Minutes for April 10, 2001 EVA AIT

To: Distribution

From: XA/Nancy J. Patrick

Subject: Minutes for April 10, 2001 EVA AIT

The EVA AIT met at the Johnson Space Center on April 10, 2001. Boeing/Dave Read 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, OM/ISS Mission Integration, OC/ISS Operations Office, Boeing-Houston (EVA and Safety), Boeing-Canoga Park (EVA), LMES/EC5 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/Bill Rollins, Building 1, room 661, (281) 483-1416.

1. Introduction/AI Review Boeing/Lou Ramon

Mr. Ramon announced that B-Hou/Mr. Dave Read would be taking his place as the Boeing EVA AIT co-chair. All present expressed their gratitude to Mr. Ramon for his years of service to ISS EVA, and their deepest regrets to Mr. Read for the indescribable pain that lies ahead for him.

ESA-Cup-05: Side shutter — FRGF EVA release envelope

7A.1 Fit check matrix update — EVA AIT participants were asked to review and provide comments to DX32/Rich Gauvreau by April 24.

S0-001-2001: S0 CET Spur EVA Bolt Head Dimensions (Mr. Ramon reported that these undersize bolts had been reviewed and approved by EC/Roger Schwarz)

NCR-PG1-062: Commercial and Purchased Parts

NCR-PG1-056: Trailing Umbilical System (TUS) Interface Umbilical Assembly (IUA) Corners and Edges

NCR-PG1-042: ITS S0 MT Rail Corners

The Following Decision Packages were reviewed and dispositioned immediately (see minutes below for additional information:

ESA-Cup-03 (SSCN 03788A): EVA 125lbf kick load on Cupola Shutters

Decision: The EVA AIT approved this exception and corresponding SSCN (Note: NC/Stacie Greene requested that the exception be re-worded to say that the kick-load requirement does apply but is not met, however the ISS process dictates that the requirement not apply rather than be waived. Ms. Patrick approved the exception and asked Ms. Greene to coordinate with the SSCN CE to provide acceptable language in the SSCN instead).

ESA-Cup-04: Top shutter — top handrail envelope violation

Decision: This PIDS exception was approved

NCR-PG1-024: UHF Antenna Sharp Edges and Corners

Ms. Patrick received confirmation that the SVITO sharp edge inspection was complete, the only issue identified had been resolved, and MOD, Crew and Safety representatives then concurred with the NCR off-line.

The EVA AIT then held a brief discussion of an issue concerning the S0 keel stowage location PIP pin. SVITO/Kevin Flautt identified a concern with the PIP pin, as documented in crew squawk S0-045. The PIP pin holds the keel pin in its stowage location and is attached along the primary translation path along the truss. With the current installation location and tether length, the tether or ring could be snagged, causing inadvertent release of the PIP pin and thus release of the entire the keel pin. This protrusion was previously addressed in a PIDS exception approved by the EVA AIT on October 26, 1999, S0-44-1999: S0 EVA Translation Paths. The tether currently installed does not meet the minimum length required per the drawing. Mr. Flautt identified three possible solutions to the concern: Lengthen the pin tether, relocate the tether tie-off point, and use of wire ties to secure the tether better from its existing location. The first two options allow changing the PIP pin insertion point to the inboard side of the stowage bracket. Huntington Beach has already assessed lengthening the tether and the impact is significant due to the tools and process required to lengthen an existing tether. Changing the tether attach point has not been assessed, and use of wire ties is not an impact to Boeing, but requires additional on-orbit time.

The EVA AIT agreed to evaluate the wire tie option through the S0 EVA IPT. If that is found to be acceptable, there probably won’t be any justification to pursue any option that involves an impact to Boeing hardware delivery schedules or cost. There won’t be any NBL runs available until this summer to evaluate this option. Subsequent to the EVA AIT, Ms. Patrick requested that Huntington Beach investigate the impacts to incorporating the tether attach point relocation option, and to identify any schedule drivers to implementing that change. Ms. Patrick was concerned that waiting until NBL evaluations are complete may be too late to incorporate a fix that may be cheap and easy if done now. The following action was assigned:

Action 598: Determine the impacts of moving the S0 keel pin PIP pin tether attach point, and identify any schedule milestones that may drive us to making a decision by a certain date

Actionee: PG1/Larry Price, Jon Bonuan

Due Date: April 24, 2001

Method for Closure: Report to EVA AIT

AI-556: Evaluate the 7A and 7A.1 flight EVA tasks (including critical maintenance tasks available) against the allowable temperature range for EMU extended contact (-145°F to +240°F). Report any tasks that require extended contact that exceed this range, based on the EC thermal analysis provided. (DX32/Bob Adams)

This action remains open and will be addressed again on April 24. Mr. Adams is still reviewing the data available.

AI-581: Report status of PG1 WSA funding request for use of PRDs to mate truss segments (PG1/Larry Price)

This action remains open and will be addressed again on April 24. Mr. Price reported that the funding issue is to be discussed at the Mechanical IRB on April 11. Mr. Price did not know who was responsible for securing funding for the task if the IRB decision is that additional funding is required.

AI-584: Provide additional information on the software patch to fix the radiator accumulator cross-wiring issue – include impacts of updating the software during a planned software load. (PG2/Scott Boller)

This action was CLOSED. Mr. Boller reported that the problem is with firmware, and therefore a software patch does not really fix the problem. However the issue is really only after the first failure is sustained. The EVA AIT concluded that, based on the NBL testing completed, the EVA task to install the jumpers is acceptable. (Crew Consensus Report is pending, however CB EVA AIT rep reported that CB approves the task). EVA will work with the program to implement the jumper option if the program decides the jumpers are required.

AI-585: Confirm Chit has been submitted that documents specific response required for an ammonia leak in the current radiator cross-wired configuration for ISS real time operations (PG2/Scott Boller)

This action was CLOSED. Mr. Boller reported that Chit 165 (STS-97/4A) documented the immediate response required in the event of a failure.

AI-590: Determine whether the PVR meets sharp edge requirements for the surfaces to which the crew is exposed for the PVR center attachment fitting workaround, and whether the SSRMS can hold the PVR in place without slipping for the workaround. (B-Hou/Curt Carlton)

This action remains open and will be addressed again on April 24. Mr. Boller reported that SVITO planned a sharp edge inspection on March 27, however no one present knew the results. Mr. Boller reported that the worst-case force that would be input to the SSRMS is 93 in-lbs, well below the SSRMS limit for back driving, so that part of the task is not an issue.

AI-591: Determine if the RJMC 6B box workaround proposed during KSC installation task (to use only center bolt) is acceptable for all 6B boxes for on-orbit operations (PG1/Larry Price)

This action was CLOSED. PG1/Melanie Hodges reported that use of the center bolt only is not acceptable for most 6B boxes. The RJMC 6B box does not use the 6B box base plate as a thermal sink, therefore it does not require considerable contact with the base plate to maintain adequate temperature. The only other 6B boxes in this category are he TVCIC and the ACBSP 6B boxes. All others require the other bolts unless they are specifically exempted.

AI-592: Determine when NBL testing can be performed for segment-to-segment berthing using PRDs (DX32/Bob Adams)

This action was CLOSED. Mr. Adams determined that the current NBL mockups are not of sufficient fidelity to evaluate these tasks. If the program determines the tasks are required, DX32 will address upgrading the mockups through the DX CCB.

AI-594: Provide worksite analysis/graphical support for SSAS contingency bolts for remaining segments (all other than S0) (PG1/Berta DeLeon, Larry Price)

This action remains open and will be addressed again on June 26, 2001. Ms. DeLeon provided worksite analysis for all the segments, however she utilized WIF locations on the incoming elements, since this is acceptable if three of four of the bolts are engaged. EVA requires better direction on the failures for which the program wants to protect to determine whether this assumption covers all cases. Since this requires direction from the Structures and Mechanisms team, which is currently trying to address design of the primary SSAS system, no further action can take place at this time. In the mean time, EVA will continue to evaluate options using WIF locations on the already present element as time permits.

AI-597: Develop list of worksites that use the TM to evaluate whether there is an interference concern similar to the MTS strut bolts (PG1/Larry Price, Jon Bonuan)

This action remains open and will be addressed again on April 24. Mssrs. Price and Bonuan reported that they completed their review of worksites and only the S1/P1 radiator ORU worksite looks to be a tight clearance. They will complete a detailed review of this worksite and report results.

2. EMU Extended Contact Thermal Issue HSMS/Vicky Margiott,

LMES/ John Iovine, ILC/Scott Cupples, Mike Pantaleano, Maria Garza, DX32, CB

Ms. Margiott reported that the EMU extended contact temperature analysis was near completion, and results to date indicate that the EMU can be re-certified to at least a range of -100ºF to 240ºF, as was previously hoped. Ms. Margiott reported that the updated EMU thermal model was validated and used for the latest analysis. This model takes into account an EMU scrim adhesive melting temperature of 230ºF. (ILC determined that the previously reported melting temperature of 215ºF was conservative and they are able to sign up to the 230ºF limit). The EVA AIT concluded that the re-certification will be tracked by the EVA CCB, however the EVA AIT will assume the -100ºF to +240ºF range for remaining open work.

The EVA AIT then addressed the open work remaining to close out issues and provide adequate documentation for on-going ISS operations. The following documents the conclusions and open work to which we agreed.

• The EVA AIT concluded that an acceptable heat transfer rate is required for the EMU. This is based on the report that much of ISS met the touch temperature requirement by falling within the acceptable heat transfer rate requirement. Until we can be sure that the EMU constraints are enveloped by the existing requirements, we can’t be certain that all hardware that could pose a problem has been or will be identified in NCRs. No one present knew the status of the heat transfer rate identification, and Ms. Patrick and Mr. Iovine agreed to contact LMES/Grant Bue.


• The EVA AIT agreed that once we understand the allowable heat transfer rate, we need to review the previously approved NCRs and add the appropriate information to identify when EMU extended contact is a concern. EVA AIT team members agreed to a standing meeting on Wednesday mornings at 9:00 to review and determine changes required to the NCRs. The meetings will continue until the NCRs have all been reviewed. B-Hou/Joe Thomas agreed to consolidate the NCRs into a package for team members.


• DX32/Bob Adams agreed to review the current findings and plans for documentation with the MOD community and confirm that they are satisfactory for on-going ISS operations. Mr. Adams will address the flight rules required and any other operations documentation proposed.


• The EVA CCB must pursue EMU re-certification to the now defined allowable limits.

The EVA AIT agreed to present the issue status to the EVA CCB on April 20, with the current conclusions, plans and recommendations. After the EVA CCB presentation, the EVA AIT will adjust future work plans based on the CCB review.

Action 599: Determine acceptable heat transfer rate for the EMU for extended contact operations

Actionee: LMES/Grant Bue, HSMS/Vicky Margiott

Due Date: April 24, 2001

Method for Closure: Report to EVA AIT

Action 600: Coordinate EMU extended contact discussion with the Flight director office to review existing limits and planned documentation to determine if the data available satisfies operations requirements

Actionee: DX32/Bob Adams

Due Date: May 8, 2001

Method for Closure: Report to EVA AIT

Action 601: Consolidate EVA touch temperature NCRs to facilitate EVA review to include EMU extended contact resolution results

Actionee: B-Hou/Joe Thomas

Due Date: April 24, 2001

Method for Closure: Report to EVA AIT

Mr. Gaspar represents Huntington Beach System Safety for the S0/MT segment. Mr. Gaspar presented an issue uncovered during Huntington Beach’s review of the MT RSU LSAR input submitted by Spar. Mr. Gaspar reported that in order to change out an RSU, the MT has to be in "translate mode" (i.e. not latched down to a utility port). When not latched, both of the RSUs and the LDU are required to maintain structural integrity to sustain an inadvertent EVA contact. With one of the RSUs removed (the case for the R&R), the MT can only sustain up to 90lbs before loss of structural integrity (i.e. MT separates from the rails). Additionally, the proposed configuration relies on frictional forces to maintain structural integrity, which PG1 safety has determined to be risky.

Mr. Gaspar proposed that, during RSU remove and replace, the crew uses a tether to tie down the MT between either the CETA handrail or the Tether shuttle and the LTU. Mr. Gaspar requested EVA AIT concurrence with using the tether to close out the LSAR safety issue.

Significant discussion not included in the presentation material:

The EVA AIT questioned other aspects of the R&R procedure that are related. The EVA AIT first questioned whether the MT could even translate if one RSU was down. Translation is required to move the MT to a port where the SSRMS could walk off to a PDGF, since the SSRMS is required to support the EVA R&R task. The EVA AIT was also concerned that the MT has to be unlatched for the R&R, since that means removing power to the MBS. If the MBS extension cord (SSCN 4634) is provided, the power cord can be installed prior to when the MT is unpowered (or at least immediately afterward). Then the R&R task would not be time constrained to the time available when the MBS can remain unpowered. Since the MBS unpowered time could be as low as 2 hours, the EVA AIT was not comfortable with a time constraint on the R&R time. The EVA AIT also questioned whether unlatching the MT is even required for the RSU R&R. Mr. Gaspar also reported that there is some question as to whether the MT meets the inadvertent contact load requirement, and if not, by how much. Spar’s position is that they meet the load requirement. Ms. Patrick suggested that Mr. Gaspar review the Spar analysis and conclusions with ES/John Zipay establish an ISS program position.

The EVA AIT noted that the tether operation requires a significant amount of analysis and additional development work before EVA can definitively conclude that we can meet the hardware requirements. Included in that list is:

• What are the requirements for the tether — what tension is required, how is the tension verified?


• Does an existing tether meet the MBS/MT stability requirement?


• Where specifically should the tether be routed, and are there any structural concerns with the attach points


• Does the MT have to be moved away from the utility port for the RSU task? If not, can the tether be attached prior to unpowering the MT to minimize the unpowered time?

The EVA AIT concluded that use of a tether is probably workable if required, however before a significant amount of work is expended, the ISS program should address whether unlatching the MT is really required, and whether there are other concerns with unlatching the MT that would drive you to another solution. The EVA AIT requested that Mr. Gaspar consult with OM/Skip Hatfield and the MSS IPT prior to any conclusion that tethering the MT is required. Ms. Patrick also requested that Mr. Gaspar consult with ES/John Zipay to determine the whether and how much the MT violates the inadvertent contact requirement since that was a question as well. Mr. Gaspar agreed to pursue those avenues prior to a formal request to implement installing the tether.

Decision: The EVA AIT concluded that if the ISSPO determines it is required, an EVA tether option is probably feasible for cinching down the MT during RSU R&R to meet the inadvertent contact load requirement. The EVA AIT requested an MSS IPT and a Struc and Mech position prior to initiating efforts to develop the details for the tether option.

Action 602: Present MT RSU R&R inadvertent contact and proposed MT tether to OM/Skip Hatfield and ES/John Zipay to determine ISSPO position on RSU R&R operations (whether MT has to be/should be unlatched and whether tether is required for RSU R&R)

Actionee: PG1/Nick Gaspar

Due Date: May 8, 2001

Method for Closure: Report to EVA AIT

Action 603: Investigate whether MT has to be unlatched to provide EVA access to RSU or LDU for R&R

Actionee: DX32/Bob Adams, Michelle Hollinger

Due Date: May 8, 2001

Method for Closure: Report to EVA AIT

Ms. Knotts described the EVA workaround procedure developed for the Lab MMOD shields prior to 5A. The procedure enables removing the shield in the event a Dzus fastener was splayed during a previous shield installation activity. This has happened on shields on the ground and the fastener has to be drilled out and replaced. CB/Joe Tanner reported that there is at least one splayed fastener on one of the Node 1 shields, however there are no further planned removals for that shield. The Node 1 shield mounting interface is different, and therefore much more susceptible to splaying than the shields on other elements.

Ms. Knotts explained that the procedure developed requires prying the shield off using the ISS pry bar. The pry bar is leveraged against the wire tab nut plate, which is attached to a structural beam, in order to pry off the shield at the splayed fastener. MLI covers are placed over the shield to contain any debris generated. The team also evaluated using the ISS bolt puller and determined that is an adequate backup for the pry bar. MOD, XA, Safety, EC and the 5A crew participated in development of the procedure and approved it. They considered several issues during the evaluation, including inadvertent release of the bar while prying, projectiles from the tangs, force required to free the fastener, and tool requirements. The team determined that inadvertent release of the pry bar was not a concern because it would not result in impact if it occurred. The MLI cover would contain any potential projectiles, and the crew can generate the force necessary. No new tools are required — the pry bar and bolt puller are sufficient. Ms. Knotts indicated that the procedure has been reviewed for possible use on 6A and is in place to implement in real time if required. For future ISS operations, the procedure will be added to the generic portion of the ISS EVA procedures.

Significant discussion not included in the presentation material:

The EVA AIT asked for specifics about the MLI blanket to be used. Ms. Knotts explained that there are many options in on-orbit stowage bins, and that it is not necessary to specify which blanket should be used. Any number of blankets in several locations would be acceptable, and the flight crew/ops team can choose whichever blanket is convenient for them for the particular application. The EVA AIT concurred with Ms. Knotts’ recommendation.

The EVA AIT concluded that, pending approval from Structures and Mechanisms, the procedure is sufficient and no further work is required to assess it. The EVA AIT requested formal approval from Structures and Mechanisms that the prying action required is allowed on the structure. Ms. Knotts agreed to coordinate with ES/John Zipay for concurrence.

Decision: The EVA AIT concurred with the proposed contingency MMOD shield removal procedure for a splayed Dzus fastener

Action 604: Review the splayed Dzus fastener/MMOD shield contingency procedure with ISS Struc and Mech to confirm procedure is allowed.

Actionee: DX32/Kerri Knotts

Due Date: May 8, 2001

Method for Closure: Report to EVA AIT

Mr. Dickson presented and requested approval for the following Cupola PIDS exceptions:

ESA-Cup-03 (SSCN 03788A): EVA 125lbf kick load on Cupola Shutters

ESA-Cup-04: Top shutter — top handrail envelope violation

ESA-Cup-05: Side shutter — FRGF EVA release envelope

Mr. Dickson reported that the cupola shutters don’ t meet the inadvertent kick load requirement when in the open position. The shutters are generally closed except when viewing is required to support operations, or when the crew is working on the cupola due to a failure. Mr. Dickson reported that if kicked, the shutter is no longer functional but there is no risk of sharp edges or breaking off hardware. Mr. Dickson suggested that the shutters could be closed when an EVA crewmember is translating past the cupola to control the hazard. If the crew is working on one of the cupola windowpanes, the adjacent shutters can be closed to control the hazard, therefore only the shutter on the window on which you’re working is at risk. ESA added handrails on the top of the cupola to assist in crew stabilization to further minimize the risk. The EVA AIT concurred that the risk is low, and the impacts are small if it is kicked, therefore the EVA AIT approved ESA-Cup-03.

Note: NC/Stacie Greene requested that the exception be re-worded to say that the kick-load requirement does apply but is not met. The ISS process dictates that the requirement not apply rather than be waived, therefore a PIDS exception has to state that the requirement does not apply. Ms. Patrick approved the exception and asked Ms. Greene to coordinate with the Mr. Dickson to provide acceptable language in the SSCN instead.

Mr. Dickson explained that due to the shape of the cupola, the handrails on the top do not meet the handrail clearance requirement at the ends of the handrail. EVA AIT members agreed that the violation is minor and the handrails provide sufficient functionality for required operations. ESA-Cup-04 was approved.

The EVA AIT briefly discussed the FRGF EVA release envelope. There was not enough graphical information in the package to evaluate the release envelope violation, so the EVA AIT requested the normal 2-week review process for this exception. This will allow review of the exception request with personnel that are more familiar with the Cupola hardware. Mr. Dickson agreed to provide better pictures illustrating the work envelope and violation as well.

Decision: ESA-Cup-03 (SSCN 03788A), and ESA-Cup-04 were approved. ESA-Cup-05 was deferred until April 24 for further review.

6. EVA Solar Array Rotary Joint (SARJ) Trundle Tool Boeing/Dave Gallinger, Roger Larsen

Mr. Larsen and Mr. Gallinger presented a new tool requirement for removing and replacing a SARJ Trundle. They reported that the trundle was not designed to be either removed or installed under axial load. Attempting to install a new trundle on-orbit, with the worst-case axial displacement between the race ring halves, would result in significant force required to install it and would risk damage to the trundle (galling of spherical washers or yielding/galling of the retainer). On the ground, a jack has been used to control the ring-to-ring spacing to control the axial load. Huntington Beach proposes use of an EVA installed tool to maintain ring spacing to allow trundle removal and replacement.

Huntington Beach has some conceptual ideas for the required tool. They propose initiating a CR to the ISSP to design, build, test and certify the new tool. Huntington Beach plans to generate the CR/SSCN. They requested EVA AIT concurrence on the tool requirement and guidance on the tool development process.

Significant discussion not included in the presentation material:

The EVA AIT deferred to the ISS program with regard to the need for the tool. The EVA AIT then discussed the process for tool development. The EVA AIT requested that in addition to the tool itself that the CR/SSCN provide for manifesting, on-orbit transport and stowage, and NBL mockups. In addition, the EVA AIT requested that EVA personnel be informed of and allowed to participate in the design process to ensure EVA requirements are addressed. CB/Joe Tanner noted that a tether point should be added to the current tool concept and that double height EVA bolts should be used.

Huntington Beach asked whether the EVA community wanted to take over the tool design and build, similar to what was done for the Locking Strut. Ms. Patrick agreed to get an XA position on that, however noted in her opinion it’s better handled by the Struc and Mech team, since the requirements for this tool are very system specific and system-critical, and the EVA interfaces are minor. ES/Guy King will work with Huntington Beach to initiate the CR to develop the tool.

Action 605: Provide EVA Project Office position on whether EVA should manage the design and build of the EVA installed Trundle tool (required to maintain race ring spacing during trundle remove and replace)

Actionee: XA/Nancy Patrick

Due Date: April 24, 2001

Method for Closure: Report to EVA AIT

Ms. Patrick reviewed the preliminary EVA AIT agenda for April 24, 2001. Ms. Patrick requested that presenters confirm agenda topics by COB Thursday, April 19.

The following topic was deferred prior to the EVA AIT, pending conduct of the OM TIM

Report results of ISSPO TIM to address integration issues with ORUs, FRAM and large EVA tools (CETA, OTD and TERA). Report actions assigned and status as available. Report future plans to address the incompatibility.

Decision Required: None at this time — information only

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