Propulsion QDR #2 AAE451 – Team 3 November 20, 2003 Brian Chesko Brian Hronchek Ted Light Doug Mousseau Brent Robbins Emil Tchilian

3 Aircraft Walk Around Low wing – Clark Y Tricycle Gear Conventional Tail – NACA 0012 Pusher Wing Span ~ 14.6 ft A/C Length = 10 ft Internal Pod

4 Introduction Compare 2 blade propeller to 4 blade propeller with updated code. Do analysis of weight difference between using 2 and 4 blade propeller Pick propeller

Diameter Pitch Diameter Pitch hp Blade Comparison Integrated 4-blade Kappa Code Updated Blade Geometry Cruise Condition 2-Bladed Propellers 4-Bladed Propellers

6 Blade Comparison 4 blades2 blades 16x718x720x5 Cruise Efficiency Cruise RPM Cruise Power [hp] Max Thrust Cruise [lb]

7 Deflection at Tip of Engine Mount Where Thrust = (lbf) L = Length (in) E = Young’s Modulus (psi) I = Moment of Inertia (in 4 ) Assumptions: Small Deflections Safety Factor = 1.5 Rectangular Spruce Beam Current Known Values: Thrust max = 25 lbf L 4-blade = 8 in L 2-blade = 9 in h = 1 in t = varying to get desired deflection Ref. Gere pg. 892 L (in) Thrust (lbf) Moment of inertia of rectangular beam: I (in 4 ) = (t)(h 3 )/12 δ tip (in)=(Thrust)(S.F.)(L 3 )/(3EI)

8 Deflection at Tip versus Weight Assuming 1% Deflection: 2 blade beam weight ~ 0.1 lbf 4 blade beam weight ~ 0.07 lbf Propeller Weight (estimated from density and volumes): 2 blade ~ 0.1 lbf 4 blade ~ 0.2 lbf 4 blade weight penalty ~.07 lbf 2 blade 4 blade

9 Chosen Propeller 4-blades Zinger 16X7 Wood Pusher Propeller –16 inches in diameter with 7 inch pitch –4 blades Ref.

10 Questions?