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18-1 Sarah page Edwin Kumar peter Schneider rick prasad. 154A Aircraft Design. Changing the Specs. Other STOL Planes . Picture of Mountain Goat STOL. Mountain Goal STOL. Max Gross Weight: 2500 lbs Wing Span: 35.5 ft Wing Area: 188 sq ft. Katmai STOL Plane with Canard.
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18-1Sarah page Edwin Kumarpeter Schneider rick prasad 154A Aircraft Design
Other STOL Planes Picture of Mountain Goat STOL Mountain Goal STOL Max Gross Weight: 2500 lbs Wing Span: 35.5 ft Wing Area: 188 sq ft Katmai STOL Plane with Canard Max Gross Weight: 2950 lbs Stall Speed: 40 mph Takeoff Distance: 383 ft R/C: 1380 rpm • http://www.katmai-260se.com/
Airfoil Selection WING NACA 1412 Airfoil at 5° angle of attack Lift Curve Slope Drag Polar
Airfoil Selection CANARD NACA 23018 Lift Curve Slope Drag Polar
Airfoil Selection TAIL NACA 0009 Lift Curve Slope Drag Polar
Drag Calculations Induced Drag Parasite Drag
Thrust Required / Available 147 fps
Lift to Drag Ratios 104 fps 142 fps 182 fps
Designing a Propeller 250HP @ 2600 RPM 285HP @ 2700 RPM 210HP @ 2700 RPM
Propeller Design for Takeoff Variable Pitch Propeller Required Thrust versus Velocity for a 285 HP engine with a 15 degree blade angle
Range • Bruguet Range Equation • Our L/D ratio is less than comparable aircrafts • This is due to trade-offs between STOL and other performance aspects • Cruise Range: • ~1037 statute miles @ 160 mph
Range • Maximizing Range • This happens at the maximum L/D ratio possible • L/D)max occurs at the minimum thrust setting • Historical trends show that our L/D)max should occur at around 12. • This is a good check for our calculations • L/D)max turns out to be ~12.7 • Maximum Range: • ~1581 statute miles @ 101 mph
Endurance • Found using a different form of Berguet Range equation • Density is a factor in this equation • The aircraft we based ours upon, the Peterson Katmai has an endurance of 13.6 hour @ 69 mph
Weight Calculations • Initial estimates done with mission segment method • Our mission profile is that of a “contraband runner” • No significant loiter time • Estimates done using Berquet range equation • Concerns arose about our fuel fraction • Topped out at 17% early in design process • Estimating using this method depends on expected range • We failed to account for reduced range
Weight Calculations • Due to the similarities between our aircraft and Cessna 172, we used the Cessna weight estimations • The engine, wing, and fuel/fuel system accounted for most of the plane’s weight
Final Weigh Estimates Gross Takeoff Weight: 2631.81 lbs