ISS MER Management’s Daily Notes Thursday, June 14, 2001 – 12:00 pm
The following notes highlight the ISS activities within the last 24 hours that were discussed during the morning NASA and Boeing management teleconferences, as well as the daily MER Management & Subsystem Tag-Up. These notes are not intended to provide the current configuration of the ISS systems, nor are they intended to capture all of the events that have occurred in the past 24-hour period or that are planned for the next 24-48-hour period. For a detailed overview of the last 24-hour period and upcoming ISS events, refer to the “0800 Report” and “Daily Report”, published by MOD on its Mission Control Center (MCC) website at http://mod.jsc.nasa.gov/mcc (select “Realtime Mission,” then “ISS Msgs”).
EAS and Spare SASA Connectivity Issue: During a recent MOD SIM, a design configuration problem for 7A.1 was identified. On 7A.1, the Early Ammonia System (EAS) will be installed on the P6 truss. The EAS has 2 Y-Jumper cables that will be installed to route operations and heater power to the spare SASA. Power is routed from 2 RPCMs, each on different power channels, to provide redundancy. Either operations or heater power is adequate to maintain the spare SASA within thermal limits. The problem identified is that the jumper will cause the SASA and spare SASA to be placed on the same bus, and each have the same RT address. As a result, if the spare SASA is powered on (done to maintain thermal), the prime and spare SASA’s will try to talk on the same bus, which could immediately cause a loss of communications to the ground and possibly a 1553 bus failure. An ART has been formed and met yesterday to discuss potential resolutions, with emphasis on trying to support the early August launch date for Flight 7A.1. Preliminary resolution options discussed by the ART include pulling the cable pins to prevent 1553 connection to the spare SASA; developing short jumpers that don’t have 1553 connection pins so that the existing 50-ft cable doesn’t need to be modified (maintains its full capability for other uses later during assembly); don’t make operations power connectivity. Further definition of the options is underway and they will be presented at today (June 14) at the ISS Daily.
SSRMS: To perform additional troubleshooting of the SSRMS JEU Remote Terminal (RT) addressing anomaly, a new software patch (Patch #3) was uploaded yesterday, June 13. Several attempts were made through the late morning and afternoon to upload the patch, which consists of 2 separate computer files, but the ground experienced difficulties in getting the 2nd computer file to upload properly. Successful upload was accomplished late in the afternoon and power cycling of the redundant string was performed. The transmit/receive error did not recur, so further diagnostics to isolate the problem could not be performed. The upload problems appear to have been the result of a ground commanding ground commanding problem, in that the command server would not properly access the JSC. This morning, plans are to remove Patch #3 and at around 10am CST begin performing the Airlock Dry Run procedure using the SSRMS’s redundant string, which is the string that is currently planned for use during airlock installation on Flight 7A.
BGA 4B Rotation: The 4B array was placed in rate mode this morning. Since the rotation testing that occurred earlier in the week did not result in any high-current events, the current plan is to monitor 4B while it is in rotation and, should a high-current event occur (>0.5-amp for >10 min), the troubleshooting tasks called out in the original test plan will be initiated. For clarify, a new CHIT was developed to clarify when and what procedures should be performed now that the array is remaining in rate mode for more than a set number of orbits.
ESP-1 Heater Issue: The MER ART will be supporting Boeing-Canoga Park’s presentation to the VSIP today (scheduled for 3pm) regarding the potential impacts to the spare DCSU and PFCS that were exposed to cold temperatures beyond the –45 deg F acceptance test limit when the ESP-1 heaters were inadvertently powered off for ~31 days after Flight 6A. The presentation will also address where the ART stands in making a determination in whether to replace the spare ORUs. Plans are to formally transition the ART to a SPRT at the VSIP. Two PRACAs to address the ORU temperature exceedances (i.e., one per ORU) were issued yesterday. A new IFI has been issued to address why one of the four DCSU heaters on ESP-1 did not activate when all of the ESP-1 heaters were commanded back on.
Service Module Batteries: Maintenance remove & replace activities for the SM batteries is planned for today. Specifically, SM Batteries 2 and 6 will be swapped out. SM Battery 6 is degraded and the PTAB for battery 2 is non-functional. By swapping the batteries, the Battery 6 location should become fully restored.
BP/ECG Power Trip: An ART has been established to investigate problems encountered yesterday during activation of the CHeCKS BP/ECG. As reported yesterday, after the BP/ECG was plugged into a UOP, the UOP tripped. The BP/ECG power cable was replaced, but the UOP tripped again when the BP/ECG was plugged back into it. A diagnostic self-check was performed on the UOP and no problem was identified. The BP/ECG was plugged into a different UOP, which then tripped. A new IFI was established and the ART was formed to investigate the root cause and try to identify potential workarounds. (This was reported in yesterday’s daily notes, but wasn’t discussed during the morning teleconferences. Therefore, it is being repeated since it was discussed at today’s morning teleconference.)
Ku-Band Auto-track Anomaly: Prior to performing a TDRS handover on the Ku-Band system last night, the Ku-Band was operating nominally. The command to configure Ku-Band back to auto-track mode was given and accepted. As expected, the system transitioned to open loop slew and began the spiral acquisition sequence. The TD171 forward link signal was found during the spiral search and the system transitioned to acquisition lock state with a PWRL of –47 dB. The PLC state transitioned from reset to normal momentarily, but then transitioned back to reset, so the Ku-Band transmitter output power remained at zero. The Ku-Band Antenna was neither near a mask nor did the PWRL value drop below –51 dB at any time after the initial acquisition sequence. The system remained in auto-track mode and continued to track TD171 forward link until the end of the TDRS event. The PLC state remained in reset for the entire event. During the next Ku-Band opportunity, system was commanded back to auto-track and it began to function properly. A new IFI is being established to investigate this issue. (This was reported in yesterday’s daily notes, but wasn’t discussed during the morning teleconferences. Therefore, it is being repeated since it was discussed at today’s morning teleconference.)
Progress Thruster Firing Test: After transitioning back to XVV from XPOP yesterday morning, the Russians attempted to fire the primary Progress thrusters as part of a planned Russian Thruster Firing Test. The thrusters fired, but quickly shut down. The information provided by the Russians are that a high-pressure reading for Manifold 1 was obtained, which caused the shutdown. Switchover to Manifold 2 occurred, and the thruster firing was then performed successfully. Investigation into the firing anomaly is ongoing and a new IFI has been generated.
Leaking Collapsible Water Containers (CWCs): The crew reported yesterday afternoon that some of the CWCs were exhibiting slow leaks. Five (5) CWCs were found to have mildew on them, but only one bag was determined to actually be leaking (Number 5093). The crew treated the mildew yesterday and will do so again today. Procedures call for the leaking CWC to be emptied, which should occur today.
Node 1 Smoke Detector: The Smoke Detector ART met today and recommended that the Node 1 Smoke Detector #2 remain powered but not enabled through next week to gather more data on the obscuration scatter characteristics. Over time, the obscuration scatter readings have gradually increased over time, even when the smoke detector was unpowered to allow troubleshooting of the electrical connections to be made. The obscuration data is still not high enough to falsely alarm smoke detection, but the team is not ready to recommend re-enabling the smoke detector at this time.
Payload MDM Power Cycle: Payload MDM PL-1 MDM shut down late yesterday. The FDIR shutdown the Payload MDM when it declared itself failed and automatically attempted to repower the MDM. The MDM successfully powered back up and is currently operating nominally. A new IFI has been issued and C&DH is investigating this anomaly.
New IFIs Generated Within the Last 24-Hours
MCA Purge Timer Override Failure and Loss of Synchronization with INT MDM
Progress Thruster Firing Anomaly
ESP-1 ORU Heater Failed to Come On
Leaking CWCs
Progress Thruster Firing Anomaly
Today’s Events (GMT 2001/165):
Airlock Dry Run Installation with the SSRMS
SM Battery R&R
Refresh of 3 RPCM EEPROMs that have Heath Status Flags (may slide to the right because of SSRMS ops)
Upload of the NCS PCU Non-Op Patch (may slide to the right because of SSRMS ops)
Upcoming Events for GMT 2001/166-168 (i.e., Friday, Saturday, Sunday):
Crew time has been allocated to support SSRMS operations on Saturday. Specific troubleshooting activities will be determined by the SSRMS ART today or Friday.
Other Upcoming Events:
CHeCKS BP/ECG ART – Thursday, June 14, MER Conference Room, 3-4pm
SSRMS ART — June 14, 11:00 am and 4:00 pm, MER Conference Room
ESP-1 Heater ORU Presentation to VSIP – June 14, Building 4S, Room 3419, ~3pm
MCA ART — Thursday, June 14, 1 pm (tentative – may be canceled)
Smoke Detector ART — Thursday, June 14, location and time TBD
Vacuum System ART — Friday, June 15, MER Conference Room, 2:00 pm
RWS ART – Friday, June 15, 1pm, Building 30, Room 2312
Tuesday, June 19 – Upgrade to new web-based IFI Database, ~3pm
