1. Propulsion PDR 2 Team Boiler Xpress Michael VanMeter Oneeb Bhutta Matthew Basiletti Ryan Beech October 17, 2000

2. Topics of Discussion  Motor Selection  Pusher propeller considerations  Gearbox Selection  Propeller Selection  Bigger is better  Pusher propeller considerations  Battery Selection

3. Aircraft Dynamics  Power loading constraint W/P = 0.2 lb-s/lb-ft P = 45 ft-lb/s = 0.08 hp

4. System Efficiencies  Propeller (50%)  Historical data  Gearbox (90%)  Conservative side of historical values  Required motor power output P = 100 ft-lb/s = 0.18 hp = 135.6 W

5. Motor Selection  Excess power (margin of safety)  47.5% margin  Equivalent to a constraint of 10 degree climb angle  Resulting power requirement for motor P = 200 W  Adjustable timing for motor reversal due to pusher propeller

6. Model Electronics Corporation Turbo 10 GT  Large gear ratio range  2.0:1 through 9.6:1  High endurance properties  Adjustable timing  Reversible  Economical  $65.00 for motor  $55.00 for gearbox  Uses standard speed controller

7. Propeller Selection  Bigger is better  Larger diameter  Lower RPM  Would like to test several size propellers with wind tunnel setup  Investigating specialized electric flight propellers (shown right)

8. Gearbox Selection  Larger Propeller spinning at a lower RPMs generally gives higher efficiency  Expected gear ratio  6:1 or 7:1  With 14” to 18” propeller

9. Battery Selection  Cells  10 – 1.2Volt/cell  1700 – 2000 mAh  Total endurance  Will meet endurance requirement t = 13.43 min

10. Thank You Questions?