1. David Childers March 27, 2008 Final Slides for: Center of Mass Structures Costs AAE 450 Spring 2008

2. 1.Preliminary Design 1.Center of Mass over time 1.1 size fits all-No size difference for each payload 2.Scaled down Vanguard 1.Linearly related to Tsohas Rocket for burn rates and masses 3.Reference point bottom of Vehicle 2.Final Design 1.Center of Mass for full and empty stages 2.Reference point top of vehicle 3.Both 1.Point Mass System 2.Axisymmetric 1.Masses located on body axis Center of Mass AAE 450 Spring 20081 Structures

3. 1.Include Material, Rolling, Rivets, Welding 1.Manufacturing 1.Rolling for just 3 hrs/sheet-No major difference between materials 2.Material costs for non-space grade Aluminum 3.Results in Cost in low $100,000’s 2.Tanks added 1.Original price of Al: $2.30/kg, New price: $13.23/kg 2.Tanks alone priced at several $100,000’s if not millions for large volumes 3.Manufacturing moved to include non-tank components 4.Results jumped into millions Structure Cost Process AAE 450 Spring 20082 Structures

4. Center of Mass Structures Assumptions Point Mass System Symmetric about body axis All masses are centered Top of vehicle is reference Stage Numbered bottom to top Cm of third stage moves down when empty Result of Engine Mass: M engine > M payload 200g1kg5kg Stage: Full/Empty145% (m)115% (m)125% (m) 1: Full5.2843.9147.433 1: Empty3.5452.6475.334 2: Full2.5061.8402.419 2: Empty2.0111.4211.986 3: Full.6310.6410.499 3: Empty0..7140.7500.693 3AAE 450 Spring 2008

5. Cost Breakdown  Manufacturing  Welding  $150/hr  Times:  Al=0.6m/hr  Stl=0.65m/hr  Ti=0.325m/hr  Rivets  1 rivet/6in (1r/0.152m)  $0.73/rivet  0.049 hr/rivet  $52/hr  Manufacturing cont.  Other  $70/hr for 5 hrs/sheet  Ti 5.5 times longer than Al or Steel  Performed for:  Nose cone, Skirts, Skin between tanks, etc.  Material  Rate:  Al=$13.23/kg (Space grade)  Stl=$0.23/kg  Ti=$88.91/kg Structures 4AAE 450 Spring 2008

6. Tanks Cost Structures  ATK Values  Best fit line from Excel using values acquired from ATK  y = 157169Ln(x) + 714253,  where x=volume  10% Discount for multiple tanks  Alternate Approach  Spincraft Values  Labor=$150/hr  Al &Stl: 26 wks (40hrs/wk)  Ti: 52 wks  Not used because of fixed rates  Same price no matter size of tank Figure by David Childers 5AAE 450 Spring 2008 Cost Breakdown

7. Payload TanksManufacturing Material 200g $2,275,400$38,419 $3,755 1kg $1,971,500$33,525 $2,490 5kg $2,879,100$48,296 $7,795 Structure Cost Breakdown Payload Welding Rivets Other 200g $4,345$374$33,700 1kg $3,798$327$29,400 5kg $5,797$499$42,000 Manufacturing Other Manufacturing includes non-tank components, rolling, drilling, forming, etc. AAE 450 Spring 2008 Structures 6

8. References Structures  Paul Morissette, Gilchrist Metal Fabrication  Walter Tam of ATK Space Systems, Inc. (PSI Operations), http://www.psi-pci.com/.  Mike Murphy, Spincraft http://www.spincraft.net/aerospace.htm.  Mark Sutton, G.E.  Cost Considerations in using Titanium, Green, E. A., Coulon, J. F. Lockheed-California Company, Burbank, California v AlAA Paper.  http://www.metalprices.com/  TitaniumJoe.com  Youngstown Tool & Die Co.  RobotMarketplace.com  Tsohas, J., “AAE 450 Spacecraft Design Spring 2008: Guest Lecture Space Launch Vehicle Design”, 2008 7AAE 450 Spring 2008