Status Report

Minutes for October 2, 2001 EVA AIT

By SpaceRef Editor
October 2, 2001
Filed under , ,

To: Distribution

From: XA/Nancy J. Patrick

Subject: Minutes for October 2, 2001 EVA AIT

The EVA AIT met at the Johnson Space Center on October 2, 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, ES/Engineering Structures, and Boeing-Houston (EVA and Safety) were present. Representatives from the Boeing Development Centers 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 16, 2001:

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

The Following Decision Packages were dispositioned (distributed September 18, 2001):

MSS-SNCR-021: OTCM Gripper (and front face) exposed edge and corner requirements (Spar Deviation D00026-B)

Decision: The EVA AIT approved this NCR

The Following Decision Packages were dispositioned (originally distributed June 19, 2001, last discussed August 7, 2001):

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

7/24, 8/7 Status: MOD was concerned that no testing was to be done on the S3 bolts, they would be accepted by similarity to P3 design (some subset of P3 bolts is being tested). The contractor wants to minimize the number of cycles on launch restraint bolts because they’ve had some problems meeting their final torque requirements because the locking patch becomes worn with repeated cycling. The contractor explained that they have experienced out of spec (high) running torques during installation, and have had to cycle the bolts a number of times to meet the running torque requirements, however additional wear due to cycling results in concerns in meeting the final torque required to sustain launch loads. There is no major cost or schedule concern with conducting the same level of testing on the S3 bolts, however the contractor was trying to minimize testing wherever possible. The EVA AIT was concerned that we may miss some S3 problems because we did not test any of the bolts (e.g. if S3 bolts came from a different lot than P3 and there was some problem with manufacturing that lot).

The EVA AIT recommended the following:

  • 7/24 – Determine whether installation torques are being recorded for all bolts. If this information is available, that will give some insight into higher than expected torques that may indicate a concern. (8/7 – Mr. Larsen provided sample installation procedures that indicate bolt torques are recorded during installation.)

  • Provide final closure rationale for the SARJ launch restraint bolt high torque and locking patch wear issue. The final issue resolution may affect our opinion on whether S3 bolt testing is required (PG1) (8/7 – No information was available on the locking patch wear issue and whether that affects the proposal to not test S3 bolts. Mr. Larsen reported that PG1/Bob Grimes and Roy Van Winkle are the leads for the issue, and he will request that they report their status on August 21)

  • Determine whether there is significant savings by not testing the S3 bolts (8/7 – Mr. Larsen reported that deleting the S3 bolts from required testing is a cost avoidance because 450 hours of procedure development and review work would be required to approve the 5 tests required. In addition, unique test configurations and rigging would be required (different from the P3 tests) to support the same hardware testing on S3.)

10/2 Status: Mr. Larsen submitted a revision to the exception that indicates that if the SARJ launch restraint design changes from what has already been tested, EVA testing must be completed on at least 1 unit of the new design (Item 1 in the Rationale section of the exception). This was to allow for the PIDS exception to be processed prior to resolving the locking patch issue. Mr. Larsen requested this because some of the other bolts are coming up in the assembly process, and without approval of the PIDS exception, testing will be required on those bolts which are not controversial. As a cost savings, Mr. Larsen requested the revised PIDS exception be approved.

The EVA AIT requested confirmation that the SARJ launch restraints are the only bolts affected by the locking patch issue. These are the only bolts referenced by the note added to allow for additional testing, and the EVA AIT wanted to make sure that no other bolts are also possibly affected.

Additionally, the crew office expressed concern over not testing the SARJ launch restraint MLI cover bolts. The crew experienced a problem with those bolts in an earlier test, where they could not be fully removed. Huntington Beach believes that the issue is included in a PR, and that the PR would address any design re-work and hardware testing required. Until that issue is resolved, the EVA AIT felt that an exception to those bolts should not be granted.

The EVA AIT agreed to process the exception if the SLR MLI bolts are removed from the exception (they will be processed in a separate exception and are not planned for near term testing), and if Huntington Beach confirms that the SLR bolts are the only ones affected by the locking patch issue. Huntington Beach agreed to revise the exception and re-submit it for discussion on October 16.

The Following Action Items were reviewed:

AI-618: This action was CLOSED. Mr. Bue and Mr. Iovine provided information in a briefing to DA8 that indicates the duration and frequency of violations of the EMU extended contact temperature constraints. The data they supplied indicated the temperature profiles throughout an orbit (at times prior to and after orbital noon), for various Beta angles and ISS attitudes. Specific analyses are required to evaluate the capability to perform an EVA on any given day, however the data provided by Mr. Bue and Mr. Iovine indicates that the temperature violations can be handled operationally, by either re-scheduling an EVA, or managing the exposure time by controlling when the crew works in any area that experiences violations during part of the orbit (e.g. operating only during a night pass, prior to orbital noon, etc.)

AI-635: This action was CLOSED. Mr. Schmidt provided the data from Boeing that indicates which operations use the RAD at the longest duration and highest speed. Mr. Schmidt noted that the number of turns required equates to twice that number of RAD turns for a given operation (for every PGT revolution, the RAD makes two). This information will be evaluated when the RAD constraints are better understood, expected to be in November.

AI-636: This action was CLOSED. Via email, MOD and the crew office reported that for the tasks listed, the OTD could either be temporarily stowed on the truss or an alternative WIF can be used for APFR operations on the CETA cart.

AI-642: This action was CLOSED. PIRN 102 was submitted and reflects the correct PGT accuracy.

2. O2/N2 Tank Latch Handle Proposal B-Hou/Dave Moore

Present recommendation for securing O2/N2 tank latch handles to prevent inadvertently moving the handles from the latched position by snagging them with EVA tethers. Indicate any Boeing analysis or evaluations pending to approve the procedure.

Mr. Moore presented a request to add an EVA get-ahead task to wire tie the two latch handles on the doghouse side of the O2/N2 tanks to the adjacent handrail hourglass. The wire ties will help prevent the latch handles from rotating from the "latched" to "ready" position should there be inadvertent contact. The wire ties won’t help keep an EVA tether snagging on the handles, but they will minimize the risk should a snag occur. Mr. Moore provided pictures of the proposed configuration and confirmed that he had coordinated the proposal with CB, XA and MOD. Mr. Moore noted that from that coordination, it appears that little crew training is required and it may be possible to fit the task in one of the 8A EVAs.

CB/Joe Tanner asked if the PIP pin that secures the handle could be inserted from the other side of the handle to perform the same function (the PIP pin tether is too long to keep the handle from rotating in the current configuration). Mr. Moore thought that it was possible, but didn’t know if the tether length will allow you to insert it in that configuration, or if you could, that it would then be short enough to keep the handle from rotating. The EVA AIT agreed that the appropriate approach would be to plan to secure the handles with wire ties, however the EVA crew could evaluate using the PIP pin in real time and possibly not use the wire ties. Mr. Moore agreed to work with XA/Steve Broussard to add the task and the wire ties to a flight manifest as a get-ahead task. The requirement will probably go to the RIP first.

3. EVA label Squawk Resolution Process Proposal B-Hou/Steve Smith

Present Boeing proposal for evaluating and coming to resolution on crew squawks on EVA labels.

Mr. Smith presented several options for dealing with an on-going issue with EVA labels. Boeing implements the labeling requirements per SSCN 549/SSP 50005, however since generic label requirements don’t always adequately cover specific hardware requirements, many labels are requested via "crew squawks". For Boeing to add new labels after FCA, whether they are required to meet requirements or not, authorization is required to change the hardware configuration via an Engineering Order and a drawing change is required to maintain the as flown configuration. This process is expensive and time consuming. Mr. Smith presented several options for providing EVA labels that are not in the current baseline, whether the existing labels meet the documented requirements or not. Mr. Smith presented the impacts for each of the options, including the impacts to Boeing to implement new labels, and the impacts to users for retrieving information on the labels. All of the options presented involve Boeing participation in the process, and therefore would likely require a change to implement, and therefore, it was thought, a cost to the program. The process involved EVA AIT technical approval of any labels requested through crew squawks, with implementation through the Daily Space Station Review (DSSR).

Option 1 consisted of using a TPS system at KSC and did not capture the as-installed label configuration electronically. Option 2 would utilize a new, to be built database that uses photo documentation and references to flight drawings to capture the as-installed label configuration. Option 3 uses the existing VMDB to capture the as-installed label configuration through a "Configuration Data" addition (no drawing updates). The baseline process is to formally update drawings. Boeing’s recommendation was to implement Option 2 to provide quick access to label information with minimal cost.

Significant discussion not included in the presentation material:

The EVA AIT discussed the options at length, and concluded that if any ISSPO cost is incurred by any of the new options, the program will likely not fund it. The EVA AIT questioned whether there is a way to implement some of Boeing’s proposals using only NASA resources. KSC/Mike Haddad thought that the KSC TPS system was tightly controlled and was part of the configuration management of the vehicle. He thought that once a TPS is approved and implemented, it would feed back into the vehicle configuration data. The EVA AIT felt that if the TPS is configuration controlled and contains the as-installed labels, we could provide a copy of the TPS to the flight control team to have ready reference to the label configuration. Mr. Haddad and B-Hou/Dave Moore agreed to look into the TPS system and determine whether and how it feeds the vehicle configuration data. One possibility would be to have the SVITTO generate the TPS and install the labels, however no SVITTO personnel were present and no one knew whether they have the resources to do that.

The EVA AIT also discussed streamlining the process for getting authorization to install labels. Mr. Read agreed to get the generic guidelines that the Boeing sites use for placement of labels (e.g. truss structure is OK for labels, thermal coatings are not, overlaying existing labels is OK, etc.) so that we can ensure that placement of new labels will not need significant analysis before we are authorized to install them.

Mr. Smith and the actionees agreed to report back on the status at the next EVA AIT.

Subsequent to the EVA AIT, on October 11, several of the interested parties met and further discussed the proposal. Boeing clarified that they were proposing this as a no-cost alternative to the existing process, rather than as a cost proposal. Boeing-Houston feels that they can implement the label requests using existing resources. Boeing-Houston would be the primary team responsible for developing the label requirements and getting them manufactured, and Boeing-KSC would install and provide documentation on how and where they were installed. The discussion identified several areas for additional work. The Boeing proposal did not include installing ORU labels. NASA/XA has been working on a process for ORU labels that involved a CR to identify label requirements, install them and provide updated documentation. All agreed that the most efficient thing for the program is to combine the two label processes, but that would probably result in a cost to the program (since a cost was expected for the ORU label implementation). This would also be better for consolidating all the installed label configuration information in one place for operators. XA/Jeff Dutton agreed to look at NASA support for part of the process (developing requirements for and manufacturing labels) for ORU and crew preference labels, and Boeing agreed to look at whether they could install the labels and document their placement within existing resources.

The holes to be worked out include responsibilities for non-Boeing elements, label installation on Boeing hardware that is "GFE" to non-Boeing elements, and Boeing support from the sites for generating ORU labels. Additionally, spares on-dock at KSC don’t have labels, and if a spare is manifested late there may not be time to install the label. Those present agreed that the process will have to go forward within a week to allow S0 labels to meet schedule, and these other issues will have to be addressed in the future.

Action 644: Investigate KSC TPS system and determine how a TPS is controlled, and whether a completed TPS updates the vehicle configuration data. Determine whether the TPS system can be used for installing and documenting labels.

Actionee: KSC/Mike Haddad, B-Hou/Dave Moore

Due Date: October 16, 2001

Method for Closure: Present to EVA AIT

Action 645: Provide generic guidelines and constraints for where and how labels can be installed without impact to Boeing vehicle certification — look at guidelines for installing on truss structure, MLI covers, existing label overlays, etc.

Actionee: B-Hou/Dave Read, Steve Smith

Due Date: October 6, 2001

Method for Closure: Present to EVA AIT


4. EVA ICD Update XA/Nancy Patrick

OB/Brandy Cox reported that the following PIRNs were signed by all parties and requested EVA AIT signature:

101: Update Section 3.10 to Reflect Design Changes to the MT Energy Absorber (MTEA).

106: Node 2 Primary Translation Path to JEM-PM

No objections were raised and Ms. Patrick signed the PIRNs.

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

Ms. Patrick reviewed the preliminary EVA AIT agenda for October 16, 2001. Presenters were requested to confirm agenda topics by COB Thursday, October 11. Ms. Patrick noted that the Label Process and Loctite on EVA bolts discussions would be added to the October 16 agenda.

The following items were deferred until October 16:

Use of Loctite on EVA Bolts — test results ES/Katherine Davis

Report results of loctite/bolt testing that was scheduled to be complete in spring, 2001. The purpose of the testing is to ensure that use of Loctite is acceptable on EVA bolts as a launch restraint, including EVA force requirements and usability of bolts after initial removal. (Related to action AI-522: "Report on the ISS program plans to resolve questions with the use of Loctite on EVA bolts. Include test plans and proposed completion dates." Closed on 12/12/00)

Decision Required: EVA AIT concurrence with test conclusions

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

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

Clearance Violation

Present information on the MMOD shield FSE handrails that don’t meet the handrail clearance requirement. Indicate when and how the handrails are needed. Provide waiver/exception for approval if possible.

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.