1. Systems Engineering
Implementation
In Launch Vehicle Development
Programs
Timothy T. Chen
Spacecraft & Vehicle Systems Department
Marshall Space Flight Center

2. Launch Vehicle Project Challenges
• Design of a new launch vehicle is a large complex system development
project.
• Its probability of success is often handicapped by:
 Complex requirement development (creep) process.
 Conflicting stakeholders’ expectations that often surfaced late in the
project design cycle.
 Acquisition strategy.
 Inherent nature of technology development risks in the project.
 Complex technical integration & interfaces across major elements.
 High initial non-recurring cost for capital investments
 Often higher than what the stakeholders are willing to tolerate.
 Limited schedule to demonstrate success before the project is in risk of
being cancelled.
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3. Project Manager’s Headaches
• The Project Manager’s challenge is further aggravated when faced with
the following issues:
 Lack of experienced and knowledgeable staff.
 Launch vehicle design projects come once in a couple, to several, decades.
Experienced & seasoned professionals, especially in project management &
systems engineering with proven success in executing projects at the level
of technical complexity, are limited.
 Limited supply chain available from prime contractors to component
suppliers.
 Commercial Off-The-Shelf (COTS) and “Heritage” hardware do not
mean “Plug-n-Play”.
 Iterations and “spiral” design approach can be very costly to the Project
Manager.
 Antiquated in-house processes and procedures
 Do not keep up with the advances in project management & acquisition
practices.
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4. How can System Engineering help?
• The Systems Engineer
 is your technical manager for the Project
 Defines the phases the scope of the total effort
 Establishes the technical baseline and future modifications (upgrades)
 Provides qualified personnel and processes to Systems Engineering &
Integration (SE&I) in all top level system activities
• So, you as Project Manager can focus on other tough problems!
 A juggling act !
Time Scope
Cost
Stakeholders
Communication Project Manager
Quality
Sub-contracts Risk
Contracts Staff/ HR
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5. Systems Engineering Functions
• Engineer the System • Planning and Control • Produce the System
 Requirements  Organizing & Planning  Integrated across
Analysis / Definition /  SEMP, IMP/IMS all systems and
Validation  Requirements components
 Functional Analysis Management  Product Life
& Allocation  Interface Management Cycle
 Synthesis of  Baseline Management  Product
Designs  Integration
 Affordability
 Evaluation of  Verification
 Decision Making
Alternatives  Validation
 Risk Management
 Requirements  Trade Studies  Transition
Verification
 TPMs
 Metrics Management
 Reviews
Drive Technical Solution Technical Management Realize Product

6. Systems Engineering throughout
the Product Life Cycle and at each
Level
MISSION DEFINE CONCEPT CONCEPT PRELIMINARY DETAILED FIRST PRODUCTION OPERATIONS/
ANALYSIS MISSION DEFINITION DEVELOPMENT DEFINITION DEFINITION ARTICLE SUPPORT
DEFINITION REQUIREMENTS
MCR ACR SRR SDR PDR CDR FRR/PRR ORR DR
1 SYSTEM
2 SEGMENT
3 SUBSYSTEM
MAJOR MILESTONES
MCR Mission Concept Review
ACR Alternative Concept Review
4 ELEMENT
SRR System Requirements Review
SDR System Design Review
PDR Preliminary Design Review
CDR Critical Design Review
FRR Flight Readiness Review
PRR Production Readiness Review 5 COMPONENT
ORR Operational Readiness Review
DR Decommissioning Review
SE process used at each system level and throughout the product life cycle.
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7. NASA Systems Engineering Process
• NASA Guiding Documents
 NPR 7123.1A - NASA Systems Engineering Processes and
Requirements w/Change 1 (11/04/09)
 Systems Engineering NPR Implementation Plan
 SP-2007-6105 NASA Systems Engineering Handbook
 Project System Engineering Management Plan (SEMP)
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8. NASA Governing Documents
From: “NPR 7123.1A Overview”
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9. NASA Systems Engineering
Framework
• Three elements that make up NASA systems engineering capability
 Common Technical Processes
 Tools and Methods
 Workforce
NPR 7123.1A, Figure 1.1

10. NASA Systems Engineering Engine
NPR 7123.1A, Figure 3.1 Page 10

11. Application of SE Engine Processes
within System Structure
NPR 7123.1A, Figure 3.2 Page 11

12. Recommendations for Project
Managers
• Hire Experienced & Knowledgeable Staff
 Multidisciplinary SEs (domain/mission/product experts)
 Apply the “TRL” process to your key personnel
 Get expert advices
 Non-Advocate Reviews, industry advisory groups, etc.
 Not just technical, but also on management practices
• Plan, plan, plan … then plan some more
 Failure to plan = Plan to fail
 Unrealistic schedule = cost over-run
Launch Systems (Level II) Functional
Breakdown Structure (FBS)
SPACE TRANSPORTATION SYSTEMS BREAKDOWN STRUCTURE (SBS) TEMPLATE
SBS Indentured No. (2nd Lvl)
Space Transportation Vehicle
SBS Indentured No. (3rd Lvl)
SBS Indentured No. (4th Lvl)
SBS Indentured No. (1st Lvl)
SBS Indentured No. (5th/6th
Generic Design Disciplines
Space Transportation
Propulsion Subsystems (Level VI)
Architectural Concept
Propulsion Subsystems (Level VI)
Generic Function
Functional Breakdown Structure (FBS) Work Breakdown Structure (WBS)
Element
FBS
Generic Function Description (SBS 5th/6th
Lvl)
VEHICLE 1.0
Level)
System Architectural Concept Name
1.3.1
Propulsion Subsystem
1.1 Vehicle Element (e.g., Booster, Orbiter, Payload element, repeat as needed for elements) Hardware
C D E F G H I
1.1.1 Airframe Structure & Mechanisms
229 1.1.2 Propulsion
1.1.2 Propulsion
230 1.1.2.1 Booster/Planetary Ascent Propulsion
1.1.3 Power Management
231 1.1.2.1.1 Fill & Drain 1.3.1.3 1.3.1.5 1.3.1.7
1.1.4 Thermal Management 1.3.1.1 1.3.1.2
Pressurization
1.3.1.4
Propellant Feed
1.3.1.6
Thermal Control
1.3.1.8
232 1.1.2.1.1.1 Oxidizer F&D system Tankage Thrusters Fill/Drain System Instrumentation Ancillary Hardware
1.1.5 Guidance, Navigation and Control System System System
233 1.1.2.1.1.2 Fuel F&D system t
1.1.6 Communications, Control and Health Management
INTERFACE 1.1.7
1.1.8
Life Support
Environmental and Safety Management
234
235
1.1.2.1.2 On-Board Propellant Storage
1.1.2.1.2.1 Oxidizer tank 1.3.1.1.1
1.3.1.2.1
Orbital 1.3.1.3.1 1.3.1.4.1 1.3.1.5.1 1.3.1.6.1
1.3.1.7.1
Active Thermal
1.3.1.8.1
Power Distribution
236 1.1.2.1.2.2 Fuel tank Pressurant Tank Maneuvering Latch Valves Fill/Drain Valves Latch Valves Pressure Sensors
Control & Harness
1.2 Vehicle Elements Integration (Booster, Orbiter, TLI element, Planet or Moon Decent/Ascent element) Engine
237 1.1.2.1.3 Cryogenic On-Board Propellant and hardware Conditioning for Engine Start
1.2.1 Element to element structural attachment 238 1.1.2.1.3.1 Oxidizer bleed or bubbling system to provide thermal conditioning 1.3.1.2.2 1.3.1.6.2 1.3.1.8.2
1.3.1.1.2 1.3.1.3.2 1.3.1.4.2 1.3.1.5.2
1.2.2 Element to element communication 239 1.1.2.1.3.2 Fuel bleed and fluid circulating system to provide thermal conditioning Reaction Control Temperature Secondary
Propellant Tank Pyro Valves Filters Filters 1.3.1.7.1.1
Engine Sensors Structure
1.2.3 Provide monitoring & control of safe environment between elements 240 1.1.2.1.4 Storable Propellant Conditioning for Engine Start Heaters
GROUND 1..3
1.2.4 Element to Element Separation
Ground Infrastructure Element(s)
241
242
1.1.2.1.4.1 Engine oxidizer feed system fill & bleed
1.1.2.1.4.2 Engine fuel feed system fill & bleed 1.3.1.1.2.1
1.3.1.2.3
Engine Controllers
1.3.1.3.3
Filters
1.3.1.4.3
Fill/Drain Lines
1.3.1.5.3
Propellant Feed
Lines 1.3.1.7.2
Propellant Tank Passive Thermal
1.3.1 Flight Element Processing 243 1.1.2.1.5 On-Board Purge Structure Control
1.3.2 Payload Element Processing 244 1.1.2.1.5.1 Engine oxidizer system purge & conditioning to remove contamination
1.3.1.3.4 1.3.1.5.4
1.1.2.1.5.2 Engine fuel system purge & conditioning to remove contamination 1.3.1.1.2.2
1.3.3 Integrated Processing 245
Propellant
Pressure Feed Subsystem
1.3.4 Flight and Ground Traffic Control and Safety Management 246 1.1.2.1.6 Pressurization Management
Regulators Valve Drivers 1.3.1.7.2.1
247 1.1.2.1.6.1 Oxidizer tank pressurization Device Insulation/Blankets
1.3.5 Ground Infrastructure Support and Management
248 1.1.2.1.6.2 Fuel tank pressurization 1.3.1.3.5
Pressurant Lines
1.3.1.3.6
Pressurization
Subsystem Valve
Drivers
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13. Recommendations
• Trade, trade, trade …. Then trade some more
 No “point design”
 No “show stoppers”
 Technical, cost & schedule
 Challenge technical teams on “what – if’s”
• Manage stakeholder expectations & requirements “creep”
 Establish early, seek inputs
• Execute, execute… and execute
 Make decision !
 Indecisiveness causes schedule delay, cost-over run with no
accomplishments
 Streamline Control Board Process
 Requirements & Change Management
Latency
• Communicate, communicate, and more
 Keep the team informed
 Listen to the team (feedback)
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14. Technical Recommendations
• Minimize Technology Development in a Launch Vehicle Project
 Require component/ subsystem technology at TRL > 6
• Get decisions made between elements (Payload, LV, and Ground
Systems)
 Lack of decision makers delay schedule & increase cost
• Allow technical teams to communicate
 Avoid “silos” mentality
• Do not manage by Spec and ICDs
 Manage by decision – making, not by documentation
• Design-to-Requirements, not Design-to-Performance
 Control technical metrics, affordability, and schedule
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15. Questions?
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