Thin-Flexible Broad-Band Resistive Frequency Selective Surface Radar Absorbing Material for Low Observable Aircraft Air Intake Application

Thin-Flexible Broad-Band Resistive Frequency Selective Surface Radar Absorbing Material for Low Observable Aircraft Air Intake Application | 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 Thin-Flexible Broad-Band Resistive Frequency Selective Surface Radar Absorbing Material for Low Observable Aircraft Air Intake Application Vijay Kumar Sutrakar, Preeti Kumari, Himanshu B Baskey This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8289189/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract An aircraft consists of various cavities including air intake ducts, cockpit, radome, inlet and exhaust of heat exchangers, passage for engine bay/other bay for cooling of aircraft systems etc. These cavities are the prime contributors for aircraft radar cross-section (RCS). These cavities are of different cross-sectional areas as well as different lengths depending on the applications on aircraft. The RCS reductions of these cavities are very important to achieve a low observable aircraft configuration. In this paper, a thin-flexible resistive frequency selective surface (FSS) based radar absorbing material (RAM) design is presented. The proposed FSS-RAM is of 0.15mm thickness. Computational result shows > 10dB RCS reduction from 12.5GHz to 40GHz on a flat radar absorbing structure (RAS) panel of 2.0mm thickness with metal backing. The results are further validated with experiments from 8 to 18GHz of frequencies. This FSS based RAS is then computationally implemented on different circular cavities with varying L/D ratios and its performance are compared with the conventional non-RAS cavities. Significant RCS reduction demonstrates possible application of FSS based RAS on various cavities of futuristic aircraft platform for achieving very low observability. Lastly, the performance of the FSS-RAM based RAS of thickness 2.0mm is also demonstrated on an open-source CAD model of conventional fighter aircraft. Aircraft frontal sector of 0 0 to 15 0 shows ~ 7.75Db median RCS reduction and 0 0 to 60 0 shows ~ 8.72dB median RCS reduction from 8GHz to 18GHz frequencies using the proposed FSS RAM based RAS of 2.0mm thickness. Aeronautics and Astronautics Materials Engineering Computational Physics radar absorbing material (RAM) radar cross-section (RCS) frequency selective surface (FSS) radar absorbing structure (RAS) cavities stealth aircraft Full Text Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-8289189","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":555905631,"identity":"883c1c86-e1aa-419b-8a19-dc6c45b07e4f","order_by":0,"name":"Vijay Kumar 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Aircraft Air Intake Application\u003c/strong\u003e\u003c/p\u003e","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"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":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"radar absorbing material (RAM), radar cross-section (RCS), frequency selective surface (FSS), radar absorbing structure (RAS), cavities, stealth aircraft","lastPublishedDoi":"10.21203/rs.3.rs-8289189/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8289189/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eAn aircraft consists of various cavities including air intake ducts, cockpit, radome, inlet and exhaust of heat exchangers, passage for engine bay/other bay for cooling of aircraft systems etc. These cavities are the prime contributors for aircraft radar cross-section (RCS). These cavities are of different cross-sectional areas as well as different lengths depending on the applications on aircraft. The RCS reductions of these cavities are very important to achieve a low observable aircraft configuration. In this paper, a thin-flexible resistive frequency selective surface (FSS) based radar absorbing material (RAM) design is presented. The proposed FSS-RAM is of 0.15mm thickness. Computational result shows\u0026thinsp;\u0026gt;\u0026thinsp;10dB RCS reduction from 12.5GHz to 40GHz on a flat radar absorbing structure (RAS) panel of 2.0mm thickness with metal backing. The results are further validated with experiments from 8 to 18GHz of frequencies. This FSS based RAS is then computationally implemented on different circular cavities with varying L/D ratios and its performance are compared with the conventional non-RAS cavities. Significant RCS reduction demonstrates possible application of FSS based RAS on various cavities of futuristic aircraft platform for achieving very low observability. Lastly, the performance of the FSS-RAM based RAS of thickness 2.0mm is also demonstrated on an open-source CAD model of conventional fighter aircraft. Aircraft frontal sector of 0\u003csup\u003e0\u003c/sup\u003e to 15\u003csup\u003e0\u003c/sup\u003e shows\u0026thinsp;~\u0026thinsp;7.75Db median RCS reduction and 0\u003csup\u003e0\u003c/sup\u003e to 60\u003csup\u003e0\u003c/sup\u003e shows\u0026thinsp;~\u0026thinsp;8.72dB median RCS reduction from 8GHz to 18GHz frequencies using the proposed FSS RAM based RAS of 2.0mm thickness.\u003c/p\u003e","manuscriptTitle":"Thin-Flexible Broad-Band Resistive Frequency Selective Surface Radar Absorbing Material for Low Observable Aircraft Air Intake Application","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-12-08 07:40:38","doi":"10.21203/rs.3.rs-8289189/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"6579a32e-a585-458a-800a-05454488fefc","owner":[],"postedDate":"December 8th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":59168962,"name":"Aeronautics and Astronautics"},{"id":59168963,"name":"Materials Engineering"},{"id":59168964,"name":"Computational Physics"}],"tags":[],"updatedAt":"2025-12-08T07:40:38+00:00","versionOfRecord":[],"versionCreatedAt":"2025-12-08 07:40:38","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8289189","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8289189","identity":"rs-8289189","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}