Status Report

Minutes for October 16, 2001 EVA AIT

By SpaceRef Editor
October 16, 2001
Filed under , ,

To: Distribution


From: XA/Nancy J. Patrick


Subject: Minutes for October 16, 2001 EVA AIT

The EVA AIT met at the Johnson Space Center on October 16, 2001. Boeing/David Read and XA/Nancy Patrick co-chaired the meeting. Representatives from CB/Flight Crew Operations, XA/EVA Project Office, DX32/EVA Systems/Mission Operations, NT/Flight Systems Safety and Mission Assurance, Boeing-Houston, (EVA, T&EC and Safety) and Boeing-Canoga Park were present. Representatives from the Kennedy Space Center, Marshall Space Flight Center, LMES, and Boeing-Huntington Beach supported by telecon. Copies of presentations can be obtained from XA/Bill Rollins Building 1, room 657, (281) 483-1416.

1. Introduction/AI Review Boeing/Dave Read


XA/Nancy Patrick

The Following Decision Packages were distributed for review October 20, 2001:


NCR-PG1-062: Commercial and Purchased Parts — Integrated Truss Segment S0



The Following Decision Packages were dispositioned (distributed October 2, 2001):


ESA-CUP-006: Cupola shutter: EVA handling load application point


Decision: This PIDS exception was approved



Review the following for concurrence/issues originally distributed June 19, 2001, last discussed October 2, 2001):


PG1-P3-2001-1 Rev C: SARJ Launch Restraint and EVA Bolt Break Torque Requirement


7/24, 8/7 and 10/2 Status Summaries:


  • Reviews confirmed that installation torque is recorded during element assembly, and therefore a limited flight hardware demonstration of break torque is acceptable

  • There is a significant savings from not testing S3 bolts, and because installation torques are recorded, testing of S3 is not required when the hardware design is the same as P3

  • SARJ Launch Restraint bolts have a locking patch that has an open issue that it wears out after several uses. Until this issue is resolved and the design is finalized, the SLR bolts will not be exempted from any verification requirements. Mr. Larsen confirmed that the SLR bolts were the only ones addressed by the PIDS exception that have the locking patch (they are now removed from this PIDS exception and will be processed in a separate exception when the issue is resolved)

  • There was a significant problem with the SARJ Launch Restraint MLI cover bolts during a demonstration on the Structural Test Article. Until this issue is resolved and adequate rationale is provided that no flight hardware demonstrations are required, the SLR MLI cover bolts will not be exempted from any verification requirements (they are now removed from this PIDS exception and will be processed in a separate exception when the issue is resolved)

10/16 Review: Revision B of the PIDS exception was presented, and it does not include the exceptions for the SARJ Launch Restraint MLI covers and the SARJ Launch Restraint bolts that are affected by the locking patch issue. An additional concern surfaced because the new EVA removable Clevis features (added to the design to resolve the UCCAS deployment interference issue) were not addressed by the PIDS exception. Therefore there is no documented requirement for verification of the clevis features since the change provides an exception to the testing requirement for all S3/P3 hardware and specifies how each item will be verified. Mr. Larsen agreed to revise the exception to provide for flight hardware demonstrations of the clevises, however noted that Huntington Beach will want to address the clevises and the SLR bolts and SLR MLI bolts in a future exception. The EVA AIT agreed to entertain those discussions when the rationale is available to discuss the specific requests for exceptions.

Decision: The PIDS exception was further revised (Rev C) and approved out of board. Revision C modified the exception to include flight hardware demonstrations for the new EVA removable Clevis hardware added to resolve the UCCAS deployment interference issue.

The Following Action Items were reviewed:


AI-577: This action remains open and will be addressed again on November 13. There was no report.


AI-620: This action remains open and will be addressed again on November 13. There was no report. EC/Tim Bond was added as an Actionee.


AI-637: This action remains open and will be addressed again December 11. Mr. Larsen reported that he submitted a PR (PR-BHB-MBS-P014) against the MBS MCAS guide vanes, and will submit a PR against the S3 and P3 guide vanes by mid-December. See minutes below for additional information.


AI-638: This action was CLOSED. Mr. Anderson reported on the controlling sharp edge design and verification requirements. Mr. Anderson also reported the method Huntington Beach is using to address the sharp edge concerns that are not covered by the existing requirements. See minutes below for additional information.


AI-644: This action remains open and will be addressed again on October 30. Investigations are still in work and the label process proposal is going forward in the next two weeks. See minutes below for additional information.


AI-645: This action remains open and will be addressed again on October 30. Investigations are still in work and the label process proposal is going forward in the next two weeks. See minutes below for additional information.

2. NASDA HTV RCS Thruster EVA Translation OM/Quan Le


Path Interference Waiver Request


Mr. Le provided information on the HTV thruster configuration. For control purposes, the preferred thruster location results in intrusions to the EVA translation path along Node2 and the JEM. This portion of the translation path allows the crew to translate to Node 2, JEM, CAM, Columbus and PMA2. Mr. Le explained that the options for relocating the thrusters to a non-interfering location involve significant cost ($3-$5million). A lower cost option ($1million) still intrudes somewhat into the EVA corridor and also results in HTV controllability concerns. Mr. Le and others have reviewed all the EVA requirements on the modules that require this translation path, and there are no tasks that have to be performed while the HTV is present. The only identified tasks that would use this translation path are replacement of the Node 2 heat exchangers, and the TCS team has confirmed that if a heat exchanger fails, replacement is not time critical and can wait until after HTV departure. Mr. Le provided the following rationale for acceptance of the existing thruster configuration:


  • The ISS plan is that HTV is docked for 2 weeks at a time (max of 3 weeks for a contingency), twice a year

  • The HTV is berthed to ISS by the SSRMS or JEMRMS and the thrusters are turned off prior to RMS capture

  • Thrusters are 2 fault tolerant to inadvertent firing

  • There are no schedule EVAs that require this translation path while HTV is present, and documented maintenance and contingency EVAs can wait until after HTV departure

  • If we do end up having to conduct maintenance or contingency EVAs on these modules with the HTV present, other methods for translation can be used (crew on SSRMS or alternate translation path)

  • HTV thrusters are being designed to meet EVA inadvertent contact loads should we decide to use this translation path with the HTV present


Significant discussion not included in the presentation material:


CB/Joe Tanner asked about the possibility for contamination from these thrusters, given the recent issues with thruster contamination on the Service Module. Mr. Le indicated that the Safety Review Panel had approved the thruster configuration and fuel from a contamination perspective, however he didn’t have detailed information about the review. The EVA AIT agreed that since the thrusters are turned off prior to RMS capture, and are two fault tolerant to inadvertent firing, this is not a driving factor in the decision to accept these thruster intrusions. Mr. Le agreed to provide the contamination information to Mr. Tanner off-line.



Decision: The EVA AIT concurred the HTV thruster configuration and approved the EVA translation corridor intrusions. Mr. Le still has to provide formal waiver/exception paperwork, which will be done in the future.

3. S0 Crew Squawk S0-037 – Pinch point between PG1/Jon Bonuan


S0-P1 fluid jumper and S0-P1 fluid QD male bracket


Mr. Bonuan presented information on the S0-P1 fluid jumper line installation area. Where the fluid QD attaches to the fluid line, there is a very tight clearance to QD panel A513, the fluid QD male bracket. The concern documented in the crew squawk is that during installation, this could be a pinch point for the EVA crewmember. Mr. Bonuan reported that MOD, JSC VITT and the Boeing Integration Test Team reviewed the fluid jumper installation operations and concluded that the pinch point is not a concern if handling of the jumper and QD is controlled, and that training can ensure that this is done.



Significant discussion not included in the presentation material:


The EVA AIT concluded that the pinch point concern does not really apply to this area. The act of putting the jumper/QD in place is the only action resulting in a pinch point, and if the crewmember starts to make contact he can control the contact by backing off and reconfiguring his grip on the jumper. The pinch point concern really applies more to moving mechanisms or lever-type hardware that can result in a pinch point during actuation or rotation.



Decision: The EVA AIT approved closing Crew Squawk S0-037 concerning the S0-P1 fluid jumper and S0-P1 fluid QD male bracket pinch point concern. The area is not considered a pinch point hazard and no label is required.

4. MCAS Guide Vane Sharp Edge Issue Status PG1/Larry Anderson, Roger


Larsen


Report status of PRs against MCAS guide vanes (Roger Larsen to initiate) and present Huntington Beach interpretation of EVA sharp edge requirements, design verification method for meeting the requirements (prior to swatch testing), and report how the MCAS guide vanes went through that process.

Mr. Larsen reported that a PR was submitted against the MBS MCAS guide vanes (PR-BHB-MBS-P014, AKA PR-PC-5-004579-000), however due to restrictions of the PR system, a separate PR would have to be written against the guide vanes on the other UCCAS guide vanes on S3 and P3. Mr. Larsen reported that the PR also includes other issues on the MCAS, and it would not be closed until all those items are worked. Mr. Larsen reported the guide vane bolt protrusion had been fixed with one of the approved sharp edge fix methods documented in the XA memo to the program on sharp edge testing and resolution. Mr. Larsen thought the bolt was covered with beta cloth tape, but he wasn’t sure. Mr. Larsen believed that he could submit the appropriate PRs against the S3 and P3 UCCAS guide vanes (total of 18 guide vanes) by mid-December.

Mr. Anderson discussed the sharp edge requirements (design and verification) and Boeing’s verification approach. Mr. Anderson explained that the requirements in 50005 allow for threaded ends of screws to extend up to .12 (1/8) inch. If they extend past that length, the requirements call for them to be capped, but there is no requirement to cover them if they are less than .12inch. The guide vane screws extend less than .12 inch, so Huntington Beach met the design requirements and verified that by drawing inspection, which is an acceptable verification method per that spec. The 07700 requirements only address corners and edges and there are no requirements specifying any verification method. The EVA AIT concurred that Boeing did in fact meet the documented sharp edge requirements.

Mr. Anderson further went on to explain that while Huntington Beach met the requirements, they realized that the requirements fall short of ensuring that no sharp edges exist, so Huntington Beach is conducting their own swatch testing of their hardware. They also plan to address any sharp edges found by swatch testing through one of the NASA approved fixes. Mr. Anderson explained that these guide vanes were scheduled for Huntington Beach swatch testing next month, and the issue simply surfaced before the swatch testing was done. The EVA AIT concurred that the Huntington Beach process will adequately address EVA sharp edge concerns.



Significant discussion not included in the presentation material:


PG2/Scott Boller asked if there was any thought to updating the sharp edge requirements to require covering any exposed threads. This is the intent of the existing processes and fixes, but it is not backed up by a firm requirement. The EVA AIT agreed that this would be a good idea for future elements, but too expensive to implement for hardware with baseline requirements. NT/Mirka Caro agreed to look into a requirements change that "grandfathers" hardware with baselined requirements.



Decision: The EVA AIT concluded that the existing Huntington Beach sharp edge verification and inspection process is sufficient for addressing sharp edges on their hardware. Sharp edge requirements need to be fixed for future external hardware.

Action Item Closure: 637 remains open, 638 was Closed.



Action 646: Determine whether and how existing EVA sharp edge requirements can be updated to eliminate sharp edges by design, and to include swatch testing as a verification method.


Actionee: NT/Mirka Caro


Due Date: December 11, 2001


Method for Closure: Present proposal to EVA AIT



5. Node 2 Touch Temperature Waiver/CR 5991 MSFC/Jack Stokes


Mr. Stokes reported that SSCN 5991 included a waiver request for Node 2 touch temperature violations. He has received direction that if the violations are encompassed by the temperature violations allowed by NCR-ISS-014 or NCR-XA-002, the SSCN is not required. The EVA AIT clarified that NCR-ISS-014 (if it is the same as NCR-PRIME-014, which the EVA approved for Node1 and PMAs) is not applicable to Node 2. That NCR was approved based on the operational requirements on Node 1 and the PMAs, which are not the same as those on Node 2. The EVA AIT concurred that no NCR or SSCN is required if the Node 2 temperature exceedances are enveloped by NCR-XA-002, however the exceedances must be documented in a hazard report with operational controls. The SRP controls the review of the hazard reports, and MOD and the crew office must agree to the operations controls before the hazard report is approved. Mr. Stokes reported that the exceedances are already documented in Hazard Report HR-0027. The EVA AIT concluded that no further EVA AIT involvement is required.

6. EVA label Squawk Resolution Process Proposal B-Hou/Dave Moore, Dave Read,


(Revisit from 10/2) XA/Nancy Patrick


Present results of investigation into whether the KSC TPS system can support adding labels after FCA. Present proposals for division of labor between Boeing and NASA to support both crew preference labels and ORU labels. Indicate timeframe when label requirements must be developed in order to ensure they can be installed prior to element closeout.

Mr. Read, Ms. Patrick and Mr. Moore updated EVA AIT members on progress since the 10/2 EVA AIT discussion. Ms. Patrick summarized a splinter meeting held on October 11. Boeing clarified that the process they are trying to institute is a no-cost change. Boeing wanted to streamline the label process and felt that they could pick up the additional work through the existing I&O budget and manpower. The splinter discussion also resulted in a proposal to use the new process for ORU labels in addition to label requirements identified through crew squawks. Boeing researched the work done to support S0 ORU labels and felt that they could accommodate the additional ORU label work within existing resources also (S0 work was to be covered by a separate CR). In summary:


ORU labels and crew squawk label requests would use the same process


Boeing-Houston, Boeing-Development Centers, and NASA will work together to develop and approve the label requirements and fabricate the labels


Boeing-KSC will install and document the labels implemented

The details of the process (how ORU information is provided, how the implementation is documented) are still in work by Boeing, however Boeing agrees to implement a process to install labels within existing resources. The EVA AIT will continue to work with Boeing to hammer out the details and will report back when the process is established.



Action Item Closure: AI-644, 645 remain open



7. EVA Standard ICD Status LMES/Mark Messinger,


XA/Dale Roberts, XA/Kristen O’Brien,


EC5/Lora Bailey

LMES/Mark Messinger:

The following status was reported:


*- 86: TM Curved Handrail Assembly — PIRN deleted — not standard hardware and it doesn’t belong in the ICD


*- 94: 3/16" Allen Driver — PIRN deleted — not standard hardware and it doesn’t belong in the ICD


– 96: Connector Tool: Work still on hold. Need to talk to EC/Joe Genzler to get latest status — need to get documented that the tool will fit the Boeing hardware.


– 97: Collar Release Tool: Work still on hold. Need to talk to EC/Joe Genzler to get latest status — need to get documented that the tool will fit the Boeing hardware.


– 98: EAS EVA Ohmmeter – Work deferred until new Fiscal Year – Restarting work next week


*- 99: Side Mounted Handrail Updates – Work deferred until new Fiscal Year — Restarting work next week


– 101: MT Energy Absorber Design Changes — 10/2 – signed by all parties — EVA AIT signed on 10/2


– 102: PGT — All parties signed, EVA AIT signed.


– 103: TERA Redesign — Boeing Prime requested changes and requested TBDs are resolved. Changes incorporated in Revision A, TBDs relate to TERA swing arm, which is being re-designed and is not flying on 8A (only TERA base launches on 8A). TERA base needs to be cleared up for 8A — Boeing to confirm they are OK with the TBDs that are in Revision A. An additional PIRN will be submitted in December to document the swing arm redesigned configuration.


– 104A: CETA Coupler – All parties signed, EVA AIT signed


– 105: CETA cover upgrade – All parties signed, EVA AIT signed


– 106: Node 2 Primary Translation Path —10/2 – signed by all parties — EVA AIT signed on 10/2


– 108: EVA Induced Loads — signed by all parties, EVA AIT signed


* Implies not identified as critical for upcoming Boeing FCA/PCA

 


XA/EC: Provide status of ICD issues provided September 18:


JZ-10: OTD loading exceeds maximum interface loads at WIF (EC/Lora Bailey, XA/Dale Roberts)


JZ-11: Inconsistent Handhold interface loads (XA/Kristen O’Brien)


JZ-13: Tool impact requirement on glass not updated per SSCN 821 (XA/Dale Roberts) (PIRN 108 resolved)


JZ-14: TDBs in SSP 30256 (MT-CETA rail profile and interface dimensions) (XA/Dale Roberts, EC/Lora Bailey


Ms. Patrick reported that XA had responded to all these ICD issues and was awaiting instructions on how to formally close them. OB/Brandy Cox agreed to provide direction on how to close the issues.

Ms. Cox reported that she is working on a revision to the EVA ICD to incorporate all the approved PIRNs. She requested direction on whether to wait for some of the remaining information on the TERA and CETA cart, which is to be delivered in December, or to publish a revision with the current approved PIRNs. The EVA AIT agreed that it would be better to wait until the TERA and CETA cart information is complete to capture the updates in one ICD revision.



8. Upcoming Events/Future Agenda Review XA/Nancy Patrick, All


Ms. Patrick reviewed the preliminary EVA AIT agenda for October 30. Presenters were requested to confirm agenda topics by COB Thursday, October 25.

PG2/Scott Boller reported that Incremental Design Review 1 (equivalent of a PDR) will be held November 14-15 for the SGANT, CMG and Battery FSE.



The Following Topic was deferred until October 30


Service Module MMOD Shield FSE handrail B-Huntsville/Tom Hagale


Clearance Violation


Present the MMOD Shield FSE handrail configuration and the concerns relative to handrail clearance. Present the operational scenario detailing when and how the handrails will be used. Provide waiver/exception rationale for review and consideration for approval.


Decision Required: EVA AIT concurrence with handrail configuration and request for waiver


Required Attendees: XA, Boeing-Houston, DX32, EC5, CB, NC, KSC/SSHIO, SLP,


SpaceRef staff editor.