tailieunhanh - Scheduling for operations airline (2nd edition): Part 2

Continued part 1, part 2 of the Scheduling for operations airline (2nd edition) present the content: airline irregular operations, gate assignment, aircraft boarding strategy, computational complexities and simulation, computational complexity, Heuristics and software, start-up airline case study, manpower maintenance planning, aircraft tow-tugs, runway capacity planning, small aircraft transportation system. | Chapter 10 Airline Irregular Operations Introduction Aircraft mechanical problems severe weather crew sickness airport curfews and security are among the problems that force an airline to delay or even cancel their regular published flights. On an average day in the United States approximately 15-20 of all flights experience significant delays more than 15 minutes and approximately 1-3 of all flights are cancelled Yu et al. 2003 . The scheduling methodologies described in Chapters 6 and 7 provide an airline with a very efficient plan high utilization of resources and very tight aircraft and crew assignments. In many cases a small perturbation in this plan such as unavailability of an aircraft or crew results in major disruption to the scheduled flights. The airlines adopt a combination of tactics such as flight delays flight cancellations aircraft substitutions ferry flights flying an empty aircraft to a point of need and aircraft diversions to return to their published scheduled flights as soon as possible. Since these activities are not pre-planned and occur only when there is a disruption in the schedule they are called irregular operations. The recovery time can span from the time the disruption occurs up to the time the airline gets back to its original schedule. In practice the two problems of aircraft recovery and crew reassignment are handled separately Jarrah Yu 1993 . The airlines that are faced with disruption first attempt to develop a feasible flight rerouting through some of the tactics mentioned above. This new rerouting schedule is checked for crew assignment feasibility. If a feasible crew assignment does not exist a new rerouting schedule is developed. This process continues until a feasible rerouting and crew reassignment is found. This chapter examines the daily aircraft rerouting schedules for single fleet only. See the list of references for models that examine multi-fleet and crew reassignment. The aircraft-schedule recovery problem is .