Design Group 2

Kat Donovan - Team LeaderAndrew DeBerry

Mike KinderJohn Mack

Jeff NewcampAndrew Prisbell

Nick Schumacher

Conceptual Designfor AME 441Spring 2004

Group 2 – Ducted Design

Overview

• Aircraft Configuration & Design Drivers• Comparison Aircraft• CAD Models• Spreadsheet Decisions

o Airfoil Choiceo Engine Selectiono Weight & Drag Estimateso Static Stability

• Conclusions & Lessons Learned• Design & Build Schedule

Aircraft Configuration (Requirements)

• Powered by electric motor• Carry specified payload• Take-off in < 300 feet on grass• Planform area between 400 in2 & 800 in2

• Radio control system with up to 7 channels

Design Drivers• Maximize the climb rate

• Maximize the level flight speed

Comparison Aircraft

* Information from http://www.aerospaceweb.org/aircraft/bomber/yb49/† Information from http://www.aerospaceweb.org/aircraft/bomber/b2/‡ Information from Design and Construction of a Remote Piloted Flying Wing, May 2, 1994

CAD Models

Electronics Box Battery Pack (x2) Circuit Card

Servo GPS Receiver Modem

CAD Models - Dimensions

• NACA 6412o Low Reynolds

Number airfoilo t/c ratio large

enough to house internal electronics

Airfoil Choice

Sample Lift Estimation

http://www.grc.nasa.gov/WWW/K-12/airplane/foil2.html

Engine Selection: Astro Cobalt 15

9 ozGear Motor Weight

Data from www.astroflight.com

1/4 inchProp Shaft Diameter

5/32 inchMotor Shaft Diameter

1.3 inchesMotor Diameter

3.3 inchesGear Motor Length

400 wattsMaximum Continuous Power

25 ampsMaximum Continuous Current

2 ampsNo Load Currrent

8 to 12 voltsVoltage Range

2.17 in-oz /ampGeared Torque

0.91 in-oz /ampMotor Torque/amp

652 rpm/voltGeared Motor Speed

1488 rpm/voltMotor Speed

Ball BearingsBearings

Sm CobaltMagnet Type

0.069 ohmsArmature Resistance

7 turnsArmature Winding

2.38 to 1Gear Ratio

05 GearedName

p/n 615GModel No.

• Electric, brushless motor• Runs off 16-cell

rechargeable battery pack

Power Estimate

Thrust Estimates

Thrust, Drag, Estimates

Weight & Drag Estimates

8.36Total:

0.65Main Battery

0.08Speed Controller

1.5Electronics Box

0.5GPS & Transmitter

0.25Receiver & Battery

0.32Servo (x4)

0.06Propeller

0.56Engine (Cobalt 15)

0.6Landing Gear

3.84Structure

Aircraft Weights (lbs)

Static Stability

2.9108840.97m.a.c. (ft)

8.3076920.461538L_ctr (x/L)

Wing Center of Lift

2L (f)

Fuselage Length

Conclusions & Lessons Learned

• Flying wing to maximize rate of climb and level cruise speed

• Ducted fan to increase propeller efficiency• Winglets to reduce drag• Tricycle landing wheels to prevent damage

during landing• At least 24” separation of modem and GPS

to limit interference

Design & Build Schedule

26 February: Present Detailed Design

4 March: Complete Parts List

16 March: Fabrication

6-9 April: Ground Tests

13-22 April: Flight Tests

Group 2: Nick SchumacherAndrew DeBerryAndrew PrisbellJeff NewcampKat DonovanMike KinderJohn Mack

Questions?