propeller Required Power Throttle Setting at 100%

12. DR2 Propulsion PDR I Propeller Power Conditions during Cruise –Takeoff Conditions Flight Speed25 ft/s RPM of Propeller3899RPM Motor Power Available0.6705 hp Power Coefficient0.0458 Propeller Power Required0.1174 hp –Takeoff Conditions Exceeded Excess Power is 571% of Propeller Required Power Higher Efficiency at lower RPM Throttle Setting 65%

13. DR2 Propulsion PDR I Takeoff C P Plot on the Left P = 0.3927 hp Cruise C P Plot on the Right P = 0.1174 hp

14. DR2 Propulsion PDR I Propeller/Motor Gearbox Selection –Based on Engine SelectionAstro25G –Standard GearboxAstro 035-15 Gearbox Characteristics –Gear Ratio 2.38:1 –Manufacturer attaches the gearbox –Weight incorporated with the motor weight

15. DR2 Propulsion PDR I Motor Selection –Selection based on current inventory, historical data point, and Motocalc electric motor evaluations –Comparison Drawn between Astro25G, 40G, and 60G Gear Ratio fixed at 2.38:1 Motocalc Filter set at 30 Amps – To be sure that the amperage is not too high –Verifies the combination of all components –Astro 40G Didn’t meet filter restrictions, passed endurance time with 00:13:23 at 25 ft/s –Astro 60G Passed endurance time with 00:13:28 at 25 ft/s –Astro 25G Passed endurance time with 00:17:44 at 25 ft/s

16. DR2 Propulsion PDR I Motor Characteristics –ManufacturerAstroflight –MotorAstroflight 25G Horsepower0.6705 hp Weight12.5ounces Motor Efficiency0.78 Motor Constant971 RPM/Volt Rated Cell Number10 – 16 cells Aircraft Speed Controller –Astro 204D Characteristics Resistance0.005Ohm Maximum Current50Amps Weight1.1ounces

17. DR2 Propulsion PDR I Aircraft Power Source –Sanyo 1700SCR Number of Cells14 Capacity1.700 A–hr Weight1.89 ounces each –Endurance Requirement Required Endurance Time12 minutes Throttle Setting75% Estimated Endurance Time @ 100% Charge17 minutes 44 seconds Estimated Endurance Time @ 70% Charge12 minutes 24 seconds

18. DR2 Propulsion PDR I Motor Component Price List –Tower Hobbies Price List(Magazine and Online) –Tower Hobbies –Astroflight 25G$ 180.00(In Inventory) –Master AirScrew 14x10 inch propeller$ 5.29 –Astro 035-15 2.38:1 Gearbox$ 0 (attached to motor) –Astro 204D Speed Controller$ 109.00(In Inventory) In Inventory –Sanyo 1700SCR$ 69.86(14 count) –Total Cost $ 75.15 (If batteries not available)

19. DR2 Propulsion PDR I Questions?