{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T00:44:44Z","timestamp":1760402684216,"version":"build-2065373602"},"reference-count":41,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2020,4,29]],"date-time":"2020-04-29T00:00:00Z","timestamp":1588118400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Defence Agency","award":["ASTYANAX"],"award-info":[{"award-number":["ASTYANAX"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Maximum loads acting on aircraft structures generally arise when the aircraft is undergoing some form of acceleration, such as during landing. Landing, especially when considering rotorcrafts, is thus crucial in determining the operational load spectrum, and accurate predictions on the actual health\/load level of the rotorcraft structure cannot be achieved unless a database comprising the structural response in various landing conditions is available. An effective means to create a structural response database relies on the modeling and simulation of the items and phenomena of concern. The structural response to rotorcraft landing is an underrated topic in the open scientific literature, and tools for the landing event simulation are lacking. In the present work, a coupled sequential simulation strategy is proposed and experimentally verified. This approach divides the complex landing problem into two separate domains, namely a dynamic domain, which is ruled by a multibody model, and a structural domain, which relies on a finite element model (FEM). The dynamic analysis is performed first, calculating a set of intermediate parameters that are provided as input to the subsequent structural analysis. Two approaches are compared, using displacements and forces at specific airframe locations, respectively, as the link between the dynamic and structural domains.<\/jats:p>","DOI":"10.3390\/s20092540","type":"journal-article","created":{"date-parts":[[2020,4,29]],"date-time":"2020-04-29T13:23:45Z","timestamp":1588166625000},"page":"2540","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["On the Evaluation of a Coupled Sequential Approach for Rotorcraft Landing Simulation"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9054-0366","authenticated-orcid":false,"given":"Demetrio","family":"Cristiani","sequence":"first","affiliation":[{"name":"Dipartimento di Meccanica, Politecnico di Milano, 20156 Milano, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9355-099X","authenticated-orcid":false,"given":"Luca","family":"Colombo","sequence":"additional","affiliation":[{"name":"Dipartimento di Meccanica, Politecnico di Milano, 20156 Milano, Italy"}]},{"given":"Wojciech","family":"Zielinski","sequence":"additional","affiliation":[{"name":"Air Force Institute of Technology, Airworth, Division, 01-494 Warsaw, Poland"}]},{"given":"Claudio","family":"Sbarufatti","sequence":"additional","affiliation":[{"name":"Dipartimento di Meccanica, Politecnico di Milano, 20156 Milano, Italy"}]},{"given":"Francesco","family":"Cadini","sequence":"additional","affiliation":[{"name":"Dipartimento di Meccanica, Politecnico di Milano, 20156 Milano, Italy"}]},{"given":"Michal","family":"Dziendzikowski","sequence":"additional","affiliation":[{"name":"Air Force Institute of Technology, Airworth, Division, 01-494 Warsaw, Poland"}]},{"given":"Marco","family":"Giglio","sequence":"additional","affiliation":[{"name":"Dipartimento di Meccanica, Politecnico di Milano, 20156 Milano, Italy"}]}],"member":"1968","published-online":{"date-parts":[[2020,4,29]]},"reference":[{"key":"ref_1","unstructured":"(2008). Certification Specifications for Large Aeroplanes, CS25, European Authority in Aviation Safety. Available online: https:\/\/www.easa.europa.eu\/document-library\/certification-specifications."},{"key":"ref_2","unstructured":"(2008). Airworthiness Standards: Transport Category Airplanes, FAR 25."},{"key":"ref_3","unstructured":"Zimmerman, R.E., Warrick, J.C., Lane, A.D., Merritt, N.A., and Bolukbasi, A.O. (1989). Aircraft Crash Survival Design Guide. Volume 3. Aircraft Structural Crash Resistance, Simula Inc.. Tech. Rep."},{"key":"ref_4","first-page":"1","article-title":"Stabilized approach and flare are keys to avoiding hard landing","volume":"23","author":"Rozelle","year":"2004","journal-title":"Flight Saf. Dig."},{"key":"ref_5","unstructured":"Airbus (2007, January 23\u201327). Avoiding hard landings. Proceedings of the 15th Performance & Operations Conference, Puerto Vallarta, Mexico."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"303","DOI":"10.1098\/rsta.2006.1928","article-title":"An introduction to structural health monitoring","volume":"365","author":"Farrar","year":"2006","journal-title":"Philos. Trans. R. Soc. A Math. Phys. Eng. Sci."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"561","DOI":"10.1098\/rsta.2006.1924","article-title":"Fatigue in aerostructures\u2014Where structural health monitoring can contribute to a complex subject","volume":"365","author":"Boller","year":"2006","journal-title":"Philos. Trans. R. Soc. A Math. Phys. Eng. Sci."},{"key":"ref_8","first-page":"51","article-title":"Causes of Injury in Lightplane Accidents","volume":"44","author":"Dehaven","year":"1944","journal-title":"Aero Dig."},{"key":"ref_9","unstructured":"Thomson, R.G., Carden, H.D., and Hayduk, R.J. (1984). Survey of NASA Research on Crash Dynamics, NASA Technical Paper."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"584","DOI":"10.2514\/3.57943","article-title":"NASA\/FAA General Aviation Crash Dynamics Program\u2014A Status Report","volume":"17","author":"Thomson","year":"1980","journal-title":"J. Aircr."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"95","DOI":"10.2514\/2.2739","article-title":"Development of a Scale Model Composite Fuselage Concept for Improved Crashworthiness","volume":"38","author":"Jackson","year":"2001","journal-title":"J. Aircr."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"868","DOI":"10.2514\/3.61569","article-title":"Designing for Aircraft Structural Crashworthiness","volume":"19","author":"Thomson","year":"1982","journal-title":"J. Aircr."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"591","DOI":"10.2514\/3.57944","article-title":"Crash Simulation of Composite and Aluminum Helicopter Fuselages Using a Finite Element Program","volume":"17","author":"Winter","year":"1980","journal-title":"J. Aircr."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Annett, M., and Horta, L. (2011, January 4\u20137). Comparison of test and finite element analysis for two full-scale helicopter crash tests. Proceedings of the 52nd AIAA\/ASME\/ASCE\/AHS\/ASC Structures, Structural Dynamics and Materials Conference, Denver, CO, USA. Collection of Technical Papers.","DOI":"10.2514\/6.2011-1804"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1009","DOI":"10.2514\/3.44631","article-title":"Computer simulation of light aircraft crash","volume":"14","author":"Melosh","year":"1977","journal-title":"J. Aircr."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1568","DOI":"10.2514\/1.27722","article-title":"Application of Probability Methods to Assess Airframe Crash Modeling Uncertainty","volume":"44","author":"Lyle","year":"2007","journal-title":"J. Aircr."},{"key":"ref_17","first-page":"340","article-title":"Validation of numerical simulation of composite helicopter sub-floor structures under crash loading","volume":"Volume 1","author":"Kohlgrueber","year":"1998","journal-title":"Annual Forum Proceedings"},{"key":"ref_18","unstructured":"Jackson, K.E., Boitnott, R.L., Fasanella, E.L., Jones, L.E., and Lyle, K.H. (2004). A History of Full-Scale Aircraft and Rotorcraft Crash Testing and Simulation, NASA. Technical Report."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"485","DOI":"10.1533\/cras.2001.0192","article-title":"Full-scale crash test and simulation of a composite helicopter","volume":"6","author":"Fasanella","year":"2001","journal-title":"Int. J. Crashworthiness"},{"key":"ref_20","first-page":"1292","article-title":"Full-scale crash test of an md-500 helicopter with deployable energy absorbers","volume":"Volume 2","author":"Kellas","year":"2010","journal-title":"Annual Forum Proceedings"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"345","DOI":"10.1016\/S0263-8223(00)00150-1","article-title":"Numerical investigation of a crash test of a composite helicopter subfloor structure","volume":"51","author":"McCarthy","year":"2001","journal-title":"Compos. Struct."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"142","DOI":"10.2514\/2.2908","article-title":"Simulation of Aircraft Landing Gears with a Nonlinear Dynamic Finite Element Code","volume":"39","author":"Lyle","year":"2002","journal-title":"J. Aircr."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"12005","DOI":"10.4050\/JAHS.56.012005","article-title":"Vertical Drop Testing and Analysis of the WASP Helicopter Skid Gear","volume":"56","author":"Fuchs","year":"2011","journal-title":"J. Am. Helicopter Soc."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"483","DOI":"10.4050\/JAHS.49.483","article-title":"Efficient Helicopter Skid Landing Gear Dynamic Drop Simulation Using LS-DYNA","volume":"49","author":"Tho","year":"2004","journal-title":"J. Am. Helicopter Soc."},{"key":"ref_25","unstructured":"Caprile, C., Airoldi, A., Biaggi, A., and Mandelli, P. (1999, January 14\u201316). Multibody Simulation of a Helicopter Landing with Skid Landing Gear in Various Attitude and Soil Conditions. Proceedings of the Twentyfifth European Rotorcraft Forum, Rome, Italy."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1533","DOI":"10.2514\/1.38345","article-title":"Fatigue Life Estimation of Helicopter Landing Probe Based on Dynamic Simulation","volume":"46","author":"Zhu","year":"2009","journal-title":"J. Aircr."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"555","DOI":"10.2514\/1.15507","article-title":"Design of Skid Landing Gears by Means of Multibody Optimization","volume":"43","author":"Airoldi","year":"2006","journal-title":"J. Aircr."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Crist, D., and Symes, L.H. (1981). Helicopter Landing Gear Design and Test Criteria Investigation, Bell Helicopter Textron. Tech. Rep.","DOI":"10.21236\/ADA105512"},{"key":"ref_29","unstructured":"Milwitzky, B., and Cook, F.E. (1953). Analysis of Landing-Gear Behavior, National Advisory Committee for Aeronautics. Tech. Rep."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"031003","DOI":"10.1115\/1.4032286","article-title":"Rotorcraft Hard Landing Mitigation Using Robotic Landing Gear","volume":"138","author":"Kiefer","year":"2016","journal-title":"J. Dyn. Syst. Meas. Control."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Boix, D.M., Goh, K., and McWhinnie, J. (2017, January 3\u20135). Modeling and control of helicopter robotic landing gear for uneven ground conditions. Proceedings of the 2017 Workshop on Research, Education and Development of Unmanned Aerial Systems (RED-UAS), Link\u00f6ping, Sweden.","DOI":"10.1109\/RED-UAS.2017.8101644"},{"key":"ref_32","unstructured":"Gualdi, S., Masarati, P., Morandini, M., and Ghiringhelli, G. (2002, January 17\u201320). A Multibody Approach to the Analysis of Helicopter-Terrain Interaction. Proceedings of the 28th European Rotorcraft Forum, Bristol, UK."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1896","DOI":"10.2514\/1.C032294","article-title":"Helicopter Harsh Landing Events: A Computational Hybrid Methodology to Estimate Fuselage Damage","volume":"50","author":"Vallone","year":"2013","journal-title":"J. Aircr."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"4","DOI":"10.4050\/JAHS.61.042008","article-title":"Experimental Validation of a Computational Hybrid Methodology to Estimate Fuselage Damage Due to Harsh Landing","volume":"61","author":"Sbarufatti","year":"2016","journal-title":"J. Am. Helicopter Soc."},{"key":"ref_35","first-page":"1023","article-title":"Model-based structural integrity assessment of helicopter fuselage during harsh landing","volume":"Volume 2","author":"Giglio","year":"2015","journal-title":"Annual Forum Proceedings"},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"LeBlanc, B., Niezrecki, C., and Avitabile, P. (2010). Structural health monitoring of helicopter hard landing using 3D digital image correlation. Proc. SPIE Health Monitor. Struct. Biolog. Syst., 7650.","DOI":"10.1117\/12.847318"},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Sagi, O., Maynard, D., and Enikov, E. (2011, January 12\u201315). Capacitive transducer for condition based maintenance after harsh landing events. Proceedings of the AUTOTESTCON (Proceedings), Baltimore, MD, USA.","DOI":"10.1109\/AUTEST.2011.6058792"},{"key":"ref_38","unstructured":"Sartor, P., Schmidt, R., Becker, W., Worden, K., Bond, D., and Staszewski, W. (2010, January 19\u201324). Conceptual design of a hard landing indication system using a flight parameter sensor simulation model. Proceedings of the 27th Congress of the International Council of the Aeronautical Sciences 2010, ICAS 2010, Nice, France."},{"key":"ref_39","unstructured":"Sartor, P., Schmidt, R., Menezes, R., Bond, D., and Staszewski, W. (2009, January 9\u201311). Validation and verification of a hard landing indication system for aircraft landing gear. Proceedings of the Structural Health Monitoring 2009: From System Integration to Autonomous Systems\u2014Proceedings of the 7th International Workshop on Structural Health Monitoring, Stanford, CA, USA."},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Liao, L. (2011, January 4\u20137). A study of inertia relief analysis\/Collection of Technical Papers. Proceedings of the AIAA\/ASME\/ASCE\/AHS\/ASC Structures, Structural Dynamics and Materials Conference, Denver, CO, USA.","DOI":"10.2514\/6.2011-2002"},{"key":"ref_41","unstructured":"McPherson, A.E., Evans, J.J., and Levy, S. (1949). Influence of Wing Flexibility on Force-time Relation in Shock Strut Following Vertical Landing Impact, National Advisory Committee for Aeronautics. Technical Report."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/9\/2540\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,13]],"date-time":"2025-10-13T13:51:38Z","timestamp":1760363498000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/9\/2540"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,4,29]]},"references-count":41,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2020,5]]}},"alternative-id":["s20092540"],"URL":"https:\/\/doi.org\/10.3390\/s20092540","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2020,4,29]]}}}