{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T05:41:43Z","timestamp":1792561303498,"version":"4.5.0"},"reference-count":41,"publisher":"Wiley","license":[{"start":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T00:00:00Z","timestamp":1792454400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T00:00:00Z","timestamp":1792454400000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"funder":[{"DOI":"10.13039\/501100002946","name":"Deutsches Zentrum f\u00fcr Luft- und Raumfahrt","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100002946","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Journal of Sleep Research"],"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>Time awake affects airline pilots' fatigue but it is less clear how workload during that time awake impacts fatigue. Although current flight time limitations take the number of flights within a duty period as a measure of workload into account, quantitative evidence for its fatiguing effect is scarce. Here, we analysed fatigue, subjective workload and flight\u2010associated hassles at the end of 553 short\u2010haul flights from 37 airline pilots. Two linear mixed\u2010models with fatigue or subjective workload as the dependent variable were generated, adjusted for time awake, number of completed flights, number of hassles, prior sleep and pilot's responsibility (flying\/monitoring). Results showed that fatigue was influenced by time awake, number of flights and pilot's responsibility, whereas no effect was found for number of hassles. The critical fatigue threshold (flying not recommended) was exceeded 2.4\u2009h earlier when operating four flights compared with one flight. Fatigue was lower but subjective workload was higher when the pilot was flying instead of monitoring. Subjective workload increased with number of hassles, but not with number of flights or time awake. European duty time limitations are justified to include a penalty for additional flights but may underestimate the fatiguing effect.<\/jats:p>","DOI":"10.1111\/jsr.70473","type":"journal-article","created":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T05:05:59Z","timestamp":1792559159000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Additive Effects of Time Awake and Number of Flights on Fatigue in Short\u2010Haul Pilots: Implications for Duty Time Regulation"],"prefix":"10.1111","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2122-3938","authenticated-orcid":false,"given":"Dorothee","family":"Steven","sequence":"first","affiliation":[{"name":"Department of Sleep Und Human Factors Research, Institute of Aerospace Medicine German Aerospace Center  Cologne Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kristjof","family":"Tritschler","sequence":"additional","affiliation":[{"name":"Germanwings GmbH  Cologne Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8453-0812","authenticated-orcid":false,"given":"Mathias","family":"Basner","sequence":"additional","affiliation":[{"name":"Unit for Experimental Psychiatry, Division of Sleep and Chronobiology, Department of Psychiatry University of Pennsylvania Perelman School of Medicine  Philadelphia Pennsylvania USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0336-6705","authenticated-orcid":false,"given":"Eva\u2010Maria","family":"Elmenhorst","sequence":"additional","affiliation":[{"name":"Department of Sleep Und Human Factors Research, Institute of Aerospace Medicine German Aerospace Center  Cologne Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6054-5753","authenticated-orcid":false,"given":"Daniel","family":"Aeschbach","sequence":"additional","affiliation":[{"name":"Department of Sleep Und Human Factors Research, Institute of Aerospace Medicine German Aerospace Center  Cologne Germany"},{"name":"Institute of Experimental Epileptology and Cognition Research University of Bonn Medical Center  Bonn Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,10,20]]},"reference":[{"key":"e_1_2_12_2_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.sleh.2023.07.013"},{"key":"e_1_2_12_3_1","doi-asserted-by":"publisher","DOI":"10.3109\/00207459008994241"},{"key":"e_1_2_12_4_1","doi-asserted-by":"publisher","DOI":"10.1111\/jsr.13305"},{"key":"e_1_2_12_5_1","doi-asserted-by":"publisher","DOI":"10.1093\/aje\/kws219"},{"key":"e_1_2_12_6_1","doi-asserted-by":"publisher","DOI":"10.1111\/jsr.13521"},{"key":"e_1_2_12_7_1","doi-asserted-by":"publisher","DOI":"10.18637\/jss.v067.i01"},{"key":"e_1_2_12_8_1","first-page":"1072","article-title":"Perceived Fatigue for Short\u2010 and Long\u2010Haul Flights: A Survey of 739 Airline Pilots","volume":"74","author":"Bourgeois\u2010Bougrine S.","year":"2003","journal-title":"Aviation, Space, and Environmental Medicine"},{"key":"e_1_2_12_9_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.trpro.2017.12.163"},{"key":"e_1_2_12_10_1","doi-asserted-by":"publisher","DOI":"10.1080\/00140139308967974"},{"key":"e_1_2_12_11_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.neubiorev.2018.10.024"},{"key":"e_1_2_12_12_1","doi-asserted-by":"publisher","DOI":"10.3357\/ASEM.2435.2009"},{"key":"e_1_2_12_13_1","unstructured":"EASA.2014.\u201cORO.FTL.205 Flight Duty Period (FDP). Understanding EASA ORO.FTL 2016.\u201dhttps:\/\/understandingeasa2016ftl.wordpress.com\/easa\u2010ftl\/oro\u2010ftl\/oro\u2010ftl\u2010205\u2010flight\u2010duty\u2010period\u2010fdp\/."},{"key":"e_1_2_12_14_1","doi-asserted-by":"publisher","DOI":"10.3357\/ASEM.2382.2009"},{"key":"e_1_2_12_15_1","unstructured":"Gander P. H. R. C.Graeber H. C.Foushee J. K.Lauber andL. J.Connell.1994.\u201cCrew Factors in Flight Operations 2: Psychophysiological Responses to Short\u2010Haul Air Transport Operations.\u201dhttps:\/\/ntrs.nasa.gov\/citations\/19950009235."},{"key":"e_1_2_12_16_1","doi-asserted-by":"publisher","DOI":"10.1111\/jsr.12197"},{"key":"e_1_2_12_17_1","doi-asserted-by":"publisher","DOI":"10.3357\/ASEM.3963.2014"},{"key":"e_1_2_12_18_1","doi-asserted-by":"publisher","DOI":"10.1002\/sim.3107"},{"key":"e_1_2_12_19_1","doi-asserted-by":"publisher","DOI":"10.3357\/AMHP.5236.2019"},{"key":"e_1_2_12_20_1","first-page":"139","volume-title":"Advances in Psychology","author":"Hart S. G.","year":"1988"},{"key":"e_1_2_12_21_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.aap.2013.10.010"},{"key":"e_1_2_12_22_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.aap.2015.10.005"},{"key":"e_1_2_12_23_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.clinph.2006.03.011"},{"key":"e_1_2_12_24_1","doi-asserted-by":"publisher","DOI":"10.3389\/fenvh.2024.1362755"},{"key":"e_1_2_12_25_1","doi-asserted-by":"publisher","DOI":"10.1080\/07420520601085925"},{"key":"e_1_2_12_26_1","first-page":"46","article-title":"Psychische Belastung und Beanspruchung \u2010 Untersuchung der Sensitivit\u00e4t des NASA\u2010TLX und NASA\u2010TLX\u2010ZEIS bei einer Flugf\u00fchrungsaufgabe","volume":"56","author":"Pfendler C.","year":"2002","journal-title":"Zeitschrift f\u00fcr Arbeitswissenschaft"},{"key":"e_1_2_12_27_1","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pcbi.1005759"},{"key":"e_1_2_12_28_1","doi-asserted-by":"publisher","DOI":"10.3357\/ASEM.2362.2008"},{"key":"e_1_2_12_29_1","first-page":"698","article-title":"Pilot Fatigue in Short\u2010Haul Operations: Effects of Number of Sectors, Duty Length, and Time of Day","volume":"78","author":"Powell D. 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P.Perelli.1982.\u201cEstimating Aircrew Fatigue: A Technique with Application to Airlift Operations.\u201d"},{"key":"e_1_2_12_36_1","first-page":"888","article-title":"The Influence of Workload Factors on Flight Crew Fatigue","volume":"2","author":"Tritschler K.","year":"2010","journal-title":"International Air Safety Seminar Proceedings"},{"key":"e_1_2_12_37_1","doi-asserted-by":"publisher","DOI":"10.3357\/AMHP.4587.2016"},{"key":"e_1_2_12_38_1","doi-asserted-by":"publisher","DOI":"10.1093\/sleep\/26.2.117"},{"key":"e_1_2_12_39_1","doi-asserted-by":"publisher","DOI":"10.3357\/ASEM.3670.2013"},{"key":"e_1_2_12_40_1","doi-asserted-by":"publisher","DOI":"10.1111\/jsr.12186"},{"key":"e_1_2_12_41_1","first-page":"843","article-title":"Recommended Amount of Sleep for a Healthy Adult: A Joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society","volume":"38","author":"Watson N. 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