Minutes for November 13, 2001 EVA AIT

The EVA AIT met at the Johnson Space Center on November 13, 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, EC/Engineering Crew and Thermal Systems, OC/ISS Operations Office, OM/ISS Mission Integration Office, and Boeing-Houston, (EVA and Safety) were present. Representatives from the Kennedy Space Center, LMES, and Boeing-Development Centers (Huntington Beach, Huntsville, Canoga Park) supported by telecon. Copies of presentations can be obtained from XA/Donna Ezzell building 1, room 641, (281) 483-6771.

1. Introduction/AI Review Boeing/Dave Read

NCR-PG1-031: Coldplate Radiator Fin Edges

NCR-ISS-062: Plasma Contactor Unit Two-Fault Tolerance Noncompliance for Flight 12A.1

8A/S0 Fit Check Matrix Update — Comments should be sent to DX32/Jaime Strandmark and XA/Maria Tullar before November 27.

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

Decision: This NCR was approved

Note: The Following SMDP/TDK/FSE NCRs originally distributed indicated a flight applicability of UF-1 rather than UF-2. The NCRs were corrected for this error only but not distributed again prior to the EVA AIT.

NCR-TDK-01: TDK Pinch Points

Decision: This NCR was approved

NCR-SMDPTDKFSE-01: SMDP-TDK FSE Handrail Spacing

Decision: This NCR was approved in principle and will be signed after it is updated to reflect a decision (coordinated with the UF-2 EVA IPT) to delete the aft handrail on the FSE. The crew and MOD lead determined that the aft handrail will interfere with stowing the TDK, and that the aft handrail is not required for operations. They requested that the aft handrail be removed. Boeing agreed and the NCR will be modified to reflect the change.

NCR-TDK-02: TDK Violation of Orbiter Camera Envelope

Decision: This NCR was approved

The Following Action Items were reviewed:

AI-577: This action remains open and will be addressed again on January 8. Mr. Gafka did not report. B-Hou/Dave Read reported that Huntington Beach is preparing a position paper on the subject to be delivered to NASA and it should be released soon.

AI-620: This action remains open and will be addressed again on February 5. Ms. Patrick reported that during a vent tools stowage discussion on November 9, Mr. Bond reported the plan for re-certifying the fluid QDs that will exceed their certification temperatures during normal planned operations. Mr. Bond reported that the S0 tray fluid QDs will see temperatures beyond their certification and that a test plan is in work to expand the certification temperature limits. Mr. Bond estimated that the testing would be complete and results in within 3 months (although formal re-certification will require several more months). The vent tool in question will be enveloped by the testing planned and will be included in the re-certification.

AI-633: This action remains open and will be addressed again on January 8. Mr. Bonuan reported that the stress analysts will have to analyze the case and they don’t yet have a schedule to do so. They reported that probably more than 25ft-lbs will be required, however it will be less than the installation torque of approximately 60-80 ft-lbs. Ms. Patrick noted that only the inboard bolts should be considered for less than 25ft-lbs, since the torque multiplier will be fit on the outboard bolts. Mr. Bonuan will provide that information to the stress team to see if it will result in a more favorable torque requirement.

2. UF-1 MPLM FRGF Contingency EVA Boeing-KSC/Ken Koby

Mr. Koby requested a waiver to the SSP 50005 requirement for 1" clearance around bolts for the MPLM FRGF Contingency EVA bolts. Mr. Koby reported that during a fit check on the UF-1 MPLM (FM-2), the Micrometeroid Debris Panel Shield (MDPS) interfered with installing the EVA tool for bolt release (Box end ratchet wrench). When Mr. Koby inspected the MPLM, he adjusted the MDPS shield to provide more clearance for the tool, however they still don’t meet the 1" clearance requirement. The fit check was redone and the ratchet wrench fit, however the SVITTO requested a waiver because they were concerned that the shield could move during ascent loads and result in the same interference.

Mr. Koby provided two versions of the waiver — one that covers UF-1/FM2 only, and another that covers all the MPLMs for all flights. Mr. Koby noted that measurements were taken on FM2 from the bolt to the shield, after adjustment, and reported that the minimum clearance from either the upper or the lower bolt is .343 inches. Mr. Koby reported that these clearances were compared against the MPLM tolerances and that the FM2 minimum clearance is the minimum on any MPLM. During the fit check, with the tool installed, the clearance measured from the outer edge of the tool to the shield was .219 on the lower bolt and .281 on the upper bolt. Mr. Koby and CA/Betsy Ahearn reported that there is some compliance in the shield, such that the tool can probably be forced on even with hard interference with the shield.

Significant discussion not included in the presentation material:

The EVA AIT addressed the tool tolerances and the tool used for the fit check. The tool used was not the UF-1 flight unit, but rather one temporarily stored at KSC for SVITTO use for fit checks and other hardware demonstrations. CA/Betsy Ahearn agreed to provide the serial number for the tool used so that it could be compared to the UF-1 flight unit. This information would decide whether the UF-1 flight unit would fit on the UF-1 MPLM. XA/Margaret McPhail agreed to provide the worst-case tool dimensions to determine whether any tool would fit on any MPLM to address the global waiver request. However DX32/Bob Adams reported that the box end ratchet wrench is the tool used when the SRMS is grappled to the FRGF, but it cannot be used when the SSRMS is grappled because of the larger footprint of the SSRMS end effector. Mr. Adams reported that the wobble socket with a 6" extension should be evaluated if the SSRMS is to be used. No one present knew whether an SSRMS grapple must be protected for UF-1 but all agreed to determine this. The EVA AIT members agreed to work on the UF-1 related information off-line with the goal to provide an answer by the end of the day, and that the global waiver request would be addressed in the next two weeks with a decision at the next EVA AIT.

When the EVA AIT discussed why the MPLM bolt clearance violation was not addressed during formal verification, there was no clear answer. No one present (nor anyone in the EVA project office) saw any formal EVA verification paperwork. Mr. Koby reported that when he tried to research the question, he received information that the task received an acceptable rating in an NBL test and therefore it was assumed to be acceptable. The EVA AIT noted that NBL testing is not adequate for verifying or accepting tight tool clearances, since NBL mockups and tools are not built to that level of fidelity.

The following documents the conclusions reached after the EVA AIT that led to signing the UF-1 waiver on November 15:

Ms. McPhail determined that the tool in question is a commercial, off-the-shelf tool purchased for this purpose from Snap-On tools. Because it was purchased commercially, dimensional specifications are not readily available within the Engineering Directorate. Ms. McPhail found that the typical Snap-on tolerances for tools of this nature are ±
. 02". Ms. McPhail worked with EC5 to obtain a measurement on another Class 1 tool in EC5’s position and determined that its outer diameter was .91". Assuming the standard tolerance range, and assuming the tool measured is on the low end of the range, the worst-case diameter tool would be .95". A tool of this diameter would fit on the bolt, given the clearances reported. Ms. Patrick and Ms. McPhail discussed the situation with XA Hardware Group Lead/Glenn Lutz, and all agreed that the waiver is acceptable for UF-1 based on the following:

• Based on standard Snap-On tool tolerances, and a measurement of a Class 1 unit, the worst case Box end ratchet wrench outer diameter should be no greater than .95"


• Based on the fit check performed, a worst-case clearance available is .291" with the tool installed, therefore the worst-case tool diameter should fit with at least .251" clearance.


• There is some flexibility in the panel such that the tool should be installed even if the clearance is reduced.

The EVA AIT noted that this issue surfaced several concerns with the fit check process. First, MOD did not specify or review which tool (part number) should be fit checked, to confirm that the SRMS or SSRMS cases were adequately covered (lack of a fit check matrix for SVITTO to use). Second, while a Class 1 unit was used for the fit check, it was not the unit that is manifested on the flight, which is a violation of the current policy to either fit check with the tools that could be used or a gauge. Finally, the hardware provider apparently used an NBL test as justification that the 1" bolt clearance violation was acceptable and did not process a waiver to meet formal verification of a known violation.

Decision: The EVA AIT concurred with the UF-1 waiver out of board on November 15. There is additional work to determine whether the waiver is acceptable for all MPLM flights.

The All flights waiver will be discussed at the November 27 EVA AIT, as will the questions about the fit check process and use of the NBL for verification of tool clearances. No formal actions have yet been assigned.

3. Vent Tool Bag Status, Request for location change EC5/Gary Nickel

Mr. Nickel presented the current status for the vent tool stowage bag development, including open issues that affect the bag design. Mr. Nickel reported that a Pre-PDR meeting was held on November 9 to review the requirements and open issues. At that meeting, decisions on bag direction were made pending completion of some assessments, analysis and vent tool certification issues. Mr. Nickel reviewed those decisions and the open work, and included the major assumptions and design drivers for the bag to confirm all requirements have been captured.

Mr. Nickel listed the tools that the bag will hold, which includes the vent tools, the QD release tools, the QD bail drive levers and the connector cap tools. Mr. Nickel reported that the bag might be either one or two bags, which will be driven by the designers based on the size constraints for taking the bags out through the ISS airlock, and real estate available at the installation site.

The external stowage location for the bag is also still undecided. The aft location on the equipment lock may not be feasible because of some structure between the trunnion pins and from the size constraints imposed by the distance available between the trunnion pins. The preferred alternative location is on the forward/zenith area of the equipment lock, however the thermal environment may not be compatible with the current tool temperature certification limits. The tool limits may be increased by virtue of other ISS QD problems, since the same QDs that are the limiting factor on the tools will see temperatures outside these limits in other locations. The QD Issue Resolution Team (QDIRT) is addressing these excursions over the next few months and the tools will be included in their assessments and subsequent waiver/re-certification efforts.

The only other significant issue driving the bag design is whether the ammonia tools have to be segregated from all the other QD tools so that neither the crew nor the tools are exposed to ammonia. This is being addressed by the safety organization. Previously, there was no identified risk or hazard control for the crewmember after use of the ammonia vent tool (per 5A operational documentation), so unless something has changed, crewmember exposure to a tool that has been used should not be an issue. The tool designers have stated that the tools are not at risk as long as the QD caps are installed when stored, so the tools should not be an issue either. However formal safety concurrence is required.

Significant discussion not included in the presentation material:

Mr. Nickel noted that the open work is not currently addressed in formal actions, however both he and XA/Greg LeStourgeon will follow them and do not require EVA AIT actions. The tool development will not be addressed further at the EVA AIT unless specific issues require an EVA AIT position.

Decision: The EVA AIT concurred with the current concepts for the Vent Tool Bag and the schedule and plans for the open work remaining.

4. NCR-PG1-062: Commercial and Purchased Parts B-Hou/Joe Thomas

Mr. Thomas presented an updated version of NCR-PG1-062, Commercial and Purchased Parts — Integrated Truss Segment S0. The parts included in the NCR include primarily screws, bolt threads, washers and similar parts used to assemble ORUs and install ORUs and secondary structure on the segment. The parts are used extensively on S0. The rationale for acceptance is that all the hardware will be inspected with swatch testing by Huntington Beach during the assembly process, and that any sharp edges identified will be fixed by one of the approved resolution methods documented in the sharp edge standard repair drawing 1F00352, until it passes the sharp edge inspection. If Huntington Beach were to decide that it was too much of a cost or schedule risk to fix a sharp edge, and the risk is small to fly as is, they will process a separate NCR to accept the hardware.

Decision: The EVA AIT approved NCR-PG1-062.

5. EVA Hex Head Bolt Spring Suspected Condition PG2/Scott Boller, Doug Aiken

Mssrs Boller and Aiken presented information on a SCAN recently generated for some of Canoga Park’s EVA fasteners. The fasteners use a coil spring to provide separation when the bolt is released. On one of the P4 fasteners on the Fluid Quick Disconnect Coupling (FQDC), personnel noticed that with the bolt engaged, the spring was protruding from where the bolt met the structure. The end of the spring was determined to be a sharp edge hazard when exposed in this manner. Canoga Park is in the process of addressing the cause of the failure and the proposed operational workarounds, since the fasteners were used on Z1 and P6 and are already on-orbit.

Mr. Aiken reported that the fasteners are routinely disassembled upon delivery from the vendor, to make modifications for different applications (e.g. lubrication is added). They become new part numbers when they are altered. Canoga Park initiated a search for all known fastener locations on Boeing hardware that is already on-orbit. Huntington Beach reported that the fastener was not used on any of their hardware on-orbit, and Huntsville had not responded yet. Mr. Aiken and Mr. Boller provided a list of all the Canoga Park locations on Z1 and P6, along with an indication of the level of risk associated with each fastener. The fastener was designated "red" if it is used for a scheduled task or near a translation path, "blue" if it is used for maintenance or contingency task only, or "green" if it represents no potential hazard (not near a translation path and not used for any identified assembly or maintenance task). Mr. Aiken and Mr. Boller also provided drawings indicating the location for all the Canoga Park fasteners.

Finally, they provided a proposal for inspecting fasteners on-orbit, and tracking any that have the condition. They proposed that crews be informed of the potential hazard and briefed on the fasteners that they could encounter either by translation or task. For fasteners that have to be used that are identified as being in this condition, they provided an anomaly resolution plan. The resolution plan proposed requires partially releasing the fastener, removing the spring and re-engaging the fastener, or applying tape to cover the hazard.

Significant discussion not included in the presentation material:

Mssrs. Aiken and Boller reported that the cause of the failure appears to be that the fastener was disassembled and when it was re-assembled, the spring was not adequately seated in the retention groove on the housing. Mssrs. Boller and Aiken didn’t believe that simply actuating the bolt, if it is assembled correctly could induce the failure. The EVA AIT also asked about the process by which Boeing is closing the issue with the ISS Program, and which NASA boards are reviewing the complete closure. Mssrs. Boller and Aiken weren’t familiar with the detailed plan for the issue, only that they were assigned a chief engineer’s action to report the information provided to the EVA AIT. Mssrs. Boller and Aiken agreed to look into the issue closure plan and provide as much as they could find out at the next EVA AIT

The EVA AIT reviewed the fastener location provided and concurred with Boeing’s recommendations on the red, blue and green designations. Boeing proposed briefing crewmembers on all the red and blue fasteners identified, however since the UF-1 crew is close to flight with only one NBL run remaining in two days, the EVA AIT did not want to confound their training at the last minute without further definition of the hazard. The EVA AIT requested that Boeing review ground and on-orbit closeout photos to try to rule out as many of the fasteners as possible. Mr. Boller and Aiken agreed to provide as much of that information as possible by November 14.

The EVA AIT agreed to the following forward work plan:

• Boeing will review closeout photos (ground and on-orbit) for Z1 and P6 fasteners to determine whether some of them can be ruled out as hazards


• Boeing will add notes to OP-01 and LSAR procedures for any tasks that use the questionable fasteners, unless those fasteners can be ruled out as a hazard by the inspection process


• Boeing will present the detailed SCAN issue closure plan to the EVA AIT on November 27, including the NASA board responsible for closing the issue, schedule for closure, root cause information (especially if the failure can be induced by actuating a fastener that has been assembled correctly), status of data on Boeing-Huntsville on-orbit elements, status of closeout photo review for Z1 and P6, ground techniques to prevent the failure in the future and inspections to confirm no failures prior to launch, and ground tracking process for inspecting fasteners on-orbit and tracking those that are a hazard.

The EVA AIT reviewed the proposed anomaly resolution plan but did not feel that the specific procedure should be approved until a problem is found on-orbit. The EVA AIT had some concerns about trying to remove a spring if it is not seated properly since this could be more dangerous than leaving it.

Action 647: Present EVA fastener SCAN issue closure status (schedule and board for closure, root cause information, Boeing-Huntsville element data, closeout photo review for P6/Z1, ground techniques to prevent and/or catch failures on future elements, ground tracking process for inspecting fasteners on-orbit).

Actionee: PG2/Scott Boller, Doug Aiken

Due Date: November 27, 2001

Method for Closure: Present to EVA AIT

6. Fit Check Matrix Status DX/Bob Adams

Mr. Adams reported that he has not received an updated fit check matrix (updated to specify completed fit checks and results) and will report again on November 27. Ms. Patrick reported that XA leads confirmed that no fit checks have been completed on S3/P3, and the updated 8A fit check matrix was distributed earlier in the EVA AIT. Mr. Adams will provide an S1/P1 status at the next EVA AIT.

Action 648: Report status of 9A/11A fit check matrix, including completed fit checks and results. Indicate when FCM will be updated if it has not been.

Actionee: DX32/Bob Adams

Due Date: November 27, 2001

Method for Closure: Report to EVA AIT. Provide updated matrix if available.

7. EVA Standard ICD Status LMES/Mark Messinger

There was no presentation material for this topic.

– 96: Connector Tool: This PIRN was deleted — no connector tools identified other than bail drive tools and collar release tools, and they are covered by a different PIRN.

– 97: Collar Release Tool: Lockheed needs part number/CARD document number and will begin drafting PIRN from the CARD. XA/G. LeStourgeon provided information by email.

– 98: EAS EVA Ohmmeter — LMES drafted PIRN, sent to EC for review, no date for when EC will respond.

*- 99: Side Mounted Handrail Updates — LMES expects to have draft ready by 11/19 for Subsystem manager review.

– 103A: TERA Redesign — All parties concurred, EVA AIT chair signed out of board on November 9.

– 109A: JEM-PM Primary Translation Path to JEM-EF, ELM-ES, and Node 2 – No report on status – responses due November 16.

Waiver/PIRN requirement for 1.6" QD clearance requirement for the QD Bale Drive tools:

The EVA AIT concluded that there is no need for a waiver for this tool, since the QDs should meet the clearance requirement without the tool installed (if not, they should present individual QD PIDS exceptions). Violating the requirement with the tool installed is not an issue since the tool provides the interface to the QD and therefore 1/6" is not required (in the same way that no waiver is approve lack 1.6" clearance when a crewmember’s hand is grasping the QD).

OB/Provide status of ICD issues provided September 18:

JZ-10: OTD loading exceeds maximum interface loads at WIF: Still waiting program direction on whether additional information is required.

JZ-11: Inconsistent Handhold interface loads: Still waiting program direction on whether additional information is required.

JZ-14: TDBs in SSP 30256 (MT-CETA rail profile and interface dimensions): EVA AIT discussed slidewire to handrail minimum distance for JEM and whether 13.8" is acceptable (NASDA reported that will be the minimum distance). EVA AIT concurred that it is sufficient, suggested putting 12" in the ICD to allow pad for JEM designers (assumed maximum is 24", the maximum handrail spacing requirement). Still waiting program direction on whether additional information is required for the remainder of the issue.

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

Ms. Patrick reviewed the preliminary EVA AIT agenda for November 27. Ms. Patrick requested that presenters confirm agenda topics by noon, Wednesday November 21 if possible, and no later than first thing Monday, November 26.

PG2/Scott Boller reported that the MT/CETA rail delta CDR is currently scheduled for December 19 — 21 at Canoga Park, with a requirements review on December 18.