{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T21:12:18Z","timestamp":1773436338782,"version":"3.50.1"},"reference-count":52,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2019,8,13]],"date-time":"2019-08-13T00:00:00Z","timestamp":1565654400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>The use of apron buses has become a common practice at many European airports. Previous studies related to airplane boarding rarely apply when apron buses are used, leaving airlines with no well-researched option except to use the random boarding method. In this paper, we test the time to complete boarding a two-door airplane using various boarding methods with two apron buses. These methods were inspired by the classical outside-in, back-to-front, and reverse-pyramid methods considering the limited number of boarding groups corresponding to the limited number of apron buses used for transporting passengers from the terminal to the aircraft. Unlike earlier publications, we test these methods under partial aircraft occupancy. Furthermore, we test the boarding methods under conditions involving: different passenger occupancy rates, different luggage situations, and with two types of seating assignments\u2014random and based upon passenger seating preferences\u2014by considering the advantages brought by the symmetric layout of the aircraft. Experimental results indicate that the best performing method can reduce the boarding time by up to 38.6% compared to the time resulting from the random boarding method. When the airplane is partially occupied, the best performing methods are reverse pyramid\u2013A, hybrid\u2013A, and hybrid\u2013B, all with similar performances.<\/jats:p>","DOI":"10.3390\/sym11081044","type":"journal-article","created":{"date-parts":[[2019,8,14]],"date-time":"2019-08-14T03:59:26Z","timestamp":1565755166000},"page":"1044","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Testing New Methods for Boarding a Partially Occupied Airplane Using Apron Buses"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4192-183X","authenticated-orcid":false,"given":"Liviu-Adrian","family":"Cotfas","sequence":"first","affiliation":[{"name":"Department of Economic Informatics and Cybernetics, Bucharest University of Economic Studies, 010552 Bucharest, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3589-1969","authenticated-orcid":false,"given":"Camelia","family":"Delcea","sequence":"additional","affiliation":[{"name":"Department of Economic Informatics and Cybernetics, Bucharest University of Economic Studies, 010552 Bucharest, Romania"}]},{"given":"R. John","family":"Milne","sequence":"additional","affiliation":[{"name":"David D. Reh School of Business, Clarkson University, 333 B.H. Snell Hall, Potsdam, NY 13699, USA"}]},{"given":"Mostafa","family":"Salari","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, Schulich School of Engineering, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada"}]},{"given":"Liliana","family":"Cr\u0103ciun","sequence":"additional","affiliation":[{"name":"Department of Economics and Economic Policies, Bucharest University of Economic Studies, 010374 Bucharest, Romania"}]},{"given":"Anca Gabriela","family":"Mol\u0103nescu","sequence":"additional","affiliation":[{"name":"Department of Economics and Economic Policies, Bucharest University of Economic Studies, 010374 Bucharest, Romania"}]}],"member":"1968","published-online":{"date-parts":[[2019,8,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Delcea, C., Cotfas, L.-A., Chiri\u021b\u0103, N., and Nica, I. (2018). A Two-Door Airplane Boarding Approach When Using Apron Buses. 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