https://hal-enac.archives-ouvertes.fr/hal-00917976Miquel, ThierryThierryMiquelMAIAA - ENAC - Laboratoire de Mathématiques Appliquées, Informatique et Automatique pour l'Aérien - ENAC - Ecole Nationale de l'Aviation CivileReference Airspeed Setting For Time Constrained Descent at Idle ThrustHAL CCSD2013[MATH.MATH-OC] Mathematics [math]/Optimization and Control [math.OC]Porte, Laurence2013-12-12 16:59:092021-10-19 11:02:482013-12-13 15:24:49enConference papersapplication/pdf1This paper addresses the issue of computing a reference airspeed for time constrained descent at idle thrust. More specifically, we will assume a futuristic 4D trajectory application where the air traffic controller will ask an aircraft to overfly a meter fix at a specific time; this time is assumed to be specified by the air traffic controller to settle properly the arrival sequence and could be given for example through an Arrival Manager (AMAN). In addition, this clearance is assumed to be given after the Top Of Descent (TOD) of the aircraft. The aircraft is assumed to descent at idle thrust and has to overfly the meter fix at a given altitude and airspeed to be correctly prepared to land. Idle thrust enables to reduce noise, fuel burn and emissions. A BADA model of an Airbus A320 is used to illustrate the proposed design.