The Agency Flight Readiness Review (FRR) is still expected to slip STS-128\u2019s launch date by one day \u2013 to August 25 \u2013 due to additional pad flow work related to repairs on an ETVAS (External Tank Vent Arm System) ordnance cable. However, managers will meet again on Wednesday to set the launch date, as they all-but accept the risk assessment findings on the External Tank foam liberation concerns.<\/p>\n
STS-128 Processing Latest:<\/p>\n
As reported by this site over the past few days, two engineering challenges placed pressure on the pad flow towards a August 24 launch date, thus resulting in a one day impact to the schedule \u2013 still a major achievement due to the interruption to the processing milestones.<\/p>\n
Firstly, an issue with a Main Bus controller \u2013 specifically the Forward Power Control Assembly (FPCA-3) \u2013 caused a delay during weekend processing, ahead of a second problem relating to a cable on the ETVAS \u2013 which has resulted in engineers having to back out of S5009 operations for its repair.<\/p>\n
![\"DC2\"](\"https:\/\/www.nasaspaceflight.com\/wp-content\/uploads\/2009\/08\/DC2.jpg\" "\\"DC2\\"")
\u201cS5009, Final ordnance installation\/connections: IPR 63 to Pyro; During ETVAS power-off stray voltage check and connection at the GUCP (Ground Umbilical Carrier Plate), the voltage reading exceeded desired value,\u201d updated Tuesday processing information on L2.<\/p>\n
\u201cTroubleshooting led to the replacement of the power cable on the GUCP. Ordnance disconnects were completed this morning (Tuesday) in support of retest. Once retest is complete, ordnance will be re-connected and S5009 operations (Run 3) will be finished.\u201d<\/p>\n
As of late on Tuesday, the cable had been repaired, allowing engineers to proceed with \u201cS5009 ordnance install\u201d to pick up at 21:00 local time.<\/p>\n
While FPCA3 retests continue \u2013 though main retests are complete with no issues found \u2013 engineers are looking into the specifics of the failed hardware, in order to determine what caused the issue. This is also involved in the FRR\u2019s flight rationale discussions.<\/p>\n
Space tourism guides (adsbygoogle = window.adsbygoogle || []).push({});<\/p>\n \u201cPicked up an IPR (Interim Problem Report) of the FWD PCA #3 last week,\u201d added the latest Shuttle Standup\/Integration report on L2. \u201cDid some troubleshooting on the PCA (Power Control Assembly). Over the weekend, got the R&R and most of the retest done. Still have a little of the retest to complete.<\/p>\n<\/p>\n \u201cThe contactor has been removed from the FPCA. It is in the lab. Boeing-Engineering is performing failure analysis on it. The guys did a great job of getting it apart and starting the FA (Failure Analysis) on it this weekend.<\/p>\n \u201cThe part of the contactor that was failed turned out to be the Y2 lead, which is similar to the one talked about before, except this was in the OFF position. Some of the differences were that this one failed at the root where it was staked in, and that there was no solder bump present.<\/p>\n \u201cThere is more metallurgical analysis ongoing. How this will work into flight rationale, and what might have to change, and how to respond to this failure are all TBD (To Be Determined) right now.\u201d<\/p>\n Once back into the regular pattern of processing on Tuesday evening, engineers will finish the closeouts of the orbiter for flight, as the mission closes in on S0007 Launch Countdown operations.<\/p>\n \u201cS1287, Orbiter aft closeout began over the weekend and will continue today (Tuesday),\u201d added processing information. \u201c50-1 \/ 2 door installation and Post Aft Confidence Test are scheduled for Thursday night. S0007.100, Launch Countdown Preparations, continue.GO2 recharge is scheduled for today.\u201d<\/p>\n FRR External Tank Discussions:<\/p>\n Three main areas of foam loss were observed during the ride to orbit, with the focus on two \u2013 an LO2 Ice Frost Ramp (IFR) and the liberations from the intertank.<\/p>\n Samples of the adhesive \u2013 taken during the pull tests \u2013 have been sent to the Michoud Assembly Facility (MAF) for testing, as the root cause of contamination \u2013 likely dust \u2013 finding its way on to the surface of the tank during their production in New Orleans continues to be the leading theory as root cause.<\/p>\n This also holds the potential of clearing all downstream tanks, should the contamination be confirmed as a one-off incident.<\/p>\n \u201cET-132: Did the 18 pulls on the +C side, they all looked good. Had one pulled with \u2018thin, fuzzy film\u2019, a little better than 56 psi,\u201d added the Standup report. \u201cHad one that pulled adhesively at a little better than 53 psi (very similar to the adhesive pull on the -C side that was ~54 psi). The adhesive swabs are being hand-carried back to MAF.\u201d<\/p>\n The reason managers are taking longer than usual to conclude the Agency FRR relates to the amount of data that has been collated on the foam loss issues since the incident with ET-131. As of the start of this week, additional data was still lacking \u2013 as noted by the Chief Engineer (department) at the Johnson Space Center (JSC).<\/p>\n \u201cHad some follow-on meetings to talk about foam. The main topic, from a SSP (Space Shuttle Program) standpoint, was the ET foam. Talked through the three different aspects of it: bipod, intertank, and IFR,\u201d the standup continued.<\/p>\n \u201cThere is still some concern there (IFRs), and folks want to recommend doing the NDE (Non Destructive Evaluations) as a technical recommendation. From a void standpoint, have a lot more confidence that we understand the void size and distribution. We still have some uncertainties in the release timing.\u201d<\/p>\n Tomorrow\u2019s additional day of meetings for the Agency FRR is not expected to take all day, with approval all-but secured on the risk assessments to favor approval for launch, as opposed to a rollback to the Vehicle Assembly Building (VAB) for modifications to the IFRs.<\/p>\n However, the amount of time spent debating the tank left a few outstanding items for the FRR to discuss, which will be completed on Wednesday morning.<\/p>\n L2 members<\/em><\/em>: Documentation \u2013 from which the above article has quoted snippets \u2013 is available in full in the related L2 sections, now over 4000 gbs in size.<\/em><\/em><\/p>\n","protected":false},"excerpt":{"rendered":" The Agency Flight Readiness Review (FRR) is still expected to slip STS-128\u2019s launch date by one day \u2013 to August 25 \u2013 due to additional pad flow work related to repairs on an ETVAS (External Tank Vent Arm System) ordnance cable. However, managers will meet again on Wednesday to set the launch date, as they […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":"","_links_to":"","_links_to_target":""},"categories":[2],"tags":[3610,9205],"class_list":["post-41020","post","type-post","status-publish","format-standard","hentry","category-news","tag-frr","tag-sts-128"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/41020"}],"collection":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/comments?post=41020"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/41020\/revisions"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=41020"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=41020"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=41020"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}See Also<\/h4>\n
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![\"DC3\"](\"https:\/\/www.nasaspaceflight.com\/wp-content\/uploads\/2009\/08\/DC3.jpg\" "\\"DC3\\"")
As reported on Monday, the final set of pull tests on Discovery\u2019s External Tank (ET-132) have shown no issues, as the adhesive properties between the foam and the tank\u2019s structure appearing to be well within limits.<\/p>\n