{"id":41415,"date":"2008-05-15T18:37:47","date_gmt":"2008-05-15T10:37:47","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/sts-124-frr-debate-outstanding-issues-faulty-mdm-removed-2\/"},"modified":"2008-05-15T18:37:47","modified_gmt":"2008-05-15T10:37:47","slug":"sts-124-frr-debate-outstanding-issues-faulty-mdm-removed-2","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/sts-124-frr-debate-outstanding-issues-faulty-mdm-removed-2\/","title":{"rendered":"STS-124: FRR debate outstanding issues \u2013 faulty MDM removed"},"content":{"rendered":"<p>Discovery\u2019s STS-124 mission remains on track, pending the satisfactory outcome of four issues \u2013 all of which are heading to the agency Flight Readiness Review (FRR) next Monday.\n<\/p>\n<p>  A successful re-test of Discovery\u2019s General Purpose Computers (GPCs), final confirmation that elbow camera clearances are within spec, a satisfactory status update of the Russian Soyuz investigation, and the on-time delivery of a CO2 scrubber are required to remain on track for May 31\u2019s launch dates.\n<\/p>\n<p><em><img fetchpriority=\"high\" decoding=\"async\" height=\"129\" alt=\"\" hspace=\"5\" src=\"http:\/\/forum.nasaspaceflight.com\/forums\/get-attachment.asp?action=view&amp;attachmentid=13910\" width=\"600\" align=\"left\" vspace=\"5\" border=\"0\/\"><\/em><\/p>\n<p><em>**The most comprehensive collection&nbsp;of&nbsp;Shuttle, Ares, Orion&nbsp;and ISS&nbsp;related presentations and mission documentation, plus expansive daily processing documentation and updates&nbsp;are&nbsp;<\/em><font color=\"#0000ff\"><em>available to download&nbsp;on L2<\/em><\/font><font color=\"#0000ff\"><em>&nbsp;**<\/em><\/font><\/p>\n<p><font color=\"#ff0000\"><em><img loading=\"lazy\" decoding=\"async\" height=\"139\" alt=\"\" hspace=\"5\" src=\"http:\/\/forum.nasaspaceflight.com\/forums\/get-attachment.asp?action=view&amp;attachmentid=31173\" width=\"212\" align=\"left\" vspace=\"5\" border=\"0\/\"><\/em><\/font><em><font color=\"#0033ff\">**Click&nbsp;here for sample of L2 menu and content**<\/font><\/em><font color=\"#ff0000\" size=\"3\"><\/font><font size=\"2\"><em><\/em><\/font><\/p>\n<p>**<font color=\"#ff0000\" size=\"3\"><\/font><font size=\"2\"><em>STS-124 Sub Section Build-Up \u2013 special section Now Live. Now includes over 100mb of Flight Plans, EVA, RNDZ, Ascent etc. Checklists. Mission Overview&nbsp;CGI Videos.&nbsp;Plus 14 Flight Readiness Review (FRR) Presentations.<\/em><\/font><\/p>\n<p>**STS-125\/LON-400 Sub Section Special already over 1300mb in size \u2013 special section Now Live.<\/p>\n<p><font size=\"3\">&nbsp;<br \/><em><font color=\"#0000ff\" size=\"2\">**LIVE updates: Endeavour&nbsp;Dual LON and STS-126 Processing**<\/font><\/em><\/font><\/p>\n<p><font color=\"#0000ff\" size=\"2\"><em>**LIVE updates on Atlantis&nbsp;STS-125 Processing Flow**<\/em><\/font><\/p>\n<p><font color=\"#0000ff\" size=\"2\"><em>**LIVE updates on Discovery STS-124 Processing (PAD FLOW)**<\/em><\/font><br \/>&nbsp;<\/p>\n<p>NASA mission patches<path d=\"M7.59009 18.59L9.00009 20L17.0001 12L9.00009 4L7.59009 5.41L14.1701 12\" style=\"animation: initial !important; background: initial !important; border: 0px !important; box-shadow: none !important; color: inherit !important; cursor: inherit !important; direction: inherit !important; display: inline !important; fill: currentcolor !important; filter: initial !important; float: none !important; margin: 0px !important; opacity: initial !important; outline: 0px !important; overflow: initial !important; padding: 0px !important; stroke: initial !important; transform: initial !important; vertical-align: initial !important; visibility: inherit !important;\"><\/path>Space Shuttle models<path d=\"M7.59009 18.59L9.00009 20L17.0001 12L9.00009 4L7.59009 5.41L14.1701 12\" style=\"animation: initial !important; background: initial !important; border: 0px !important; box-shadow: none !important; color: inherit !important; cursor: inherit !important; direction: inherit !important; display: inline !important; fill: currentcolor !important; filter: initial !important; float: none !important; margin: 0px !important; opacity: initial !important; outline: 0px !important; overflow: initial !important; padding: 0px !important; stroke: initial !important; transform: initial !important; vertical-align: initial !important; visibility: inherit !important;\"><\/path>SpaceX launch tickets<path d=\"M7.59009 18.59L9.00009 20L17.0001 12L9.00009 4L7.59009 5.41L14.1701 12\" style=\"animation: initial !important; background: initial !important; border: 0px !important; box-shadow: none !important; color: inherit !important; cursor: inherit !important; direction: inherit !important; display: inline !important; fill: currentcolor !important; filter: initial !important; float: none !important; margin: 0px !important; opacity: initial !important; outline: 0px !important; overflow: initial !important; padding: 0px !important; stroke: initial !important; transform: initial !important; vertical-align: initial !important; visibility: inherit !important;\"><\/path>\n<p>     (adsbygoogle = window.adsbygoogle || []).push({});<\/p>\n<p><u><em>STS-124:<\/em><\/u> <\/p>\n<p><img loading=\"lazy\" decoding=\"async\" height=\"125\" alt=\"\" hspace=\"5\" src=\"http:\/\/forum.nasaspaceflight.com\/forums\/get-attachment.asp?action=view&amp;attachmentid=47804\" width=\"125\" align=\"left\" vspace=\"5\" border=\"0\/\">Pad processing is continuing on schedule, with the next major milestone relating to orbiter aft closeouts, which begin on Friday 2nd shift. The only new issue noted on Thursday processing reports relates to power supplies, which is undergoing an engineering evaluation. <\/p>\n<p>\u2018The 1D100 and 1D500 power supplies failed to return to zero volts indication following vehicle power down,\u2019 noted the latest processing report. \u2018The constraint right now is paper only. Awaiting engineering evaluation.\u2019 <\/p>\n<p>With the SSP (Space Shuttle Program) FRR concluding this week, the launch date will be set by the upcoming Agency FRR \u2013 set to meet on Monday. <\/p>\n<p>The two issues relating to Soyuz\u2019s ability as a \u2018solid rescue vehicle\u2019 at the&nbsp;International Space Station (ISS),&nbsp;and the on-time delivery requirement of the CO2 scrubber have previously been&nbsp;reported. Below is an expansion on the other two items of interest.<\/p>\n<p><b><i><u>Discovery\u2019s GPC Update:<\/u><\/i><\/b> <\/p>\n<p>A subject of FRR interest is the other issue noted during the pad flow, specifically the cause of an off-nominal 2-1-1 spilt of the GPCs \u2013 believed to have been caused by a faulty MDM (Multiplexer\/Demultiplexer) card (FA2).<\/p>\n<p>Following approval by Wednesday\u2019s Noon PRCB (Program Requirements Control Board) to carry out the removal and replacement of the faulty hardware from Discovery\u2019s aft, engineers completed the removal task overnight.<\/p>\n<p>Re-testing will take place over the next 24-48 hours, though an item of interest was found during the removal of the faulty MDM \u2013 which was subsequently replaced on Thursday afternoon. <\/p>\n<p>\u2018The go to R&amp;R MDM FA2 was given yesterday afternoon and the R&amp;R was worked overnight,\u2019 confirmed Thursday processing information. \u2018After MDM removal, a scratch was found on the cold plate. Mold impressions were made and are under evaluation.\u2019<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" height=\"183\" alt=\"\" hspace=\"5\" src=\"http:\/\/forum.nasaspaceflight.com\/forums\/get-attachment.asp?action=view&amp;attachmentid=45691\" width=\"232\" align=\"left\" vspace=\"5\" border=\"0\/\"><em><font color=\"#0033ff\">Now on L2: A stunning 50 minute (1.9gb) high quality camcorder video of a special All Access tour of the VAB, Pad and OPF-3. Get up close with two orbiters, next to the engineers, ride the VAB elevator to the top of the building, walk around the pad and enter OPF-3 to within touching distance of Atlantis. <font color=\"#ff0000\">FREE TRAILER NOW AVAILABLE \u2013 CLICK IMAGE<\/font>.<\/font><\/em><\/p>\n<p>The cold plates \u2013 which transport the heat away from the electronics boxes \u2013 have had scratches observed in previous flows. However, despite the ability of scratches to change the heat transfer characteristics, the scratch observed is understood to be too small to have any relation to the MDM failure.<\/p>\n<p>\u2018S0024, pre-launch propellant servicing, will pick up with fuel loading operations after the portion of the retest to support S0024 operations is complete,\u2019 added processing information. \u2018Further MDM retesting requirements will continue through Saturday including Orbiter and SRB hydraulic operations.\u2019<\/p>\n<p>While the re-test is almost certain to correct the issue with the GPCs, the root cause is the main focus of attention that Monday\u2019s FRR will be tasked with debating. <\/p>\n<p>Engineers are certain the now-replaced MDM caused the problem, backed up by the findings from the retests performed overnight. However, what caused the MDM to fail \u2013 and the subsequent issues with the GPCs, remains unknown. <\/p>\n<p>The fault tree shows that the GPCs \u2013 which read data and send commands to the MDMs \u2013 first encountered the problem when GPC 4 received erroneous (non-universal I\/O Errors) data, which did not match the other GPCs in the redundant set. As programmed, GPC 4 was voted out. <\/p>\n<p>Three seconds later, the same thing happened with GPC 2. At that time GPCs 2 and 4 were powered down and an MDM FA2 BITE Status Register (BSR) read was performed on MDM FA2 port 1, causing GPC 3 to fail out of set with GPC 1. This is known as a \u20182-1-1 Split\u2019. <\/p>\n<p>At that point, GPC1 was operated in simplex mode to obtain more data. Engineers terminated the work in process and powered down the vehicle for the changeout of the suspect MDM. <\/p>\n<p>When re-testing is completed at the weekend, the engineers will present their full overview to the FRR, who will ultimately decide if they are happy to proceed with the May 31st launch \u2013 even without root cause. This is deemed likely, given the MDM is classed as the problem, which has since been removed from the fault tree. <\/p>\n<p><em><u>Elbow Camera Clearances:<\/u><\/em> <\/p>\n<p>This issue is more related to double checking the clearances of the elbow camera on the end of the SRMS (Shuttle Remote Manipulator System) arm and the giant Japanese payload. <\/p>\n<p>\u201cGot some pictures of elbow camera installation and the strap. KSC GO was also in the process of taking measurements for us,\u201d noted the Orbiter Project. \u201cBased on the initial picture, we were concerned that the camera might be in a little different than the 0 degrees position, so had a telecon.\u201d <\/p>\n<p>\u201cAsked the Cape to take an additional measurement. Based on this additional measurement and photo analysis, we determined that the camera is 5 or 5.5 degrees off of the 0 based on the pictures, or based on the one measurement \u2013 3 degrees off. <\/p>\n<p>\u201cAll of these are within the allowable 6 degrees it could be in and still maintain positive clearance. Some of the guys are looking at the strap, but based on where the camera is, Orbiter does not have a problem with clearance for ascent.\u201d <\/p>\n<p>The camera has a strap and a wedge to hold it in place \u2013 and away from contacting the JAXA Pressurized Module (JEM) \u2013 during the ride uphill. There isn\u2019t a plan to reopen the Payload Bay doors, unless the FRR requests it.<\/p>\n<p>\u201cOn the elbow camera, need to remember this is the tightest clearance for any cameras for any of the flights we\u2019ve ever flown. Had to build a special GFE (General Flight Equipment) wedge to move the camera away from the JEM. <\/p>\n<p>\u201cWant to understand the strap configuration, and make sure that has not changed the dynamics of the situation. Will get the team together to make sure have a good story going forward to the FRR. <\/p>\n<p>\u201cThere is no plan to open the doors, but we have worked with KSC and there is an opportunity we need to get in there and reposition that camera.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Discovery\u2019s STS-124 mission remains on track, pending the satisfactory outcome of four issues \u2013 all of which are heading to the agency Flight Readiness Review (FRR) next Monday. A successful re-test of Discovery\u2019s General Purpose Computers (GPCs), final confirmation that elbow camera clearances are within spec, a satisfactory status update of the Russian Soyuz investigation, [&hellip;]<\/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":[],"class_list":["post-41415","post","type-post","status-publish","format-standard","hentry","category-news"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/41415"}],"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=41415"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/41415\/revisions"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=41415"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=41415"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=41415"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}