Propulsion

1. Propulsion Chuck Zakrwski NASA/GSFC Code 597 August 16-17, 2005

2. Lunar Reconnaissance Orbiter (LRO)Propulsion SystemDocument Tree • Level 2 • 431-RQMT-000004 LRO Mission Requirements Document • 431-PLAN-000131 Lunar Reconnaissance Orbiter Spacecraft Performance Assurance Implementation Plan • 431-OPS-000042 Lunar Reconnaissance Orbiter Concept and Operations Document • 431-ICD-000008 Lunar Reconnaissance Orbiter Electrical Systems Interface Control Document • 431-SPEC-000091 Lunar Reconnaissance Orbiter General Thermal Subsystem Specification • 431-RQMT-000012 Lunar Reconnaissance Orbiter Mechanical Environments and Verification Requirements • Level 3 • 431-SOW-00017 Lunar Reconnaissance Orbiter Propulsion Subsystem Statement of Work and Specification • 431-LIST-000135 Lunar Reconnaissance Orbiter Propulsion Subsystem Deliverable Items List and Schedule • 431-RQMT-000045 Lunar Reconnaissance Orbiter Radiation Requirements • 431-RQMT-000092 Lunar Reconnaissance Orbiter Thermal Math Model Requirements • Level 4 • 431-SPEC-000136 Lunar Reconnaissance Orbiter Propellant Tank Specification • 431-ICD-(TBD) Lunar Reconnaissance Orbiter Propulsion Subsystem Mechanical Interface Control Drawing

3. Lunar Reconnaissance Orbiter (LRO)Propulsion SystemLevel 2 Flow Down KeyRequirements

4. Lunar Reconnaissance Orbiter (LRO)Propulsion SystemLevel 2 Flow Down KeyRequirements

5. Lunar Reconnaissance Orbiter (LRO)Propulsion SystemLevel 2 Flow Down KeyRequirements

6. R R R R Lunar Reconnaissance Orbiter (LRO)Propulsion SystemBlock Diagram Pressurant Tank (Helium) P High Pressure Panel Pressure Transducer Fill and Drain Valve Pyrotechnic Valve (Normally Closed) Filter Latch Valve Regulator P P Fill/Drain Valve Panel Cylindrical Propellant Tank (PMD) Propellant Management Device 5 lbf Thruster 20 lbf Thruster P Low Pressure Panel Dual Thruster Module #1 Dual Thruster Module #2 Dual Thruster Module #3 Dual Thruster Module #4

7. Lunar Reconnaissance Orbiter (LRO)Propulsion SystemPreliminary Verification Approach • Components • All components, with possible exception propellant tank, are expected to have been previously qualified • Nutation time constant constraints may require tank re-qualification • Acceptance testing required of all components (mechanical, thermal, and electrical) • Thruster acceptance testing to include ‘hot-fire” tests which encompass worst case thermal environments • Propulsion Module • All welded system with NDE of all welds • Functional tests at pre- environmental, post environmental and launch site include: Proof, System Leak, Valve Leak, Electrical Functional, Gas Flow Impedance • Environmental tests options include: • Acoustics, Sine Sweep, Sine Vibration, Thermal Vacuum/Balance • System designed to be “wet” with test fluid for environmental tests • Enable plugs in subsystem to prevent inadvertent operation of all valves and catalyst bed heaters during I&T

8. Lunar Reconnaissance Orbiter (LRO)Propulsion Summary • LRO Propulsion driving requirements are defined • Propulsion functions and delta-V requirements has been established • Preliminary architecture has been identified which will satisfy driving requirements • GSFC acquisition of propellant tank allows interface requirements between subsystems to be defined at appropriate levels • Interfaces between the propulsion system and the following subsystems have been defined at Level 3 and are being developed at Level 4: • Mechanical • Thermal • ACS • Electrical • Power • Propulsion system ready to proceed to contractor selection/award and PDR