Unsteady Loads on a Descending Launcher First Stage Demonstrator in the Aerodynamic Phase

Unsteady Loads on a Descending Launcher First Stage Demonstrator in the Aerodynamic Phase | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Unsteady Loads on a Descending Launcher First Stage Demonstrator in the Aerodynamic Phase Ansgar Marwege, Junnai Zhai, Ali Guelhan This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8914694/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 9 You are reading this latest preprint version Abstract In the Horizon Europe Project SALTO, a demonstrator of a vertically landing first stage with three Prometheus engines, the so-called T3, was investigated. It is intended to be recovered using a downrange landing approach. In this paper, the aerodynamic phase of the descent trajectory was investigated through wind tunnel experiments of the full launcher configuration in the Trisonic Wind Tunnel Cologne (TMK). The unsteady pressure fluctuations measured with high-frequency pressure sensors are presented. Especially on the base area of the vehicle, high pressure fluctuations were measured, with values around 30% of the dynamic pressure and occasionally up to 40%. The pressure fluctuations around the grid fins were lower but still on the order of 10%. The measured fluctuations did not exhibit prominent frequencies and were mainly broadband in nature. SALTO Unsteady Loads Aerodynamic Phase Wind Tunnel Experiments Vertical Landing Launcher Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 30 Apr, 2026 Reviews received at journal 29 Apr, 2026 Reviews received at journal 20 Apr, 2026 Reviewers agreed at journal 17 Mar, 2026 Reviewers agreed at journal 26 Feb, 2026 Reviewers invited by journal 25 Feb, 2026 Editor assigned by journal 22 Feb, 2026 Submission checks completed at journal 19 Feb, 2026 First submitted to journal 19 Feb, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8914694","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":597555966,"identity":"7d88a9ab-3896-4889-ae6e-2a90aa51c311","order_by":0,"name":"Ansgar Marwege","email":"","orcid":"","institution":"German Aerospace Center","correspondingAuthor":false,"prefix":"","firstName":"Ansgar","middleName":"","lastName":"Marwege","suffix":""},{"id":597555969,"identity":"43ac6b86-5017-4f55-baa6-87ca4dc131ee","order_by":1,"name":"Junnai Zhai","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA2ElEQVRIie3OMQrCMBTG8VeEdgkFt4aKZ/hcKoKHSScXFcHFTUXI5AEcepiCYJeCqyJou2dwdHAwVXFsOjrkP4QE8uM9IpvtD/NW1Qlagpx1wWb6kRqI8yUtTTZgaEyoIuQGzchucigeM3L73l4uFK7kZysTmY56WxAbbGN5TjAnnhvGOLtxVO0TII3lhUEQTsJM+BMEHEs5f5NbUU/amoR6isAplq3PlHpBIVNR2EGgSbnhCQTjuWEx39OLqedwieOovKuF6PpZahjzKfjdWKP/NpvNZqvvBTrcPxcKATXlAAAAAElFTkSuQmCC","orcid":"","institution":"German Aerospace Center","correspondingAuthor":true,"prefix":"","firstName":"Junnai","middleName":"","lastName":"Zhai","suffix":""},{"id":597555972,"identity":"68d401b5-167c-4422-946b-12970bbe6664","order_by":2,"name":"Ali Guelhan","email":"","orcid":"","institution":"German Aerospace Center","correspondingAuthor":false,"prefix":"","firstName":"Ali","middleName":"","lastName":"Guelhan","suffix":""}],"badges":[],"createdAt":"2026-02-19 06:53:39","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8914694/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8914694/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[],"financialInterests":"No competing interests reported.","formattedTitle":"Unsteady Loads on a Descending Launcher First Stage Demonstrator in the Aerodynamic Phase","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"ceas-space-journal","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ceas","sideBox":"Learn more about [CEAS Space Journal](http://link.springer.com/journal/12567)","snPcode":"12567","submissionUrl":"https://submission.nature.com/new-submission/12567/3","title":"CEAS Space Journal","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"SALTO, Unsteady Loads, Aerodynamic Phase, Wind Tunnel Experiments, Vertical Landing, Launcher","lastPublishedDoi":"10.21203/rs.3.rs-8914694/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8914694/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eIn the Horizon Europe Project SALTO, a demonstrator of a vertically landing first stage with three Prometheus engines, the so-called T3, was investigated. 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