Section 6 Survey of Residual Risk

1
Section 6 Survey of Residual Risk

• Initial Survey of Residual Risk
• Recent Reviews Considering Residual Risk
• Special Topics
• Redbook Candidates
• Launch Liens

. . . Bryant Cramer NMP Implementation Manager
2
Introduction

• Completion of EO-1 has been significantly
  affected by the Red Team process
• Red Team Charter focuses on Residual Risk
• Consequently, the EO-1 Project has made the
  consideration of Residual Risk a specific part of
  each recent presentation
• The involved reviews are as follows
• Initial Pre-Ship Review December 15-17, 1999
• Red Team Review March 28-31, 2000
• Red Team Follow-Up Meeting June 13, 2000
• Delta Pre-Ship Review August 8-9, 2000
• Flight Software Independent Assessment September
  8, 2000
• Operational Readiness Review October 3, 2000
• Mission Readiness Review October 5, 2000

3
Initial Pre-Ship Review

• Held the initial Pre-Ship Review on 12/15-17/99
• WARP failure had not yet occurred
• Launch still planned for 04/13/00
• Wanted to discuss the results of Thermal Vacuum
  Test 1
• Acknowledged that considerable work remained to
  be completed
• At that time, 57 specific tasks were presented as
  remaining work and areas of potential residual
  risk
• All but one has been completed with no untoward
  outcomes
• The remaining task, the Launch Dress Rehearsal,
  normally occurs a few days before launch and is
  scheduled by KSC

4
Initial Survey of Residual Risk

• Preparatory to the Red Team Review on 3/28-31/00,
  we did a Survey of Residual Risk
• Developmental activities were tracked through
  community-based databases
• There are eight such databases
• Project-Level Reviews
• Spacecraft
• Flight Software
• Operations
• GSFC / NCR
• Materials / Processes
• Waivers
• Schedule Liens
• Vast majority (gt90) of all entries are in the
  first four databases, but since
• Flight Software entries generally mirror
  Spacecraft entries, and
• Operations database does not include flight
  hardware -- therefore
• Only the Project-level reviews and the Spacecraft
  databases were surveyed for residual risk in
  preparation of the initial Red Team Review

5
Initial Survey of Residual Risk (continued)

• All of the RFAs were reviewed and 82 were
  selected to have potential residual risk
• All of the PRs after starting with the first
  Thermal/Vacuum test were reviewed and classified
• Any change to flight hardware
• Any change to flight software
• Any Redbook candidate
• Any operational constraint
• Any open item affecting flight hardware /
  software
• Any significant test anomaly occurring during IT
  was also selected as a Special Topic (57)
• These 263 residual risk candidates were reviewed
  and accepted by the GSFC Systems Safety and
  Mission Assurance Office on 3/17/00
• All of these residual risk candidates were
  addressed in the Red Team Review with the mission
  elements wherein they reside
• Red Team concerns were almost entirely restricted
  to the Special Topics

All of these were selected (124)
6
Initial Red Team Recommendations (5/9/00)

• Spacecraft is a single-string design
• Risk Mitigation
• Obtain at least 300 hours of failure-free
  operation on the entire spacecraft Estimate
  289
• Implement the Accelerated Minimal Mission DONE
• WARP is required for the Minimal Mission
• Risk Mitigation
• Obtain at least 300 hours of failure-free
  operation ESTIMATE 700
• Perform WARP Parts Stress Analysis DONE
• Design a WARP Back-Up DONE
• Flight Software still undergoing change with
  minimal failure-free hours
• Risk Mitigation
• Conduct walk-throughs of all critical flight
  and ground S/W DONE
• Freeze FSW DONE
• Exercise this FSW in T/V testing DONE
• High-Fidelity hardware / software test bed does
  not exist
• Risk Mitigation
• Supplement FSW Maintenance Facility DONE

7
Initial Red Team Recommendations (continued)

• QA process applied to GSFC GFE inconsistently
• Risk Mitigation
• Maximize failure-free operating time DONE
• Implement Accelerated Minimal Mission DONE
• Helium adsorption on HRGs
• Risk Mitigation
• Do a worst case analysis DONE
• Improved nitrogen purge DONE
• WARP, PSE, and ACDS had thermal cycling as
  opposed to thermal / vacuum testing
• Risk Mitigation
• Determine thermal stresses at maximum power
  levels DONE
• Evaluate performance in T/V testing DONE

All initial Red Team Recommendations Accomplished
!
8
Red Team Follow-Up Meeting

• The Red Team Follow-Up Meeting on 6/13/00
  involved the following
• Presentation and discussion of PRA, FMEA, and FTA
• Review of earlier Red Team RFAs
• PRA results
• Reliability of Minimal Mission _at_ 1 year is 0.75
• Accelerating the Data Collection Events from four
  / day to eight / day allows the Minimal Mission
  to be largely completed in four months at a
  reliability of 0.90
• Red Team strongly recommended the implementation
  of the Accelerated Minimal Mission to achieve the
  higher reliability
• All RFAs from the initial Red Team Review were
  accepted
• Two new RFAs were added
• Factor the 1R failures into the reliability
  calculations
• Describe the single-point failures associated
  with the Safehold Mode
• These RFAs have since been completed and accepted

9
Delta Pre-Ship Review

• Delta Pre-Ship Review held on 8/8-9/00
• Combination review
• Traditional Pre-Ship Review
• Final Red Team Review
• Single Board -- Co-Chaired by Charles Vanek and
  Ron Thomas
• Three areas of potential risk identified
• S-Band Transponder
• Launch Vehicle Fairing
• Flight Software Independent Assessment
• All three will be presented as Special Topics
• 21 RFAs assigned and have since been submitted

10
Flight Software Independent Assessment

• Held at GSFC on 9/08/00
• Two members of the IVV Facility (West Virginia)
  visited GSFC
• Requested documentation was posted at a web site
  two weeks prior to the visit
• No formal presentations during the visit
• Team spent the morning asking questions
• Later inspected software documentation and
  databases
• Organized by Bill Jackson, IVV Deputy Director
• A different kind of review -- favorable
  impressions on both sides
• Treated as a separate Special Topic
• No show-stoppers
• Made eight risk mitigating recommendations that
  we have adopted
• Final Report included in Probabilistic Risk
  Assessment document

11
Operations Readiness Review

• Operations Readiness Review (ORR) held on 10/3/00
• Combination Review
• Traditional ORR -- chaired by
• Red Team represented by Ann Merwarth
• Walk-on chart summarizing the outcome to be
  presented at the MRR

12
Special Topics

• 1. WARP Status
• 2. S-Band Transponder
• 3. Launch Vehicle Payload Fairing
• 4. Hyperion Calibration Lamps
• 5. Flight Software Independent Assessment
• 6. Sprague Capacitors

13
Special Topic Wideband Advance Recorder /
Processor (WARP)
14
WARP Status (1 of 3)

• Wideband Advanced Recorder / Processor (WARP) is
  a microprocessor-based 48 Gb solid state memory
  that ingests all imaging data from the three
  instruments at about 500 Mb/sec
• It is essential for the Minimal Mission
• A 10V regulator failed initially on 1/4/00 and
  again on 2/13/00 -- the problem was found to be a
  failed Zener voltage regulator
• The failing part overstressed other parts so that
  the entire 10V regulator board was replaced
• The WARP was re-assembled, re-verified, and
  returned to the S/C on 5/15/00
• Re-verification consisted of
• Conducted susceptibility
• Conducted emissions
• 3-axis vibration at workmanship levels
• Four temperature cycles
• Functional tests between each environmental test
• Re-integration onto the Spacecraft was
  accomplished with no difficulty

15
WARP Status (2 of 3)

• After re-integration there was a second
  spacecraft Thermal / Vacuum test (T/V II)
• Three trips to 40C for a total of 136 hours
• Two trips to 5C for a total of 135 hours
• A complete CPT at 40C and 5C
• Four functional tests during T/V II
• Over 100 DCEs transmitted
• No difficulties encountered
• Over 500 hours on the new regulator board with no
  problems
• Now over 2500 hours and well over 400 DCEs on the
  rest of the WARP
• Calculated reliability at one year is 0.90
• WARP is ready to fly !

16
WARP Status (3 of 3)

• After second WARP failure, it was decided to
  pursue a Back-Up Solid State Recorder (BSSR)
• The BSSR is a reliable, independent,
  CCSDS-compatible single card solid state memory
  that fits into the WARP with its own separate
  power source
• Team members include Litton, Orbital, and QSS
• Work started in April 2000 and the CDR was held
  in July
• The WARP performed very well in T/V II and work
  on the BSSR was discontinued on 9/30/00
• A complete electrical design was completed for
  the BSSR
• This design would raise the WARP reliability from
  0.90 at one year to 0.97, but cost a nine month
  launch delay

17
Special Topic S-Band Transponder
18
S-Band Transponder (1 of 6)

• During T/V II the S-Band Transponder developed
  storms on the AGC output
• Once properly calibrated, the AGC output is an
  analog signal proportional to the signal strength
  in the receiver and is used for this purpose
• Diagnostic tests isolated the problem to the
  S-Band transponder and it was removed and
  returned to the manufacturer where the problem
  was readily demonstrated (the root cause was not
  determined)
• In the interest of time, the same transponder was
  removed from the Triana mission and sent to CONIC
  for further evaluation prior to EO-1 integration
• This transponder experienced two brief AGC
  transients while in test of CONIC
• To demonstrate that these were random events,
  this transponder was then exposed to 50 thermal
  cycles (-20C ? 65C) in vacuum over a week

19
EO-1 S-Band Transponder Test Logic(2 of 6)
20
Thermal Cycling of S-Band Transponder (3 of 6)
21
S-Band Transponder (4 of 6)

• The AGC was utterly stable and no other problems
  were encountered
• EMI / EMC testing was successfully accomplished
  at an independent lab near CONIC
• Re-integration onto the S/C was successfully
  accomplished
• Successful tests
• RF Functional Test
• One Complete CPT
• Spacecraft Functional Test
• Compatibility Test Van
• Self-Compatibility scheduled for 10/3/00
• This transponder has over 800 hours on it and has
  passed all of our tests

22
EO-1 Launch Site S-Band Integration (5 of 6)
S-Band Integration
16
20
32
184
188
196
72
Denotes cumulative hours on S-band following
integration
23
EO-1 Launch Site Flow (6 of 6)
208
The S-Band Transponder is ready to fly !
24
Special Topic Launch Vehicle Payload Fairing
25
Launch Vehicle Payload Fairing (1 of 2)

• Some small debris was seen on the video of the
  Globalstar-7 mission at the time of payload
  fairing separation
• KSC ERB concluded on 3/3/00 that the actual
  debris was a lubricant called Fluoroglide
• After examining the data, the EO-1 Project judged
  the contamination risk to be unacceptable
• KSC ERB recommended on 6/19/00 not to fly the
  fairing as-is
• In August, Boeing proposed a shield over part of
  the separation line
• This approach was presented to the Delta Pre-Ship
  Review -- the Board, as well as the Project, was
  uncomfortable with this approach
• Boeing agreed to disassemble the fairing, remove
  the Fluoroglide from the rail assembly, and
  re-assemble it using a traditional alcohol
  lubricant that leaves no residue
• This approach has been successfully implemented
• GSFC recommended tests confirmed the removal of
  the Fluoroglide

26
Launch Vehicle Payload Fairing (2 of 2)

• The EO-1 fairing was also slightly damaged while
  in transit to Vandenburg Air Force Base (VAFB)
• Damage was a delamination of about 5 x 7
• Such delaminations sometimes occur in fabrication
  and established procedures are available for
  their repair
• Such a repair was successfully implemented
• GSFC experts reviewed all of the KSC ERB
  documentation and are confident the repair is
  acceptable
• Both issues with the payload fairing have been
  independently reviewed by GSFC experts and are no
  longer a concern to the Project
• The residual risk associated with the fairing is
  acceptably low
• HQ has requested that the Red Team review the
  resolution of these fairing issues
• This Review is then a Launch Lien

27
Special Topic Hyperion Calibration Lamps
28
Hyperion Cal Lamp Anomaly Background

• Hyperion response to primary cal lamp noticed to
  be degraded just prior to EO-1 T/V II secondary
  lamp response normal
• Additional tests performed during T/V II
• Primary lamp response continued to degrade
• Secondary lamp response remained stable after
  small increase in output
• Investigation revealed that the cal lamps were
  changing output because they were not subjected
  to an adequate burn-in prior to installation
• Tungsten-halogen lamps must be burned-in to
  stabilize the filament (that operates at 3000C)
  before use.
• Welch-Allyn recommends burn-in 1 of life 6.5
  hours minimum
• Estimated cumulative on time for Hyperion lamps
  (as of 7/31/00)
• Primary ? 2.5 hours Secondary ? 1 hour
• Additional Hyperion cal lamp burn-in performed on
  spacecraft after EO-1 shipment to VAFB

29
Hyperion Flight Cal Lamp Burn-in Results
30
GSFC Extended Lamp Burn-In Results
31
Maintenance of On-orbit Calibration

• Hyperion radiometric accuracy requirement is 6
• Case 1 Secondary cal lamps continue operation
  during mission
• Stability of secondary lamp output is /- 0.25
• Radiometric accuracy will remain 2.5 to 3
• Case 2 Secondary lamps last through several
  solar cals
• Perform solar cal as early as possible on-orbit
  to calibrate lamp output
• If secondary fails, increase solar calibration to
  daily event
• Uses up one of the eight scheduled image collects
  per day
• Potential degradation in white paint reflectance
  from frequent solar exposure
• Radiometric accuracy will remain 2.5 to 3 with
  lamps intact, degrades to 4 to 5 without lamps
• Case 3 Secondary lamps fail immediately, before
  solar cal
• Rely on solar calibration, cross-instrument (ALI,
  AC) and cross-platform (Landsat) measurements of
  selected ground sites, solar and lunar
  calibration
• Radiometric Accuracy will remain at 4 to 5,
  still meeting the 6 requirement

32
Special Topic EO-1 Flight Software Independent
Assessment
33
Overview

• At the EO-1 Delta Pre-ship Review, Charles Vanek
  recommended an IVV Independent Assessment (IA)
  of EO-1 Flight Software (FSW) to be completed
  before MRR
• The IVV Facility in West Virginia provided two
  senior analysts for three weeks
• Project documentation was provided to IA team
  prior to a face-to-face meeting
• Final Report delivered on 9/8/00
• EO-1 accepted all of the recommendations

34
Assessment Scope

• Check status of program issues from previous
  reviews
• Random test runs to demonstrate
• Command validation (accept valids / reject
  invalids)
• Exception handling
• FSW Patch uplink verification
• Ops mode transitions
• Review problem closures and verification
  techniques
• TSM/RTS and FDC actions and relationship to FMEA

35
Review Materials Provided

• Review Presentations (CDR, PSR, Red Team, and
  Delta PSR)
• FMEA, FTA, and PRA documentation
• Access to PTR, PR, and Work Order Databases
• FSW design specs and data flow diagrams
• Test procedures, setup, and condition
  descriptions
• Test output, logs, and other reporting
  documentation

36
Findings

• No significant risks unresolved from previous
  reviews
• FSW test practices and coverage of the testing
  adequate
• Trending analysis demonstrates that FSW is mature
  and the development process is stable
• No issues identified against fault contingency
  processes or fault handling
• Eight procedural or documentation clean-up
  recommendations which are being completed by the
  Project

37
Recommendations

• Table upload procedures to include processor
  restart recovery check
• Default memory scrub rate to be increased if
  dictated by SEU predictions
• Central server for baseline program documentation
  to be implemented before launch
• Traceability from FSW requirements to test cases
  to be documented before launch
• Future Work Orders to be annotated to identify
  steps that address each PTR closure
• Project to review and close remaining PTRs
• Inaccurate comments in RTS database to be
  corrected
• FDC table entries to be annotated with reference
  sources

38
Special Topic Sprague Capacitors
39
Vishay Sprague Capacitor Issue

• At GSFC, IRAC mission had a Vishay Sprague CWR09
  part failure. GSFC team went to Sprague to
  investigate the issue.
• GSFC discovered that Spragues test procedures
  and test fixture problems have allowed an
  undetermined number of improperly screened
  capacitors to be delivered to several GSFC
  missions (IRAC, EO-1, MAP)
• CWR09 capacitors from Sprague are suspect, if
  they were processed at the West Palm Beach
  facility. Capacitors from Spragues Concord
  facility are not affected.
• Data from the origins of CWR09 lots is being
  gathered by EO-1 part engineers.
• 12 suspect capacitors are in the WARP box.
• Engineers are currently evaluating the specific
  locations are these capacitors to understand the
  severity of this issue.
• CWR06 capacitors from Sprague also may be
  suspect.
• WARP, PSE and possibly ALI may contain these
  suspect capacitors.
• Part Engineer's are evaluating the CWR09 parts
  first, then will investigate the CWR06 parts.
• CWR06 parts are more numerous than the CWR09s.

40
Vishay Sprague Capacitor Issue

• Successful testing of residual parts from same
  lot as flight is a way to mitigate change out if
  sufficient quantities exist, at least 100 per
  lot. Small samples will not provide sufficient
  data. EO-1 does not have sufficient residual
  parts to test, so this is not an option.
• Date Code is not a factor. All date codes for
  parts tested at West Palm Beach facility are
  suspect.
• This issue emerged on 9/29/00 and is still being
  worked.
• The resolution of this issue becomes a Launch
  Lien.

41
Vishay Sprague Capacitor Issue

• At GSFC, IRAC mission had a Vishay Sprague CWR09
  part failure. GSFC team went to Sprague to
  investigate the issue.
• GSFC suspects that Spragues test procedures and
  test fixture problems may have allowed an
  undetermined number of inadequately screened
  capacitors to be delivered to several GSFC
  missions (IRAC, EO-1, MAP)
• CWR09 capacitors from Sprague are suspect, if
  they were processed at the West Palm Beach
  facility. Capacitors from Spragues Concord
  facility are not affected.
• Data from the origins of CWR09 lots have been
  gathered by EO-1 part engineers.
• Six suspect capacitors are in the WARP.
• Engineers are currently evaluating the specific
  locations of these capacitors to understand the
  severity of this issue.

42
Vishay Sprague Capacitor Issue

• Successful testing of residual parts from same
  lot as flight is a way to mitigate change out if
  sufficient quantities exist, at least 100 per
  lot. Small samples will not provide sufficient
  data. EO-1 does not have sufficient residual
  parts to test, so this is not an option.
• Date codes near to IRAC for parts tested at West
  Palm Beach facility are suspect.
• This issue became known to EO-1 on 9/29/00 and is
  now being worked aggressively.
• The resolution of this issue becomes a Launch
  Lien.

43
Current Status

• Screening
• Since the concern is potential early failures
  that escaped through faulty factory screening
  tests, these parts are somewhat less likely to be
  involved due to
• Successful completion of a 50A surge test, and
• Over 2500 hours of use with no difficulties not
  a part of LVPC re-build
• Application
• The six parts are in the WARP RSN
• They are power filters across a 15V regulated
  supply
• They are rated at 50 VDC -- derated gt3 to 1
• This is not a stressful application and promotes
  self-healing of the capacitor current limited
  voltage source
• Still defining the consequences of a failure
• Resolution
• All of the necessary data will be available next
  week
• Codes 300, 400, and 500 will concur and provide
  an e-mail to the PMC Chairman

44
Redbook Candidates

• The EO-1 Project proposes the following ten
  events as Redbook candidates
• In order of priority
• 1. Helium adsorption on HRGs
• 2. Hyperion calibration lamps
• 3. One-time, unrepeatable, unexplained events
• a. Apparent X-Band RF frequency shift
• b. A/D anomalous maximum value
• c. Chassis current transient
• d. Sustained SADA chassis current event
• The helium absorption is a small but real risk
  due to the significant release of helium from the
  Launch Vehicle in the event of a launch scrub --
  we have done all that we can, but a small, finite
  risk remains
• The rest are of minimally low risk

45
Redbook Candidate (1 of 7)

• Litton Space Inertial Reference Unit uses three
  Hemispherical Resonator Gyros (HRGs)
• Atmospheric helium adsorbs on the quartz of the
  HRGs increasing their Parametric Drive Voltage
  (PDV)
• Not a problem until Spacecraft arrived in
  Building 7 where helium is used in the
  environmental chamber testing processes
• PDV initially about -1.0V and decreased to -2.80V
  within a month. HRGs fail to reliably start when
  below -5.0V
• Nitrogen purge quickly installed and subsequently
  improved including continuous atmospheric
  monitoring
• Primary helium source determined to be a vent
  near the Building 7 air intake -- since moved
• This approach has been successful and implemented
  at the launch site for continuous purging while
  at VAFB and on the launch stand
• PDV is slowly increasing and now stands at -2.6V
• Our goal was to be above -4.0V throughout the
  launch campaign and we have met this goal
• Remaining risk is the potential release of
  significant helium from the launch vehicle in the
  event of a launch scrub and our purge system
  fails outright
• We are theoretically protected, but a small,
  finite risk remains in the event of a launch scrub

46
Redbook Candidate (2 of 7)

• Directly prior to T/V II, the Hyperion primary
  calibration lamps were found to be degraded, but
  the secondary was normal
• Investigation revealed that the calibration lamps
  were not adequately burned-in
• During additional burn-in, a primary calibration
  lamp failed
• Subsequent examination of 15 bulbs from the same
  lot revealed
• An anticipated life of 146 hours -- quite
  adequate for the mission
• Halogen cycle not working well at ambient
  pressure
• Halogen cycle working properly in vacuum
• To change out the primary calibration lamps is a
  two-month launch delay
• The secondary is stable and should last
  throughout the mission
• These calibration lamps are transfer standards
  between solar calibrations
• Operational workarounds have developed to
  compensate for the loss of the secondary
  calibration lamps and still maintain radiometric
  accuracy
• This is a negligible risk -- See Special Topic
  for details

47
Redbook Candidate (3 of 7)

• After Spacecraft vibration on 8/4/99, the first
  attempt to use the X-Band downlink resulted in
  failure to achieve carrier lock
• Test personnel saw an apparent frequency shift of
  6-7 MHz on spectrum analyzer
• The next day, more equipment was brought in to
  examine the problem, but it disappeared and never
  occurred again
• Detailed examination failed to find the cause of
  the problem so a panel of independent experts was
  convened by the Deputy Center Director
• FTA performed and individual branches
  systematically ruled out
• Experts Findings
• Flight hardware essentially ruled out as probable
  cause
• Most likely cause was RF GSE cables that were
  damaged in handling / use
• Damaged cables display selective frequency
  attenuation (SFA) that leads to loss of carrier
  lock and an apparent frequency shift
• These cables were replaced by the Project early
  in its investigation

48
Redbook Candidate (4 of 7)

• Some of these RF GSE cables were subsequently
  found and tested -- they displayed SFA
• David Israel (Code 527) was able to successfully
  model an apparent frequency shift based on SFA
  for comparable cables
• X-Band System now has over 700 hours on it since
  this one-time incident and has successfully
  downlinked well over 300 DCEs
• Although never specifically reproduced, there is
  strong circumstantial evidence to believe that RF
  GSE cables were responsible for this one-time
  event
• This concern is of negligible risk to the mission

49
Redbook Candidate (5 of 7)

• PR-837-20-1 While loading software in the
  housekeeping RSN, the A/D in the PSE RSN
  indicated that the PSE LVPC total output current
  was FF or 19.275A for one sample while the
  Spacecraft was quiescent and no heaters were ON
• Occurred only once in over 2500 hours (gt9 x 106
  samples)
• LVPC overcurrent trip did not occur
• Umbilical telemetry (battery current, battery
  voltage, and chassis current) remained nominal
• Fault tree analysis completed and each branch
  explored
• No credible cause was identified
• No evidence of FF representing actual current
• GSE found to be operating normally
• A/D timing explored and found to be adequate, but
  marginal
• Conclude this is a random event of unknown
  etiology
• Judged to be a random event of low risk to the
  mission

50
Redbook Candidate (6 of 7)

• PR-770-20-3 describes a one-time transient of
  300ma chassis current that occurred on the
  stripchart recorder on 11/22/99
• The transient was less than one second in
  duration
• The event was also seen in the telemetry
• EMC testing was occurring at the time of the
  transient and various test probes were connected
  to the Spacecraft power bus
• Investigation was unable to identify a probable
  cause
• This transient was most likely associated with
  the GSE used in the EMC testing
• As such, this one-time transient is of negligible
  risk to the mission

51
Redbook Candidate (7 of 7)

• PR-572-30-10 describes a prolonged chassis
  current of 925 ma on 8/20/99
• Ad hoc testing following the event was able to
  reduce the problem by moving the Solar Array
  Simulator Cable (EGSE)
• Inspection of this cable revealed split
  insulation on several wires in the backshell of
  the connector
• A new Solar Array Simulator Cable was fabricated
• In the succeeding 2500 hours of Spacecraft
  powered testing the problem has not recurred
• Although we cannot be absolutely certain, there
  is strong presumptive evidence that the failed
  insulation in the EGSE cable was responsible for
  this event
• This event is of negligible risk to the mission

52
Launch Liens

• Successful completion of remaining planned work
• Sprague capacitors in WARP LVPC (IRAC problem)
• Conduct Red Team review of fairing issues
• Complete closure of open paper
• Completion of any RFAs from MRR
• Presentation of MRR Overview to Office of Earth
  Science