PROPULSION PDR 2 AAE 451 TEAM 4 Jared Hutter, Andrew Faust, Matt Bagg, Tony Bradford, Arun Padmanabhan, Gerald Lo, Kelvin Seah November 11, 2003

CONCEPT REVIEW Empennage High Wing Twin Booms Twin Engine Avionics Pod S = 47.8 ft2 b = 15.5 ft, c = 3.1 ft AR = 5 Twin Booms 3 ft apart; 7.3 ft from Wing MAC to HT MAC Twin Engine 1.8 HP each Avionics Pod 20 lb; can be positioned front or aft depending on requirements Empennage Horizontal and Vertical Tails sized using modified Class 1 Approach (per D & C QDR 1)

OVERVIEW Engine Selection & Endurance Propeller Selection, Analysis & Choice Twin Engine Performance Follow-Up Actions

Propeller Efficiency of 45% used CONSTRAINT DIAGRAM showing only relevant constraints for single engine operation Propeller Efficiency of 45% used

ROADMAP TO ENGINE SELECTION Calculations based on single-engine flight From the Constraint Analysis, Power Loading, W/P = 46 lbf / SHP From Current Weight Estimate, Gross Take-Off Weight, WTO = 54.5 lbf Total Required Power = 1.2 HP

ENGINE CHOICE Engine Choice: Saito FA-100 Specifications: Weight: 20.8 oz Bore: 29.0 mm Stroke: 26.0 mm Displacement: 1.0 cu. in. Practical RPM: 2,100 - 9,500 Power: 1.8 BHP @ ~9200 RPM Fuel Consumption Rate: 1 oz/min $279.99 at maximum RPM Source: http://www.saitoengines.com

DRAG ANALYSIS & REQUIRED THRUST Span efficiency, e 0.6 Aspect Ratio, AR 5 Lift Coefficient, CL 1.03 Induced Drag Coefficient, CDi 0.112 Parasitic Drag Coefficient, CD0 0.06 Drag Coefficient, CD = CD0 + CDi 0.172 Wing Area, S 47.08 ft2 Velocity = 1.2 Vstall = 1.2 28 ft/sec = 33.6 ft/sec Density, ρ = 0.002377 slug/ft3 Drag = 10.4 lbf

DRAG ANALYSIS & REQUIRED THRUST (continued) Drag = 10.4 lbf Flight Path Angle,  = 0.5 Weight = 54.5 lbf Thrust = Drag + Weight*sin() = 10.9 lbf L T V D  W 

ENDURANCE CALCULATIONS Fuel Consumption @ Max. RPM = 1 ounce per minute Total Endurance Time 30 min. Warm-up, Take-off, & Climb 5 min. max. RPM Landing & Descent 5 min. ~ half RPM Cruise & Loiter 20 min. ~ 90% RPM Minimum Fuel Required = 25.5 ounces/engine Fuel Reserve & Inert Fuel = 2.5 ounces/engine Total Fuel Requirement = 56 fluid ounces = 2.92 lbs

ROADMAP TO PROPELLER SELECTION Varied propeller diameter and pitch to match engine  propeller  airframe Matched manufacturer’s HP @ within RPM range Matched thrust and velocity requirements from constraint analysis and mission requirements.

PROPELLER ANALYSIS Gold.m was used to produce all results Key in Inputs The desired blade diameter and pitch Manufacturer specified RPM range (9000 to 9500 RPM) Desired operating flight velocity (33.6 ft/s) Re-iterate using Outputs Horsepower and Thrust Final desired Outputs 1.8 HP within RPM envelope  11.1 lbf of thrust

PROPELLER ANALYSIS

PROPELLER ANALYSIS 9400 RPM

PROPELLER ANALYSIS ηp = 0.379

PROPELLER CHOICE Diameter: 17” Pitch: 5” Theoretical Chord: 0.765” RPM: 9,400 rev/min Power: 1.79 HP Advance Ratio: 0.1514 rev-1 Power Coefficient: 0.0188 Thrust Coefficient: 0.0470 Efficiency: 37.9%

PROPELLER ANALYSIS

PROPELLER ANALYSIS

PROPELLER ANALYSIS

CONSTRAINT DIAGRAM single engine operation Propeller Efficiency of 37.9% used  1.4 HP engine required Engine meets requirements  Analyze twin engine performance

Twin Engine cruise performance Both engines turning @ 8250 rev/min Cruise velocity 60 ft/sec Efficiency 64.1 % Torque 0.788 ft-lbs Advance ratio 0.308

Twin Engine maximum performance Both engines turning @ 9500 rev/min Maximum velocity 70 ft/sec Efficiency 64.6 % Torque 0.765 ft-lbs Advance ratio 0.312

FOLLOW-UP ACTIONS Study actual propeller geometry to improve accuracy of results Contact engine and propeller manufacturers Determine fuel feed system

QUESTIONS?

APPENDIX PROPELLER COMPARISON Different propellers compared End results checked with availability 17” x 6” @ 8800 RPM 17.5” x 5” @ 9000 RPM 17” x 5” @ 9400 RPM HP required 1.790 HP 1.745 HP 1.780 HP Thrust Produced 11.061 lbf 11.064 lbf 11.054 lbf Propeller Efficiency 37.74% 38.74% 37.93%