GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 1 GLAST Large Area Telescope: LAT System Engineering Pat Hascall SLAC System Engineering Gamma-ray Large Area Space Telescope

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 2 Topics Action Item Status Technical Baseline Management Requirements Management and Verification Planning Interface Control Documentation RFA Closure Key Metrics Risk Management

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 3 Monthly Action Item Status

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 4 Drawing Release Status Drawing preparations at SLAC matched needs for November (still need a few status updates to be sure) Drawing release did not keep pace –Tracker team put in 30 drawings in November that are still not released Due in part to vib test results – have broken free drawings unaffected by that test Have instituted a better tracking system to provide better visibility into where drawings are in the release cycle –Mechanical, Cal and Electrical on track –ACD report is incomplete but progress is apparently 46 drawings behind release plan Additional drawings identified –Four Tracker drawings –14 Outline drawings needed by Integration Intermediate link between subsystem models and LAT model –Three harness drawings

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 5 Planned Drawing Release

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 6 Issues

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 7 Issues (Continued)

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 8 Issues (Continued)

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 9 Issues (Continued)

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 10 Requirements & Performance Verification Progress Test Data Requirements –New direction to add appendix to LAT-MD for each subsystem defining End item data packages (12/10 F to F) Test Planning –Post CDR LAT-MD out for signatures Highlights include: –Changes TKR & CAL to Proto Flight Programs –Updated EMI section –New Assy & Test Flow –Added strength Testing

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 11 Updated LAT Performance Verification Plan Additions –Added section on plan for the test plans –Updated and re-formatted reference documents –Added section on Strength Testing Deletions –Removed reference to an ESD compatibility test –Removed Appendix-A, example Test procedures Changes –Updated LAT Assembly and Test Flow –Updated EMI/EMC Section to reflect latest post CDR requirements –Updated document release matrix –Updated section on Test Data Packages –Changed Tracker to a Proto Flight Program –Changed Calorimeter to a Proto Flight Program –Provided details on alignment and Survey –Updated LAT Thermal Vacuum cycle plot (from CDR)

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 12 Test Plan Schedules LAT I&T - Assembly Plan – 12/19/03 LAT Comprehensive Performance Plan- 6/04 LAT Limited Performance Plan - 6/04 LAT Operational Performance Tests - 3/04 LAT Instrumentation Plan - Update 1/16/04 LAT Survey Plan – 1/16/04 LAT Dynamics Test Plan – First Release 12/19/03, Final 3/04 LAT Thermal Test Plan - First Release 1/16/04, Final 3/04 LAT EMI/EMC Test Plan - First Release 3/04

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 13 Interface Management

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 14 LAT-SC Interface – Open Issues

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 15 ICN’s LAT signed this month –ICN-9 Reduce the High Speed Serial Science Data Rate ( ) –ICN-17 LAT Orientation during TVAC Testing ( ) –ICN-25 Add SC RT to 1553 Protocol Document ( ) –ICN-37 Add Digital Grounds to Connector Pin-outs ( ) –ICN-36 LAT-SC Mechanical Interface ( ) Currently under signature review –ICN-39 PRU Over-Voltage Limit Currently in draft or revision –ICN-33 LAT Analog RTD Part Type

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 16 Interface Documentation Status

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 17 Working CDRL Delivery List

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 18 RFA Closure Coordinated plan of attack in place –Horn/Graf/Hascall/Melton –37 CDR RFAs total, submitted 21 answers, have 5 draft answers Preparations for MRRs are driving RFA closure priorities Current status of all RFA’s on SE website

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 19 Key Design Metrics

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 20 LAT Mass Status

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 21 November 03 LAT Power Status (Proposed) Operational Power

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 22 November 03 LAT Power Status (Continued) Survival Power Changes to power budget –Updated Trigger and Data Flow Included design presented during Power Supply Peer Review (removed linear regulators) Incorporated measurements in power supply efficiencies –Survival power updated to reflect selected heaters

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 23 FSW Resource Usage Current Estimates ResourceTotal AvailableAnticipated Usage Margin Factor EPU Boot PROM256 kB128 kB2 SIU Boot PROM256 kB128 kB2 EPU EEPROM6 MB1.5 MB4 SIU EEPROM6 MB MB3 EPU CPU cycles200% in 2 EPUs30%> 6 SIU CPU cycles100% in 1 SIU25%4 EPU memory128 MB16-32 MB4-8 SIU memory128 MB< 16 MB8 Bandwidth – instrument to EPU45 MB/sec10 MB/sec4.5 Bandwidth – EBM to CPU20 MB/sec5 MB/sec4 Bandwidth – CPU to EBM2.5 MB/sec20 kB/sec125 Bandwidth – EBM to SSR5 MB/sec40 kB/sec125

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 24 Key Science Performance Metrics

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 25 Risk Management

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 26 Risk Management Activity No new issues

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 27 Top risks to cost ID #Risk Rank Risk DescriptionRisk MitigationStatus Proj Mgt Moderate Parts and vendor orders have not been completed therefore flight production cost may exceed projection Manufacturing engineer added to expedite minimum cost closure Clarification and purchase package review to ensure accurate bids Processes in place Remaining vendor selections by 11/03 Proj Mgt Moderate Critical skilled positions (senior personnel) required to execute project remain open, potential impact to cost and schedule if not closed in short term Management team has identified critical skill needs Identify skilled personnel within Collaboration environment Added SLAC Site Rep in Italy Added Scientist to Tracker Team & Proj Eng Continuing to expand FSW support Identified additional QA support requirements Added additional Structural analyst support Added Design Eng Support

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 28 Top risks to schedule ID #Risk Rank Risk DescriptionRisk MitigationStatus Proj Mgt Moderate Completion of Tracker subsystem qualification program delayed due to EM closure or MCM electronics Manufacturing Eng assigned to close MCM issues Increased team integration with Italian partners GSFC audit/support to Tracker EM closure 50 Unit Pre-production run established with Teledyne, ECD: Jan 04 Engineer (Dave Rich) added to drive closure Added Design Eng Proj Mgt Moderate ASIC’s fail to meet requirements; results in schedule impact Focused review & test. Margin for re- runs protected where possible Individual risks Identified by subsystem DAQ ASIC’s flight ready, continued testing Tracker GTRC error found, plan in place Cal/ACD ASIC’s continued testing Proj Mgt Moderate TEM Power supply final design is delayed, final implementation may exceed current schedule Key focus item identified for DAQ Design peer review 9/03 Basing approach on flight proven designs where possible Peer review completed 9/22/03 Re-baselined, tight schedule for EGSE SE-007Moderate Critical component failure post LAT integration requiring de-integration impacting cost & schedule Extensive use of EM test bed to support flight H/W & S/W development Thorough qualification and acceptance tests Pre planned I&T actions for de- integration LAT Assembly plan under update to incorporate EM1 lessons learned,ECD: Jan 04

GLAST LAT ProjectGSFC Monthly, 15 Dec 2003 LAT System Engineering 29 3-Month Milestones Update the LAT-MD LATPVP – Released for review 12 Dec Complete FMEA – GSFC picking up task, bottleneck is transfer of work in process Complete Spacecraft ICD Rev 2 release review – 19 Dec Close remaining Internal ICD TBX’s - Complete Update System Metrics – Electrical updated this month, next mass update in Feb Complete X-LAT Review –Completed Complete CIDL update – Draft by 19 Dec Close all open RFAs – October->December->??? LAT I&T Assembly Sequence – 19 December Draft Dynamics Plan – 19 December LAT Survey Plan – 16 Jan 04 LAT Instrumentation Plan – 16 Jan 04