Flight Assurance

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Section 31 Flight Assurance
. . . Michael P. Kelly EO-1 Systems Assurance
Manager
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Contents

• Parts Status
• Software Assessment
• Reliability Assessment
• Safety Status
• Spacecraft Independent Inspection
• Critical Problem Records/Issues
• Transponder Rework and Retest Plan
• Remaining Work
• Summary

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Parts

• All Hyperion and ALI radiation issues have been
  worked by GSFC radiation and parts personnel.
  There is minimal risk to the mission.
• All part waivers have been approved by the SAM
  and the Mission Manager.
• GIDEP Alerts are constantly being evaluated
  against the EO-1 part list.
• No recent matches identified

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Software Assessment

• Per Code 300 Directors request, a software
  assessment was conducted of both the flight and
  ground code for this mission.
• Code 300 representatives were very satisfied with
  the software code. This is good news for the
  project.
• An agreement was reached between the Project and
  Code 300 to perform Independent Verification and
  Validation in West Virginia for this mission.

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Reliability Assessment

• Spacecraft Probabilistic Risk Assessment (PRA)
  has been completed
• All risk assessments were presented at the last
  Red Team Review
• Complementary use of Failure Mode Effects
  Analysis (FMEA), Fault Tree Analysis (FTA), and
  PRA
• Reliability of the EO-1 minimal mission is 0.7447
  _at_1 year
• By going to the Accelerated mission, the
  probability of completing the Minimal Mission
  increases to 0.90

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Safety Status

• Final Revision to Hazardous and Non-Hazardous
  TOPs are in process by Swales
• Final Update of the MSPSP is in process by Swales
• Currently, no safety issues at GSFC or Launch Site

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Spacecraft Independent Inspection

• Supplier Assurance Contract Representative
  (Warren Nichols - ex-Langley) performed an
  independent hardware inspection of the spacecraft
  prior to second Thermal Vacuum test
• Only two issues were identified during the
  inspection.
• Thinning paint on ALI instrument (Accepted by MIT
  and has no impact on performance)
• Staking of screws on the AC instrument (Not
  required)
• Both issues were evaluated and dispositioned as
  use-as-is

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Critical Problems Records/Issues

• The following is a list of current issues on SAM
  watch list
• Helium Issue for IRU
• SAM Opinion Need to track this at the launch
  site. IRU appear to be holding steady. (just a
  bit of margin though) I am concerned about this
  one.
• Image Star Tracker Issue (potential impact on
  EO-1 Mission)
• SAM Opinion Image Star Tracker appeared to be
  improving. Probably a non-issue for EO-1.
• X-Band Frequency Shift
• SAM Opinion 99 a GSE cabling issue. This will
  be discussed in the Mission Redbook.
• T/V Chamber at -20 degrees C
• SAM Opinion X-Band Antenna appears to be okay.

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Critical Problems Records/Issues

• Hyperion Primary Calibration Lamps
• SAM Opinion Unknown cause of degradation with
  primary lamps. Secondary appear to be fine. I
  am concerned about this issue. This will be
  included in the Mission Redbook.
• Transponder AGC Drop outs
• SAM Opinion See next chart for more details

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Transponder Rework Plan

• AGC Anomaly has been 100 verified in the
  transponder testing at Loral Conic.
• SAM is satisfied with spacecraft shipping to
  launch site without transponder
• Visual Inspection of the transponder has
  uncovered two problems
• 3 broken coaxial cables, and 1 other damaged due
  to inadequate stress relief
• Disposition Repair all 4 cables and inspect the
  rest of the coaxial cables throughout the
  transponder
• Hole in diode on the VCXO Module
• Disposition Perform failure analysis of this
  diode and replace with new diode
• Replace only Category IV ATC Capacitors (2 in
  total)
• All other ATC Capacitors were cleared by testing
  of spares from the same lot

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Transponder Retesting Plan

• SAM Proposed Retesting Plan
• Pre-Acceptance Test Thermal Cycling
• Full Acceptance Testing
• 8 thermal vacuum cycles in total (conduct 4
  cycles of thermal vacuum, then vibration, then
  last 4 thermal vacuum cycles)
• powered vibration, 3 axes at launch loads
• EMI testing (to be evaluated)

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Remaining Work

• Minor Waivers must be documented and formally
  submitted to the project from the LVPC Circuit
  Analysis performed by STI
• NCRs for the WARP - SAM has the action
• Updated Spacecraft Verification Specification
  (SAI-SPEC-158) - Swales is working
• Safety Waivers Need Mission Manager Signature

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Summary

• All waivers have been approved by the SAM and the
  Mission Manager
• All spacecraft testing has been completed and is
  properly documented
• SAM agrees the spacecraft is ready for shipment
  to the launch site