A “Back of the Envelope” Look at Space Launch Vehicle Costs by Chris Y. Taylor Jupiter Research & Development 2004 AIAA Houston ATS NASA/JSC April 16,

Estimate of Costs for a New Economical Space Launch Vehicle Cargo to LEO Current Technology Expendable Liquid Fuel

C = R Γ C = specific cost ($/lb.) = Launch Cost/Payload Mass R= structure ratio = Structure Mass/Payload Mass Γ= structure cost ($/lb.) = Launch Cost/Structure Mass

Physics & Technology R= structure ratio = Structure Mass/Payload Mass Vehicle R (to LEO) Atlas V 4002 Proton M2.2 Ariane 55.2 Space Shuttle12 Assume R=2 Economics & Management Γ= structure cost ($/lb.) = Launch Cost/Structure Mass C = R Γ

Γ = Γ launch + (Γ nr /a) Γ= structure cost ($/lb.) = Launch Cost/Structure Mass Γ launch = recurring costs Γ nr = non-recurring costs a= amortization factor  flight rate

Γ launch = Γ vehicle + Γ ops + Γ risk + Γ propellant Γ vehicle = Cost of Vehicle Hardware Γ ops = Cost of Operations Γ risk = Cost of Risk Γ propellant = Cost of Propellant

Γ vehicle = f C hardware f= fraction of vehicle expended = 1 (completely expendable) C hardware = cost of hardware ($/lb) $1100 < C hardware <$2300 $1100 < Γ vehicle < $2300

Γ ops = L C labor L= labor intensity (manhours/lb) = Total Labor Hours / Structure Mass 1 < L < 20 (for current launchers) C labor = cost of labor ($/manhour) = $100 $100 < Γ ops < $2000

Γ risk ≈ P fail [C payload /R + (1-f) C hardware ] P fail = probability of failure 0.02 < P fail < 0.05 C payload = cost of payload ($/lb) = payload cost/payload mass ≈ $10,000 R = 2, f = 1 $100 < Γ risk < $250 not including indirect costs

Γ propellant = q C propellant q = Propellant Mass/Structure Mass = R[η/(1-η)] = 18 (assuming R=2, η=0.9) $0.1 < C propellant <$0.25 $1.8 < Γ propellant <$4.5

Launch Costs C = R Γ: If you want C < $1000/lb. and R=2, then Γ must be < $500

Reducing Γ vehicle Γ vehicle = f C hardware Reusable (reduce f) Big Dumb Booster (reduce C hardware )

Reducing Γ ops Γ ops = L C labor Aircraft-like Ops (0.001 < L < 0.01) New Technology Needed SSTO Increased Development Cost

Γ = Γ launch + (Γ nr /a) Γ nr = non-recurring costs $20,000 < Γ nr < $120,000 (assuming R&D only) a= amortization factor  flight rate = 27 (10 yr. payback, 4 yr. r&d, flight rate of 27/6 yr, 0% interest & inflation) $750 < (Γ nr /a)< $4500

Launch Costs

Reducing (Γ nr /a) Reduce Γ nr design for min. Γ nr off the shelf evolutionary cost sharing

Reducing (Γ nr /a) Increase a on orbit assembly cluster vehicles new markets

Selected Bibliography Griffen M.D. and Claybaugh, W.R., “The Cost of Access to Space”, JBIS vol. 47 pp , 1994 Whitehead, J.C., “Launch Vehicle Cost: A Low Tech Analysis”, AIAA paper , 2000 Kalitventzeff, B., “Various Optimization Methods for Preliminary Cost and Mass Distribution Assessment for Multistage Rocket Vehicles”, JBIS vol. 20, pp , 1965 Wertz, J.R., “Economic Model of Reusable vs. Expendable Launch Vehicles”, presented IAF Congress, Reo de Janeiro, Brazil, Oct. 2-6, 2000 Worden, S., “Perspectives on Space Future”, presented 2003 NIAC meeting, Nov. 6, 2003, /library/fellows_mtg/nov03_mtg/pdf/Worden_Simon.pdf Griffen, M.D., “Heavy Lift Launch for Lunar Exploration”, presented U. of Wisconsin, Nov. 9, 2001, Chang, I.S., “Overview of World Space Launches”, Journal of Prop. and Power, Vol. 16, No. 5, pp , Sept.-Oct Claybaugh, W. R., Economics of Space Transportation AIAA Short Course, 2002 World Space Congress, Houston TX Foust, J., “Is There a Business Case for RLVs?”, The Space Review, Sept. 2, 2003,