Minutes for November 7, 2000 EVA AIT
The EVA AIT met at the Johnson Space Center on November 7, 2000. Boeing/Lou Ramon and XA/Nancy Patrick co-chaired the meeting. Representatives from CB/Flight Crew Operations, XA/EVA Project Office, NC/Flight Systems Safety and Mission Assurance, DX32/EVA Systems/Mission Operations, DO/MOD operations division and Boeing-Houston (EVA, Operations, PEI and Safety) were present. Representatives from the Kennedy Space Center, Marshall Space Flight Center and Boeing Development Centers supported by telecon. Copies of presentations can be obtained from XA/Charlotte Shannon, Building 1, room 661, (281) 483-5259.
1. Introduction/AI Review Boeing/Lou Ramon
XA/Nancy Patrick
The Following Decision Package was distributed for review November 28, 2000:
PG1-P3-400: EVA Bolt Torque Value
The Following Decision Packages were dispositioned (distributed October 10, 2000):
PG1-S1/P1-EV&CS-15-15: Working Volume UDS Line Maintenance Torque Box
Decision: The EVA AIT approved this PIDS exception
Note: This PIDS exception was revised and released as PG1-S1/P1-EV&CS-15-15Rev1 after the EVA AIT and approved out of board. The NBL/WETF test references were updated to indicate later test results that superceded previously unacceptable findings. Additionally, a paragraph and figures were added to the rationale section (section 8) to indicate the touch temperatures both inside and outside the truss in the immediate vicinity of the task. The temperatures cited are within the EMU extended contact allowable temperature range. The paragraph added is as follows:
"Additionally, Boeing-HB Passive Thermal group has provided temperature ranges of structure that is in close proximity of the TRRJ, FHRC and DLA worksites. The temperature range is —100F to +180F. The crewmember will see structure in the range of —65F to 160F internal to the S1/P1 bays and —100F to +180F external to the bays. These ranges are within the EMU temperature limits of —145F to +225F (sic) and should not be a concern. Attachment A shows the location of the temperature ranges within the worksite."
PG1-S1/P1-EV&CS-15-01 Rev2: TRRJ/FHRC and Drive Lock Assy R/R & Assy Tasks
Ms. Patrick requested that for EV&CS 15-15, Huntington Beach try to provide temperature information for the worksite and surrounding area. Ms. Patrick requested this information because of the as yet unresolved thermal issue for extended contact for the EMU.
Deferred from October 24 pending additional information on the thermal analysis information provided (both exceptions), and reconciliation of U2s received in WETF test cited as rationale for exceptions (15-15).
Note: This PIDS exception was revised and released as PG1-S1/P1-EV&CS-15-01Rev3 after the EVA AIT and approved out of board. A paragraph and figures were added to the rationale section (section 8) to indicate the touch temperatures both inside and outside the truss in the immediate vicinity of the task. The temperatures cited are within the EMU extended contact allowable temperature range. The paragraph added is as follows:
"Additionally, Boeing-HB Passive Thermal group has provided temperature ranges of structure that is in close proximity of the TRRJ, FHRC and DLA worksites. The temperature range is —100F to +180F. The crewmember will see structure in the range of —65F to 160F internal to the S1/P1 bays and —100F to +180F external to the bays. These ranges are within the EMU temperature limits of —145F to +225F (sic) and should not be a concern. Attachment A shows the location of the temperature ranges within the worksite."
The Following Decision Packages were dispositioned (distributed October 24, 2000):
NASDA 7/16-inch EVA Bolt Waiver request
Decision: The EVA AIT approved this waiver request
PG1-S1-579R2: S1/P1 Utility Rail Zero-G Connector Spacing Exception
Decision: The EVA AIT approved this PIDS exception
Note: This PIDS exception was revised and released as PG1-S1-579R3 after the EVA AIT. The revision was a minor change to include text concerning additional intrusions of no less than .9 inch for no more than 18°
around connectors P153 and P165. The intrusions were included in the schematics and photos provided and were inadvertently left out of the text. The intrusions are for bolts that are on the opposite side of travel for the bale and therefore should not be a concern.
PIDS Exception PG2-P6-2000-3: EVA Gloved Hand Clearance Requirements for EAS to P6 QD interfaces, was approved out of board on November 14. This PIDS exception was submitted after the EVA AIT and required short turn around to meet STS-97 launch flow schedule requirements. The exception related to the connector spacing for the ammonia servicer QDs. The QD configuration was thoroughly reviewed by the EVA AIT on September 26 when the design change to change from manual valves to QDs was proposed. Ms. Patrick forwarded the PIDS exception by Email and received approval from all relevant parties.
PCU Hazard Reports: Ms. Patrick reviewed and approved out of board the hazard reports associated with PCU failure. There is a hazard to the EVA crew due to arcing from plasma if the PCUs fail to perform and the electrical charge cannot be managed below a voltage level below the nominal charge. The hazard report has been thoroughly reviewed by the STS-97 EVA team through the SRP and Ms. Patrick coordinated the hazard report with those parties.
The Following Action Items were reviewed:
AI-504: This action remains open and will be addressed again on January 16. Mr. Boller reported that WIF 28 is not OTD compatible, which finalizes the compatible WIF list. The only remaining aspect of the action is how Boeing will document the list for formal operations use. Mr. Ramon reported that Boeing is preparing a change to the OP-01 delivery for P6 as the first documentation step while also pursuing the SSODB option.
AI-507: This action remains open and the Actionee changed to XA/Jeff Dutton. It will be addressed again on December 12. MOD has provided the information necessary to determine the final 3A configuration and Ms. Patrick and Mr. Dutton will arrange an evaluation using the NBL mockup.
AI-510: This action remains open and will be addressed again on December 12. Mr. Ramon will try to assist in the investigation.
AI-511: This action remains open and will be addressed again on December 12. Ms. Patrick reported that she now has the points of contact required and will coordinate with them in the next several weeks.
AI-513: This action remains open and will be addressed again on December 12. There is no change in status.
AI-522: This action remains open and will be addressed again on December 12. There was no report on the status.
AI-531: This action was CLOSED. The test has been slipped until probably March, however PG1/George Osorio reported that UMA removal with CAS stowed will be one of the test objectives. The issue will not be completely resolved until all the UMAs can be evaluated, which won’t be possible until the training mockups are delivered due to the fidelity of the development unit.
AI-546: This action remains open and will be addressed again on November 28. There was no report.
AI-547: This action remains open and will be addressed again on November 28. Ms. Patrick reported for Mr. Johnson that the test plan would be reviewed at the EMU board on November 8. Mr. Johnson will report the test plans and status to the EVA AIT on November 28.
AI-551: This action remains open and will be addressed again on November 28. Huntington Beach is still working on the evaluation of this and other interface concerns, such as interferences with the APFR.
AI-552: This action remains open and will be addressed again on December 12. Mr. Ramon reported that the standard procedure for Boeing operations is to review installation drawings (which is where the constraints for Dzus fasteners is documented) and incorporate those types of notes in OP-01. This was not done for the Dzus fasteners for unknown reasons. Mr. Ramon reported that Houston EV&CS will develop a list of hardware related to EVA and IVA operations with the applicable installation drawings and procedures noted. This information will be provided to MOD. Additionally, MOD reported that the note did not appear on the installation drawing for some 7A hardware that uses a Dzus fastener. The EVA AIT suggested that an alert be issued for Dzus fasteners since the problem seems to be fairly common and the recommended resolution/caution is not always captured. Mr. Ramon will look into this option and report the status of this and the generic effort on December 12.
AI-553: This action remains was CLOSED. Mr. Truong-Cao and LMES/Mark Messinger reported the handrail documentation status during the ICD review. See minutes below for additional information and follow-up actions assigned.
AI-554: This action was CLOSED. Mr. Pruett presented the SSCN 3370 status at the EVA AIT. See minutes below for additional information.
AI-557: This action was CLOSED. MOD and the crew office reported the information was provided and sufficient.
AI-558: This action was CLOSED. Both MOD and the crew office determined that the task is feasible. The question remains whether it fits into the timelines without significant and unacceptable impact. Progress was made in allowing additional flexibility for S1/P1 to work on some of the truss mating tasks prior to driving the EVA bolts (i.e. with only the capture latch engaged), which, it is believed, will allow the launch to activation thermal requirements to be met. The analysis still has to be performed for S3/P3 mating tasks. The timeline impacts of incorporating the new tasks, and what gets "bumped" to the increment EVAs is still in work, and will be addressed by the JOP. MOD has identified a problem with performing the contingency task (driving the bolts to a higher torque required due to a failure of the automated bolts) because the torques are too high for the SSRMS to provide a stable platform, and most of the EVA bolts do not have WIF worksites provided.
AI-559: This action was CLOSED. Mr. Smudde and Mr. Gafka met with the JOP the previous week. The remaining actions to resolve the issue are being tracked by the JOP.
2. SSCN 3370 — RS Laptop Cables EV/Dave Pruett
Mr. Pruett described the current status of the development effort and open work remaining. Mr. Pruett explained that the team had focused in on one of the options (option 4.2) as the leading candidate for implementation. This option runs two lines from the FGB/SM connectors, one to the airlock and one to the Hab module. They are trying to build the airlock cable in time to support 7A launch, however no work has been done to manifest the cable. With the middeck stowage concerns on that flight, it may be difficult to get it on the flight, however they are trying to build it so that it can support any launch schedule after it is physically possible to install it.
Mr. Pruett addressed several questions that arose from the EVA AIT discussion on October 10, as follows:
- Question: Are there options for connecting to Node 3 and running the line internal through Node 3 to the hab for the hab module option? (MOD thought that the Node 3 development is still early enough that it might be possible to run some of this line internally, thus minimizing the EVA installation required)
- Question: Additional information is required on the type of cable involved — size, stiffness, fragility, etc.
Answer: Mr. Pruett reported that the team had considered this option, however were under the impression that the Node 3 design is too far along to incorporate the required internal architecture to support this. Several EVA AIT members felt that this wasn’t the case, and Mr. Pruett agreed to look into the option.
Answer: Mr. Pruett did not have the specifics about the cable, but indicated it is a standard data line (i.e. copper, not fiber).
- Question: Option 2 from Mr. Harless pitch (A/L and Hab cable) seems to constrain operations to installing the cable after airlock installation but before High Pressure Gas Tank installation. This would appear to be an unacceptable hit to the 7A flight operations. Further clarification of this option is also required.
- Question: Most of the routing options involve tying off to handrails. Since this seems to be a growing trend for additional cables, the EVA AIT would like to use this cable development effort as a pathfinder to develop a system to use the handrails for securing cables without hampering the use of the handrail for translation.
Answer: Option 2 (referred to now as Option 4.2) evaluation did use the routing path proposed by Mr. Harless, which requires installation of the cable prior to high-pressure gas tank installation. This is unacceptable operationally (especially since its not clear the cable will be launched on 7A) and therefore all agreed a new cable routing is required, one that does not result in derived operational constraints for cable installation. Additionally, the path proposed is in a high traffic pattern for the airlock. B-Hou/Lou Ramon agreed to have B-Hou/Dennis Harless provide two additional routing path options, with the above consideration included. The routing paths will use a handrail tie-off option and an alternative attachment along MMOD shields option (see below).
Answer: Mr. Pruett agreed to add this effort as part of the SSCN. EVA AIT members suggested a couple of options, including stand-offs that attach to the handrail stanchion to off-set the cable away from the handrail, and an attachment device that utilizes the MMOD shield attachment interfaces.
Mr. Pruett noted that the change provides full RS insight and control from the USOS. The EVA AIT concurred that this is a good change for EVA, since the IVA crewmember is responsible for RS health and status in addition to SSRMS support and EVA support during 3 crewmember ISS operations. This capability will allow him to continue working in the USOS when an RS failure occurs.
MOD also suggested that the Early Comm cable rather than install an entirely new cable. The early Comm cable is disconnected at 6A. Although the Early Comm Cable does not provide the full path, it can save significant EVA routing across Node 1. Mr. Pruett agreed to include these ideas into efforts to finalize the cable design.
The EVA AIT concluded that additional work is required to help define the final proposal for installing the cables associated with this change. The EVA AIT and Mr. Pruett agreed to the document the following forward work in the SSCN:
- Define a cable routing path such that there are no operational constraints imposed for when the cables are installed and that maintains a clear airlock translation path.
- Investigate alternative cable attachment options that don’t affect the use of the EVA handrails.
- Make a determination of whether a cable caddie is required
- Conduct NBL testing of the routing path and attachment methods proposed.
- Address manifesting and on-orbit stowage for the cables provided
The EVA AIT agreed that a development team should be formed to address the open work and provide EVA guidance on proposed design options. The following actions were assigned to address the open work. The topic will be discussed again on November 28.
Actionee: EV/Dave Pruett
Due Date: November 28, 2000
Method for Closure: Report to EVA AIT
Actionee: CB/Dave Wolf, DX32/Bob Adams
Due Date: November 28, 2000
Method for Closure: Report to EVA AIT
Actionee: B-Hou/Dennis Harless
Due Date: November 28, 2000
Method for Closure: Present to EVA AIT
Action 564: Coordinate XA, EVA hardware development support for SSCN 3370 alternative cable attachment method development effort.
Actionee: XA/Nancy Patrick
Due Date: November 28, 2000
Method for Closure: Report to EVA AIT
Action Item Closure: AI-554 was CLOSED
3. Node 2/Lab PDGF location OM/Henry Orosco
There was no presentation material for this topic
Mr. Orosco presented the options for locating the PDGF on Node 2. The Node 2 PDGF is required for HTV berthing. The Node 2 PDGF location has been under discussion for almost 2 years. There are three existing options for the PDGF location, however the only option that doesn’t have other issues is one that’s in the vicinity of the Node 2 heat exchanger. There is some concern that the PDGF may be in the way of the heat exchanger task, however if this is the case the PDGF can be temporarily relocated to allow access to the heat exchanger. This will be investigated in an NBL test in December. The EVA AIT concluded that the Node 2 PDGF location recommended is acceptable.
During the discussion, Mr. Orosco noted that the original intent of the CR was to determine whether a PDGF was required for the propulsion module. Mr. Orosco explained that without the prop module PDGF, the Node 2 PDGF has to be moved to the prop module whenever direct unberthing is required. Since direct unberthing is required for almost every ISS visit after assembly complete, and HTV arrives twice per year, the PDGF would have to be relocated approximately 4 times per year. Mr. Orosco explained that the recommendation going forward is to not purchase a prop module PDGF. This decision was made when the prop module was not definite. Since the prop module is now part of the program baseline, the EVA AIT felt that the recommendation should be changed. Four EVAs per year will be difficult to accept, given the current maintenance predictions at assembly complete.
Mr. Orosco explained that the proposal was going forward to the SPCB on November 14 for final disposition. Ms. Patrick agreed to have EVA representation at the SPCB.
Decision: The EVA AIT concluded that the Node 2 PDGF position proposed is acceptable, however a PDGF should be dedicated to the prop module to avoid 4 PDGF relocations per year at assembly complete.
4. 1" Male QD Vent Tool Operational Concerns PG2/Art Itow
Mr. Itow presented information on the Early Ammonia Servicer and whether the 1" QD vent tool is required, and if so, whether its use is feasible. Recent issues with EAS QD seals required design changes that require pre-charging jumper hoses with gaseous N2 instead of ammonia for launch. The GN2 must be vented, and a 5 psi back pressure valve prevents venting through the EAS NH3 venting circuit. There are two options for accomplishing this. One involves adding a bleed hole in the EAS NH3 vent circuit; the second involves using the 1" male QD vent tool.
There has been a long-standing concern with the male QD vent tool, since to use it requires mating a free female QD to the free male QD. Soft docking is not a concern, but throwing the bale may be difficult. The worst case pressure at mating is 80 psig, which does not affect the force required to mate the QD.
The crew office believes that the vent tool is operable, and recommended an informal NBL evaluation to confirm this. CB/Dave Wolf agreed to work with XA/George Guirgis to set up this evaluation and provide a final recommendation. However the vent tool requires significant overhead for the task, and if the bleed hold option is feasible, this is preferred for EVA efficiency. Mr. Itow agreed to continue pursuing this option.
Decision: The EVA AIT recommended that pending final NBL evaluation, either EAS venting options are acceptable, however the preference is to incorporate a bleed hole in the EAS NH3 vent circuit to avoid the overhead involved in using the vent tool.
Actionee: XA/George Guirgis, CB/Dave Wolf
Due Date: November 28, 2000
Method for Closure: Report to EVA AIT
5. EVA standard ICD status follow-up discussion LMES/Mark Messinger, Viet Truong-Cao
Boeing PGs, Boeing-Prime
The following documents the current PIRN status as reported at the EVA AIT:
- 67B: Revision B comments are due November 16
- 71A : Approved by all parties
- 72 : In revision by Huntington Beach — agreed to document the interface in the EVA ICD, will investigate how energy absorber performance requirements are documented.
- 73: Canoga Park disapproved; Lockheed is reviewing the comments and may issue a revision.
- 74: Canoga Park disapproved; Lockheed is reviewing the comments and may issue a revision.
- 75: Huntington Beach is still reviewing in Vehicle Integration
- 76A: Revision A comments are due November 16. Canoga Park reviewed and provided comments to the original PIRN, no one present knew whether revision A included the CP comments. Lockheed will review the CP comments against Rev A and will determine if Revision B is required.
- 77: Approved by all parties
- 78: Approved by all parties
PIRN 79 is prepared and ready for submittal to the ICWG.
The EVA AIT then discussed action 553. Mr. Messinger and Mr. Truong-Cao reported that the gold-anodized handrail load requirements are documented in the EVA ICD, and that clear anodized handles are not considered handrails, only handles used for object handling. The assumption was that the clear-anodized handrails only support EVA handling loads. The handrail load requirements are different for the primary path handrails than for the secondary path handrails (less for shear/tension). This difference came about when the handrail load flight data was obtained and it was proposed that the load requirement be increased. Since this happened after many of the secondary paths were defined and assessed, an increase to the requirement was cost prohibitive. The two load requirements were accepted as a compromise, and the assumption was that the crew would be more careful when operating off the secondary paths. The EVA AIT requested crew and MOD evaluate the difference between the primary and secondary path load capabilities, since there is no visual indication that they are different. Additionally, the EVA AIT requested confirmation that the crew is trained accurately on the clear anodized handrail limitations.
Action Item Closure: AI-553 was Closed
Actionee: DX32/Bob Adams, Chris Looper, CB/Dave Wolf
Due Date: November 28, 2000
Method for Closure: Report to EVA AIT
Action 567: Initiate PIRN to EVA ICD to document the requirements for clear anodized handles/handholds
Actionee: LMES/Mark Messinger
Due Date: December 12, 2000
Method for Closure: Report to EVA AIT
6. Upcoming Events/Future Agenda Review XA/Nancy Patrick, All
Ms. Patrick reviewed the preliminary EVA AIT agenda for November 28, 2000. Presenters were requested to confirm agenda topics by COB Tuesday, November 21.
The Following topics were deferred until November 28:
Thermal Assessment of EMU Temperature Range B-Hou/Ryne Baker,
ES/Marie Kowal
Present impacts to ISS if acceptable EMU temperature range is held to -145°
F to +240°
F — provide assessment of which parts of ISS exceed this range most of the time. Propose a temperature range that will allow ISS tasks with extended EMU contact most of the time.
Decision Required: Information only
Required Attendees: XA, Boeing-Houston, DX32, CB, NC, EC5, KSC/SSHIO, PGs, SLP, MSFC
Action Item Closure: 546
UMA interference during CAS deploy — status of PG1/Dave Anderson,
PG1/ISS assessment of options and impacts Lisa Adams
Present charts for VSIP, addressing PG1 assessment of various options for resolving the interference issue, including launching UMAs in place and removing prior to deploying the CAS’s, and launching the UMAs separately and installing after CAS deploy. Provide recommendation for resolution and future plans and forward work for developing a final resolution.
Decision Required: EVA AIT concurrence with VSIP recommendation
Required Attendees: XA, Boeing-Houston, DX32, CB, NC, KSC/SSHIO, PG1, SLP,
