{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T11:56:25Z","timestamp":1785412585923,"version":"3.56.0"},"reference-count":39,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T00:00:00Z","timestamp":1780358400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["U2433213"],"award-info":[{"award-number":["U2433213"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["U2433213"],"award-info":[{"award-number":["U2433213"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper aims to develop an on-board shock absorber detection method for general aviation aircraft. The effects of common gas and oleo leakage are analyzed in this paper. Based on the principle of landing gear dynamics, it is found that gas leakage and oleo leakage would mainly affect air spring force of shock absorbers in various ways. A rigid\u2013flexible coupled landing gear multi-body system (MBS) model is developed by considering strut flexibility, aiming to offer more accurate simulated responses. A database is developed that considers common leakage faults and typical landing conditions using the developed landing gear model. A deep learning model is proposed in this paper. The proposed model is trained and tested using the database simulated from the rigid\u2013flexible coupling landing gear model. The proposed method demonstrates robust detection performance, achieving over 95% precision for most fault types. This work provides a practical, sensor-efficient solution for real-time health monitoring of landing gear shock absorbers, contributing to improved maintenance strategies and operational safety for general aviation aircraft. As this is a preliminary feasibility study, full validation requires future drop tests or instrumented flight tests.<\/jats:p>","DOI":"10.3390\/s26113509","type":"journal-article","created":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T11:25:31Z","timestamp":1780399531000},"page":"3509","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["An On-Board Shock Absorber Detection Method for General Aviation Aircraft Landing Gears"],"prefix":"10.3390","volume":"26","author":[{"given":"Chunsheng","family":"Li","sequence":"first","affiliation":[{"name":"Department of Aircraft Engineering, College of Aviation Engineering, Civil Aviation Flight University of China, Chengdu 641419, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haoyu","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Aircraft Engineering, College of Aviation Engineering, Civil Aviation Flight University of China, Chengdu 641419, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zongguang","family":"Shen","sequence":"additional","affiliation":[{"name":"Department of Aircraft Engineering, College of Aviation Engineering, Civil Aviation Flight University of China, Chengdu 641419, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,2]]},"reference":[{"key":"ref_1","first-page":"107","article-title":"Fault prediction for airplane shock absorber based on LVQ neural network","volume":"39","author":"Wu","year":"2014","journal-title":"Lubr. 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