Summary of Open Work Orders and Recent Problem Reports

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Section 8 Summary of Open Work Orders and Recent
Problem Reports
. . . Mark Perry EO-1 Spacecraft Systems
Engineer, Swales Aerospace, Inc.
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Work Order Status

• Total number generated from start through 8/4/00
  1133
• Number Closed out 1119 (98.7 closure rate)
• Number open 14 (as of 8/4/00)
• Work In Process 1
• Problem Reports 2 (S-Band Transponder 1)
  ( Hyperion CAL Lmap 1)
• Redbook Item WOAs 5 (each discussed in depth)
• WOAs in closure process 6

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60 PRs During the T/V Test

• 8 PRs relating to hardware problems
• 7 PRs for the S-band Transponder (AGC anomaly)
• 1 PR for degradation of the Hyperion primary
  calibration lamp
• 29 nominal conditions initially perceived as an
  error
• Includes noisy A/D converter data, limit
  violations, high temperatures, TSM tripping,
  error counters, telemetry delays, event messages,
  low voltages
• 12 errors, including 8 procedure errors and 4
  operator errors
• 3 GSE problems ASIST, FEDS, and UPS
• 1 database PSE half-voltage FDC calibration
• 7 still under investigation (PR number in
  parentheses)
• Cold X-band (1099-20-2)
• LEISA telemetry drop-out (1099-20-12)
• 3 WARP S/W bus error counters (1099-20-15,
  1101-20-9, 1102-20-5)
• S-band RF temperature telemetry momentarily went
  to maximum value (1101-20-4)
• Momentarily low voltage on Hyperion 5-volt supply
  (1102-20-8)
• None of the PRs under investigation are
  considered significant

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Open Problem Report Status

• Total number generated from start through 8/4/00
  1696
• Total number generated since Red Team Review
  124
• Number Closed out 1664 (98.0 closure rate)
• Number open 32 (as of 8/4/00)
• Work In Closure Process 16 (Procedure error and
  database update)
  1 (EGSE)
  
• Test verification required 9 (S-Band
  Transponder)
• To be resolved 1 (TRW CAL Lamp Problem)
• Redbook Items 5
• WOA 468-20-4 IRU Helium Exposure (see ACS
  Subsystem)
• WOA 512-150-1 X-Band Frequency Shift (see RF
  subsystem)
• WOA 572-30-10 Bus Chassis Current Exceeding
  .925mA (see Electrical Subsystem)
• WOA 770-20-3 One Time Event Chassis Current
  during EMC Testing (see Electrical Systems)
• WOA 837-20-1 One Time Event LVPC Current Red
  Limit (see Power Subsystem)

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Quality Assurance Spacecraft Bus ElementsSummary
of Open PRs as of 8/4/00

• Hardware
• S-Band AGC anomaly (9 separate PRs generated)
• Degradation of the primary calibration lamp on
  Hyperion (1 PR generated)
• Procedure Error / IT Database Problem
• 16 PRs will be closed once the paper work is
  completed.
• 1 PR EGSE (In process of closure)
• Redbook Items
• 5 PRs as discussed earlier
• Negligible residual risk due to the open PRs

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Quality Assurance Spacecraft Bus Elements
Pre TV 2
Open Problem Reports
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Quality Assurance Spacecraft Bus ElementsOpen
Problem Reports (continued)
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Quality Assurance Spacecraft Bus ElementsOpen
Problem Reports (continued)
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Closure Plan

• All WOAs and PRs to be closed before shipment to
  the launch site.
• Exception will be the WOAs and PRs related to the
  S-Band AGC anomaly and Redbook items.
• Continue use of the WOA and PR system at the
  launch site.
• Any new PRs to be closed before launch, or added
  to the Redbook with concurrence of GSFC and
  Swales quality teams.