Status Report

NASA STS-118 Execute Package FD03

By SpaceRef Editor
August 11, 2007
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NASA STS-118 Execute Package FD03

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15-0895: (MSG 018) – FD03 EVA Notes

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Rick, Dave & Tracy, we have a couple of last minute notes and reminders before EVA1 tomorrow. We’re looking forward to seeing you put all that training to work. Have a great EVA!

* Rick while translating underneath the MT/MBS there are some ungrounded connecters (issue briefed during quarantine). The connectors are ~ 2ft zenith of the UMA HRs you translate on, please stay nadir of the UMAs as you translate to avoid contacting these connecters.

* Tracy – we have uplinked the S1/S3 & P1/P3 Fluid Jumper Get Ahead Procedures (MSG 017 or ISS 15-0894). Please print it out and add it after 7-144 in the EVA FS. Priorities of get aheads have not changed; you are still go on the pre-flight list. Also, the EMU batteries launched in the EMUs have a lower total charge capacity than the ones currently on ISS. To take full advantage of having LiOH on EVA 1, we want you to swap to higher capacity batteries so that battery power will not be your expected limiting consumable. The batteries you remove will be used on EVA 2. We have provided you with an updated Consumables Tracking Cue Card which contains the new battery usage and recharge plan for the rest of the mission.

Dave – we have scheduled a 10 min block of time called “BATTERY CHANGEOUT” for the following updates. It is scheduled right after the EVA 1 Tool Config.

* Please tape the uplinked pages (MSG 016 or ISS 15-0893) to your current Consumables Tracking Cue Card

* Install EMU batteries for EVA 1 according to the new plan using ISS EVA SYS 1.515 EMU METOX/LIOH/BATTERY REPLACEMENT. As a reminder, the ISS batteries are in the “Batteries” mesh bag located in the Equipment Lock.

* For our ground based consumables tracking we will need to know the LiOH s/n’s that are in the EMU’s. When you swap the batteries, please call those down to us.

FD 1 Conjunction during Payload Bay Door Opening Timeframe:

While you were busy opening the payload bay doors on FD 1, the MCC Ascent Team was monitoring a conjunction with a spent Delta rocket body that was in a 952 nm x 165 nm elliptical orbit with perigee just below that of the orbiter. The normal pre-launch screening process which evaluates the shuttle trajectory through two hours MET was executed per the normal MCC and USSTRATCOM procedures. This rocket body trajectory was cleared for launch and was outside the criteria that would have required the launch time to be adjusted to the next even minute.

After the OMS-2 burn was executed, the Ascent FDO passed the updated orbiter state vector to USSTRATCOM per standard procedures. After the standard USSTRATCOM evaluation process, which typically takes a minimum of 40 minutes to execute, a conjunction with the closest approach occurring at 0/01:34 MET was reported. The total miss distance was 2.3 km with a very close predicted radial miss of 0.1 km. The MCC received notice from USSTRATCOM approximately 14 minutes prior to this close conjunction. Because of the large uncertainty in the orbiter state vector in this post OMS-2 timeframe along with the limited time to plan and clear a maneuver, a burn was not performed.

On FD 2, a best estimate of the orbiter trajectory was developed using state vectors obtained from rev 2 orbit determination. Based on these state vectors the actual miss distance was 0.6 km in the radial direction with a total miss distance of 1.2 km. This reconstruction places the conjunction outside of the criteria for which the crew would be notified and for which a maneuver to clear the conjunction would be executed. This is not surprising based on previous studies of OMS-2 navigation accuracy, which were discussed by the Ascent Team on FD 1.

In fact, we have always known there is a vulnerability to changes in conjunctions in the post MECO and post OMS-2 timeframe because of the inherit navigation errors associated with accelerating the launch vehicle to orbital velocities and establishing the initial post OMS-2 orbit. Once a valid orbit state vector is available on rev 2, the orbit process is not subject to these errors, so this scenario is not applicable for the remainder of the STS-118 mission.

Steve Stich STS-118 Ascent/Entry Flight Director

During a ground analysis audit of ISS power jumpers, the Oxygen Generation System Sec Pwr jumper connector shells were found to not provide proper fault bonding. This improper fault bonding could allow the connector shell to become energized and become a shock hazard.

You will not have any nominal operations that bring you in contact with this jumper, but we wanted to be sure you were aware of the issue. If DAUI troubleshooting is performed, MS-5 and FE-2 should use care when working in this area. ISS Crew is aware of the issue.

SpaceRef staff editor.