{"id":10104,"date":"2024-05-24T22:21:52","date_gmt":"2024-05-24T14:21:52","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/nasa-says-boeings-starliner-crew-capsule-can-safely-fly-as-is-with-propulsion-system-helium-leak\/"},"modified":"2024-05-24T22:21:52","modified_gmt":"2024-05-24T14:21:52","slug":"nasa-says-boeings-starliner-crew-capsule-can-safely-fly-as-is-with-propulsion-system-helium-leak","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/nasa-says-boeings-starliner-crew-capsule-can-safely-fly-as-is-with-propulsion-system-helium-leak\/","title":{"rendered":"NASA says Boeing\u2019s Starliner crew capsule can safely fly \u2018as is\u2019 with propulsion system helium leak"},"content":{"rendered":"<figure id=\"attachment_66297\" aria-describedby=\"caption-attachment-66297\" style=\"width: 678px\" class=\"wp-caption aligncenter\"><img fetchpriority=\"high\" decoding=\"async\" src=\"http:\/\/spaceflightnow.com\/wp-content\/uploads\/2024\/05\/20240524-Starliner-Feature-Image.jpg\" alt=\"\" width=\"678\" height=\"381\" class=\"size-full wp-image-66297\" srcset=\"https:\/\/spaceflightnow.com\/wp-content\/uploads\/2024\/05\/20240524-Starliner-Feature-Image.jpg 678w, https:\/\/spaceflightnow.com\/wp-content\/uploads\/2024\/05\/20240524-Starliner-Feature-Image-300x169.jpg 300w\" sizes=\"(max-width: 678px) 100vw, 678px\"><figcaption id=\"caption-attachment-66297\" class=\"wp-caption-text\">Boeing\u2019s Starliner capsule atop the Atlas 5 rocket inside United Launch Alliance\u2019s Vertical Integration Facility (VIF) at Space Launch Complex 41 at Cape Canaveral. Image: United Launch Alliance.<\/figcaption><\/figure>\n<p>After nearly three weeks of exhaustive tests and data analysis, NASA managers said Friday they are confident Boeing\u2019s oft-delayed Starliner crew capsule can safely launch \u201cas is\u201d June 1, saying a small helium leak in the ship\u2019s propulsion system does not pose a flight safety concern.<\/p>\n<p>Steve Stich, manager of NASA\u2019s Commercial Crew Program, said even if a suspect shirt-button-size rubber seal in the plumbing leading to one specific thruster failed completely in flight \u2014 resulting in a leak rate 100 times worse than what\u2019s been observed to date \u2014 the Starliner could still fly safely.<\/p>\n<p>\u201cShould we be wrong about something, we could handle up to four more leaks,\u201d he said. \u201cAnd we could handle this particular leak if that leak rate were to grow, even up to 100 times in this one (propulsion module).\u201d<\/p>\n<p>What will now be a nearly one-month-long launch delay was required because \u201cwe needed to take the time to work through this analysis, and to understand the helium leak and understand the ramifications of that,\u201d Stich said.<\/p>\n<p>And to give the work force time off over the Memorial Day holiday weekend.<\/p>\n<p>The Starliner\u2019s two NASA crew members, commander Barry \u201cButch\u201d Wilmore and co-pilot Sunita Williams, plan to fly back to the Kennedy Space Center next Tuesday to prepare for launch from the Cape Canaveral Space Force Station atop an Atlas 5 rocket at 12:25 p.m. EDT June 1.<\/p>\n<p>If all goes well, they will dock at the International Space Station the next day and return to Earth on June 10.<\/p>\n<p><iframe loading=\"lazy\" title=\"YouTube video player\" src=\"https:\/\/www.youtube.com\/embed\/j_cloqobD0I\" width=\"678\" height=\"381\" frameborder=\"0\" allowfullscreen=\"allowfullscreen\"><\/iframe><\/p>\n<p>Wilmore and Williams were in the process of strapping in for launch May 6 when the countdown was aborted because of problems with an oxygen pressure relief valve in their Atlas 5\u2019s Centaur upper stage. Rocket-builder United Launch Alliance hauled the booster back to a processing facility and replaced the valve without incident.<\/p>\n<p>At the same time, Boeing engineers began a detailed investigation of a small helium leak in one of the Starliner\u2019s four propulsion modules, known as \u201cdoghouses,\u201d that showed up when valves were closed as part of normal post-scrub procedures.<\/p>\n<p>The leak eventually was traced to a flange where propellant lines feeding a specific reaction control system thruster in the port doghouse come together. The Starliner is equipped with 28 RCS jets, and helium is used to pressurize the propellant lines, opening and closing valves in each doghouse as needed.<\/p>\n<p>Because traces of extremely toxic propellants could still be present in the plumbing, the seal could not be replaced or even inspected while the capsule was still attached to the Atlas 5. The Starliner would first have to be hauled back to Boeing\u2019s processing hangar at the Kennedy Space Center for invasive repairs that would trigger a lengthy delay.<\/p>\n<p>Instead, NASA and Boeing ordered tests and analysis to fully understand the leak and what sort of problems it might cause in flight. The observed leak rate did not appear to be a concern, but engineers needed to gain confidence it would not dramatically worsen. They also wanted to make sure no other systems were affected.<\/p>\n<p>Stich said the seal in question likely was crimped or had a tiny defect, allowing helium to slip through. But testing showed that even if the seal was removed from the flange, the Starliner could still fly safely. The helium manifold in question could be isolated and the Starliner\u2019s many other thrusters could easily compensate.<\/p>\n<p><iframe loading=\"lazy\" title=\"YouTube video player\" src=\"https:\/\/www.youtube.com\/embed\/TzVEdln_L8E\" width=\"678\" height=\"381\" frameborder=\"0\" allowfullscreen=\"allowfullscreen\"><\/iframe><\/p>\n<p>Mark Nappi, Boeing\u2019s Starliner program manager, said the May 6 launch scrub had a \u201csilver lining,\u201d because it brought the helium leak to everyone\u2019s attention and \u201cwe now know exactly where it was, we have done all the work to understand the root cause and that\u2019s going to help us with improving the system in the future.\u201d<\/p>\n<p>\u201cHad we launched \u2026 it would have been a safe flight and a successful flight,\u201d he said, \u201cbut we would have not known as much as we know today.\u201d<\/p>\n<p>That includes one unexpected result, what Stich called \u201ca design vulnerability.\u201d The investigation shows that in the very remote chance of major trouble with two adjacent doghouses, including the one with the helium leak, the Starliner could lose redundancy for the thruster firing needed to drop out of orbit for re-entry.<\/p>\n<p>The Starliner was designed to support three redundant de-orbit capabilities. In one, the braking burn is carried out with four powerful orbital maneuvering and attitude control \u2014 OMAC \u2014 thrusters. The burn also can be carried out with just two working OMAC jets, or with eight smaller RCS thrusters by firing them longer than planned.<\/p>\n<p>In the right circumstances, with adjacent doghouse modules out of action, the Starliner could lose the full eight-thruster RCS deorbit capability.<\/p>\n<p>\u201cWe\u2019ve worked with the vendor of the thruster, Boeing and our NASA team to come up with a redundant method to do the orbit burn, to break it up into two burns about 10 minutes each, 80 minutes apart, to come up with a four-RCS-thruster deorbit burn and to regain the capability of the original system,\u201d Stich said.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Boeing\u2019s Starliner capsule atop the Atlas 5 rocket inside United Launch Alliance\u2019s Vertical Integration Facility (VIF) at Space Launch Complex 41 at Cape Canaveral. Image: United Launch Alliance. After nearly three weeks of exhaustive tests and data analysis, NASA managers said Friday they are confident Boeing\u2019s oft-delayed Starliner crew capsule can safely launch \u201cas is\u201d [&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":[1379,822],"class_list":["post-10104","post","type-post","status-publish","format-standard","hentry","category-news","tag-cft","tag-cst-100-starliner-crew-flight-test"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/10104"}],"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=10104"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/10104\/revisions"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=10104"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=10104"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=10104"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}