{"id":45216,"date":"2024-05-07T22:18:54","date_gmt":"2024-05-07T14:18:54","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/faulty-valve-scuttles-starliners-first-crew-launch\/"},"modified":"2024-05-07T22:18:54","modified_gmt":"2024-05-07T14:18:54","slug":"faulty-valve-scuttles-starliners-first-crew-launch","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/faulty-valve-scuttles-starliners-first-crew-launch\/","title":{"rendered":"Faulty valve scuttles Starliner\u2019s first crew launch"},"content":{"rendered":"

Astronauts Butch Wilmore and Suni Williams climbed into their seats inside Boeing\u2019s Starliner spacecraft Monday night in Florida, but trouble with the capsule\u2019s Atlas V rocket kept the commercial ship\u2019s long-delayed crew test flight on the ground.<\/p>\n

Around two hours before launch time, shortly after 8:30 pm EDT (00:30 UTC), United Launch Alliance\u2019s launch team stopped the countdown. \u201cThe engineering team has evaluated, the vehicle is not in a configuration where we can proceed with flight today,\u201d said Doug Lebo, ULA\u2019s launch conductor.<\/p>\n

The culprit was a misbehaving valve on the rocket\u2019s Centaur upper stage, which has two RL10 engines fed by supercold liquid hydrogen and liquid oxygen propellants.<\/p>\n

\u201cWe saw a self-regulating valve on the LOX (liquid oxygen) side had a bit of a buzz; it was moving in a strange behavior,\u201d said Steve Stich, NASA\u2019s commercial crew program manager. \u201cThe flight rules had been laid out for this flight ahead of time. With the crew at the launch pad, the proper action was to scrub.\u201d<\/p>\n

The next opportunity to launch Starliner on its first crew test flight will be May 17 at 6:16 pm EDT (22:16 UTC), NASA announced late Tuesday. Managers spent Tuesday reviewing data from the faulty valve and determined it should be replaced. This will require ULA to roll the Atlas V rocket back into its hangar about a third-of-a-mile south of the launch pad, eliminating any chance to launch the mission later this week.<\/p>\n

Work ahead<\/h2>\n

Everything else was going smoothly in the countdown Monday night as Wilmore and Williams strapped into their seats for the first crew flight on the Starliner spacecraft and Atlas V rocket from Cape Canaveral Space Force Station, Florida. This flight is the culmination of nearly a decade-and-a-half of development by Boeing, which has a $4.2 billion contract with NASA to ready Starliner for crew missions, then carry out six long-duration crew ferry flights to and from the International Space Station.<\/p>\n

,<\/p>\n

The crew test flight will last at least eight days, taking Wilmore and Williams to the space station to verify Starliner\u2019s readiness for operational missions. Once Starliner flies, NASA will have two human-rated spacecraft on contract. SpaceX\u2019s Crew Dragon has been in service since 2020.<\/p>\n

After officials called off the launch attempt, the Boeing and ULA support team helped the astronauts out of the capsule and drove them back to crew quarters at the nearby Kennedy Space Center to wait for the next launch attempt.<\/p>\n

\u201cI promised Butch and Suni a boring evening,\u201d said Tory Bruno, ULA\u2019s CEO. \u201cI didn\u2019t mean for it to be quite this boring, but we\u2019re going to follow our rules, and we\u2019re going to make sure that the crew is safe.\u201d<\/p>\n

The valve in question vents gas from the liquid oxygen tank on the Centaur upper stage to maintain the tank at proper pressures. This is important for two reasons. The tank needs to be at the correct pressure for the RL10 engines to receive propellant during the flight, and the Centaur upper stage itself has ultra-thin walls to reduce weight, and requires pressure to maintain structural integrity.<\/p>\n

\n

\"\"<\/p>\n

Astronauts Suni Williams and Butch Wilmore, wearing their Boeing spacesuits, during Monday evening\u2019s launch attempt.<\/p>\n

Credit:
\n NASA\/Kim Shiflett<\/p>\n<\/figure>\n

Around an hour before ULA scrubbed the launch attempt, the launch team noticed oscillations in measurements at the top of the Centaur liquid oxygen tank. The ground crew at the launch pad, a few feet from the rocket, reported an unusual \u201cchattering\u201d sound at the same time.<\/p>\n

This chattering or buzzing sound was associated with rapid movement of the relief valve. In this case, it was cycling about 40 times per second.<\/p>\n

\u201cEvery now and again, on rare occasions, a valve like that can get into a position where it\u2019s just off the seat,\u201d Bruno said. \u201cIts temperature, its stiffness, everything is just right and it will flutter, or it\u2019ll buzz in this base. It will cycle. We\u2019ve seen that before.\u201d<\/p>\n

,<\/p>\n

On previous occasions, such as on an Atlas V launch in 2015, ULA\u2019s launch team commanded the valve closed and reopened the valve, and the buzzing motion stopped. This allowed the launch to proceed successfully. For safety reasons, ULA didn\u2019t want to take that step with the astronauts inside the Starliner spacecraft atop the rocket, so they waited until the crew departed the launch pad Monday night.<\/p>\n

\u201cIf this was a satellite, that is our standard procedures, and the satellite would already be in orbit,\u201d Bruno said in a press conference Monday night. \u201cBut that changes the state of the fueled Centaur, and we don\u2019t do that when people are present. So our flight rules called for us to scrub and take the crew off before we cycled that valve.\u201d<\/p>\n

Once the astronauts were safely away from the rocket, ULA\u2019s launch team temporarily dampened the valve oscillations, but then the rapid movement resumed twice as engineers drained propellants from the Atlas V. Bruno said the valve is capable of functioning normally after at least 200,000 cycles, and the valve exceeded that limit.<\/p>\n

\u201cAfter evaluating the valve history, data signatures from the launch attempt, and assessing the risks relative to continued use, the ULA team determined the valve exceeded its qualification and mission managers agreed to remove and replace the valve,\u201d NASA said in a statement Tuesday night.<\/p>\n

Teams will roll the Atlas V and Starliner back to ULA\u2019s vertical hangar on Wednesday. There, technicians would change out the valve, a process that Bruno said would take a few days. \u201cThe ULA team will perform leak checks and functional checkouts in support of the next launch attempt,\u201d NASA said.<\/p>\n

This story was updated at 8:15 pm ET after NASA announced an additional delay until May 17.<\/i><\/p>\n","protected":false},"excerpt":{"rendered":"

Astronauts Butch Wilmore and Suni Williams climbed into their seats inside Boeing\u2019s Starliner spacecraft Monday night in Florida, but trouble with the capsule\u2019s Atlas V rocket kept the commercial ship\u2019s long-delayed crew test flight on the ground. Around two hours before launch time, shortly after 8:30 pm EDT (00:30 UTC), United Launch Alliance\u2019s launch team stopped […]<\/p>\n","protected":false},"author":1,"featured_media":45217,"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":[7758,670,1163,524,1545,717,190,1306,1166,750],"class_list":["post-45216","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news","tag-atlas-v","tag-boeing","tag-butch-wilmore","tag-commercial-crew","tag-human-spaceflight","tag-international-space-station","tag-nasa","tag-starliner","tag-suni-williams","tag-united-launch-alliance"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/45216"}],"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=45216"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/45216\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media\/45217"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=45216"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=45216"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=45216"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}