Launch Propulsion: SMC/LR Perspectives Presented to Launch Propulsion Workshop Caltech Pasadena, CA Presented by Lt Col Toby Cavallari Chief Engineer Launch and Range Systems Directorate Space and Missile Systems Center 23 March 2011

ELV History (1958 – Present) In past 50 years, propulsion enabled ballistic and spacelift capabilities Powered first US ICBMs Evolved into launch vehicle systems, opening the door to space Continued with improvements in performance, reliability, and operability However, more than 40% of all historical launch vehicle failures caused by propulsion subsystem malfunctions (#1 contributor) Drawing courtesy of Boeing

Historical USAF Development & Industrial Base More than 50 years, USAF has been a key player in rocket development Today, only several U.S. companies are active

EELV Families Two families of launch vehicles (Atlas V and Delta IV) (401) (5XX Series) Delta IV (Med) Atlas V Family GTO Capability (lbs) 8/02 7/03 (4XX Series) Delta IV (Med+ 4 series) (Med+ 5 series) (Heavy) 3/03 11/02 12/04 Delta IV Family 5,000 10,000 15,000 20,000 25,000 30,000 IOC Atlas V (Heavy) PWR RS-68 Engine Russian RD-180 Engine RL10-A-2 Engine RL10B-2 GEM-60 SRB

Current EELV Propulsion Environment Escalating engine cost growth Must ensure engine availability for EELV until 2030 Supplier obsolescence Reliance on foreign suppliers for EELV mission assurance and sustainment Payload mass-to-orbit expected to continue on an upward trend Declining U.S. industry capability in engine development and production Some specific concerns: EELV Upper Stage Engines: 50-year-old craftsman-based manufacturing Currently flying at reduced confidence margins Running at twice original engine chamber pressure Requiring highly selective screening per USG standards Increased mission assurance costs No further growth opportunity without major redesign Kerosene Booster Engine: DoD reliance on Russian designed and built engine Limiting opportunity for technology transfer to new U.S. engine effort Also, ITAR restricts U.S. technology transfer into RD-180 program

Chamber Pressure (psia) RL10 Engines LOX/LH2 engine built by Pratt-Whitney Rocketdyne Expander cycle 1st RL10 flight in 1963 (RL10A-3 on Centaur) RL10A-4-2 and RL10B-2 first flown in 2002 Atlas V and Delta IV 2nd stage engines More than 40% component commonality between Delta and Atlas RL10 variants RL10A-4-2 (Atlas V) RL10A-4-2 (Atlas V) RL10B-2 (Delta IV) Thrust, vac (lbf) 22,300 24,750 Chamber Pressure (psia) 610 640 Isp, vac (sec) 450.5 464 MR 5.5 6.0 Expansion Ratio 84 285 RL10B-2 (Delta IV)

Upper Stage Engine History & Future Paths Qual. Year RL10A-1 15k lbf Pc=300 psia Isp = 422 s 1961 1963 1967 1991 1998 1999 2000 RL10A-3 Isp = 427 s 1966 1985 1994 A-1 A-3 A-3-1 A-3-3A A-4 A-4-1 B-2 A-4-2 A-3-3 A-4-1A RL10A-3-3A 16.5k lbf Pc=475 psia Isp = 444.4 s RL10B-2 24.7k lbf Pc=640 psia Isp = 464 s RL10A-4-2 22.3k lbf Pc=610 psia Isp = 451 s (Delta IV) (Atlas V) Model Possible Upper Stage Engine Paths Converting existing RL10B-2 inventory No further growth opportunity without major redesign Fly RL10C on Atlas V RL10C RL10A & RL10B-2 Next Generation Engine (NGE) True common, new upper stage engine Greater designed-in reliability/performance margins Fly on both Atlas V and Delta IV

Upper Stage Next Generation Engine (NGE) Objectives Modern manufacturing techniques Greater designed-in reliability and performance margins More sustainable Lower life cycle cost Achieve a truly common LOX/Hydrogen upper stage engine Incorporates National Security Space & NASA requirements Interagency partnership opportunity Captures emerging commercial needs Creates open competition Bolster U.S. liquid propulsion industrial base capability Leverage advanced design tools matured by AFRL/NASA technology investment e.g. AFRL Upper Stage Engine Technology (USET) SMC/Aerospace and NASA currently assessing benefits of using the NGE for Evolved Expendable Launch Vehicle (EELV) missions NASA’s Cryogenic Propulsion Stage for space exploration

Potential Partnership Areas Opportunities for joint propulsion development programs Overcome emerging National Security Space challenges and declining budgets Lay groundwork for interagency cooperation and commercial partnerships Take advantage of NASA’s commitment to advanced tech development and emerging commercial needs National Propulsion Strategy for upper stage engine (e.g. NGE) and high- thrust kerosene booster engine Common engine - not common vehicle architectures Improved funding stability Accelerated development schedule Shared testing and ground certification costs Optimal use of national test facilities Revitalize declining industrial base capability New engine has many cross-cutting mission benefits & capabilities Military, civil, and commercial

Backup Charts

Chamber Pressure (psia) RD-180 Engine Atlas V Common Core Booster (first stage) engine LOX/kerosene engine built by NPO Energomash, Russia Oxygen-Rich Staged Combustion (ORSC) cycle First flown in 2002 Full Power Level (100% PL) Min. Power Level (47% PL) Thrust, vac (lbf) 933,400 438,700 Thrust, sea level (lbf) 860,200 365,500 Chamber Pressure (psia) 3722 1755 Isp, vac (sec) 339.3 335.5 Isp, sea level (sec) 312.7 279.5 MR 2.72 (+/- 7%) Expansion Ratio 36.87

Chamber Pressure (psia) RS-68 Engine Delta IV Common Booster Core (CBC) engine LOX/LH2 engine built by Pratt & Whitney Rocketdyne Largest LOX/LH2 engine Used existing technologies to minimize cost and risk Gas Generator (GG) cycle First flown in 2002 RS-68A upgrade certification underway Full Power Level (102% PL) Min. Power Level (57% PL) Thrust, vac (lbf) 751,000 432,000 Thrust, sea level (lbf) 656,000 337,000 Chamber Pressure (psia) 1420 815 Isp, vac (sec) 409 Isp, sea level (sec) 357 MR 6.0 Expansion Ratio 21.6

Atlas V Solid Rocket Booster (SRB) Strap-On Solid Motors Atlas V Solid Rocket Booster (SRB) Delta IV GEM-60 Atlas V (500 Series) (0-5 SRBs) (400 Series) (0-3 SRBs) SRB GEM-60 SRB Characteristics Diameter (in) 62 Length (ft) 67 Gross Weight (lb) 102,396 Burn Time (sec) 88 Total Impulse, Vacuum (lbf-sec) 26,190,000 Isp, Vacuum (sec) 279.3 Average Thrust, Vacuum (lbf) 270,420 Max Thrust, Vacuum (lbf) 380,000 MEOP (psi) 1600 GEM-60 Characteristics Diameter (in) 60 Length (ft) 53 Gross Weight (lb) 74,700 Burn Time (sec) 90.8 Total Impulse, Vacuum (lbf-sec) 17,950,000 Isp, Vacuum (sec) 274 Average Thrust, Vacuum (lbf) 197,540 Max Thrust, Vacuum (lbf) 300,000 MEOP (psi) 1294