Cost Estimating
Detailed Design Checklist
Life Cycle Cost
DT&E Cost
Airframe Development Labor Rates Testing
Production Cost
Web Resources
NASA Image
MAE 155A
Detailed Design Checklist
The detailed design phase of aerospace vehicle development includes many of the systems that enable the vehicle to complete its mission.
Power Thermal Communications Radar Cross Section (RCS) Noise
Avionics Crashworthiness Production and Quality Control Maintenance and Support Ground Handling
Systems engineering principals are useful to manage the many details that are associated with the development of complex aerospace vehicles.
Systems Engineering Handbook, SP-2007-6105, NASA Headquarters, Dec. 2007.
MAE 155A
Life Cycle Costs
A new product design must consider its entire cradle-to-grave life cycle existence.
BOL = Beginning of Life MOL = Middle of Life EOL = End of Life
Product EOL will become a more important design consideration as efforts are made to promote recycling and reuse.
Niemann, J., Tichkiewitch, S., Westkamper, E., Design for Sustainable Product Life Cycles, Springer-Verlag, 2009.
MAE 155A
Life Cycle Cost Elements
The Life Cycle Cost (LCC) associated with aerospace vehicle design is roughly broken into four elements:
Research Development, Test, and Evaluation (DT&E) Acquisition and Production Operations and Maintenance (O&M)
O&M is sometimes called Operations and Support (O&S)
Research + DT&E = RDT&E
MAE 155A
DT&E Costs (Aircraft)
DT&E Labor for airframe development is estimated from:
E = 4.86 W 0.777 S 0.894 Q 0.163
E =engineering labor (hrs) W =empty weight (lb) S = max speed (nmi/hr) Q =number of flight test and/or production aircraft
DT&E Development support cost includes test fixtures and parts:
D = 66 W 0.63 S 1.3
D =development cost ($ c1998)
Flight Test Operations are part of DT&E:
F =1852 W 0.325 S 0.822 Q 1.21 D
F = flight test ops cost ($ c1998) Q D = number of development aircraft
MAE 155A
Production Costs (Aircraft)
Tooling Labor:
T = total tooling labor (hrs) W =empty weight (lb) S = max speed (nmi/hr) Q =number of flight test and/or production aircraft
T =5.99 W 0.777 S 0.696 Q 0.263
Manufacturing Labor:
L = 7.37 W 0.82 S 0.484 Q 0.641
Quality Control:
QC =
L = total manufacturing labor (hrs)
0.076L cargo/transport aircraft 0.13L other
QC =quality control labor (hrs)
Material and Equipment:
M = 16.39 W 0.921 S 0.621 Q 0.799
MAE 155A
M = manufacturing cost ($ c1998)
Labor Rates and Project Costs
Project costs include both direct and indirect costs.
Materials, supplies, and labor used in a project are called direct costs.
Accounting factors are introduced to cover indirect costs.
Fringe Benefits = payroll taxes, medical insurance, vacation, coffee Overhead = office space lease, electricity, computers, telephone General & Administrative (G&A) = executive salary, marketing, admin staff Profit = more money for the executives
Labor rate terminology:
Unloaded hourly rate = how much you make (before deductions) Loaded hourly rate = how much the company charges for your work
MAE 155A
Example Cost Estimate
Labor = (unloaded hourly rate)*(number of hours)
($28/hr)*(1 hour) = $28
Fringe Benefits = (fringe factor)*(labor)
(0.5)*($28) = $14
Overhead = (overhead factor)*(fringe benefits + labor)
(0.5)*($14 + $28) = $21
G&A = (g&a factor)*(direct material costs + overhead + fringe + labor)
(0.15)*($0 + $21 + $14 + $28) = $10
Profit = (profit factor)*(g&a + direct mat'l + overhead + fringe + labor)
(0.05)*($10 + $0 + $21 + $14 + $28) = $4
Total Cost = profit + g&a + direct mat'l + overhead + fringe + labor
$4 + $10 + $21 + $14 + $28 = $77 Unloaded Rate = $28/hr Loaded Rate = $77/hr
MAE 155A 8
MAE155B Project Budget
How much should you charge for your work in MAE155B?
Four member team with each student spending 10 hours/week. Assume material costs equivalent to the course fee.
Labor Hours = (4 students)*(10 hrs/week/student)*(10 weeks) = 400 hours Direct Material Cost = (4 students)*($50/student) = $200
Using rate factors from previous slide, the Total Project Cost estimate is $30,670.
MAE 155A
Cost Estimating Web Resource
NASA Johnson Space Center (JSC) has developed a website for cost estimating of aerospace vehicles.
http://cost.jsc.nasa.gov/index.htm
Advanced Missions Cost Model Aircraft Turbine Engine Cost Model Airframe Cost Model COCOMO Software Cost Model Cost Estimating Guidelines Cost Spreading Calculator DSN Cost Estimating Cost Model
Expendable Launch Vehicles Intl. Expendable Launch Vehicles US Inflation Calculators Learning Curve Calculator Mission Operations Cost Model Space Operations Cost Model (SOCM) Spacecraft/Vehicle Level Cost Model
MAE 155A
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