DAEDALUS
FLEET ASSIGNMENT OPTIMIZATION SOFTWARE
DAEDALUS is a fleet assignment optimization software. Given a set of flight legs, and a fleet of civil aircrafts, DAEDALUS points the optimal solution, aiming to maximize the generated profit. The proposed approach for the fleet assignment problem is based on a detailed modeling of the financial figures that derive from every possible pairing of flight leg-aircraft available, as well as algorithms for finding the optimal solution in a considerably short amount of time.
The problem of fleet assignment in the airline industry is subject to a big number of parameters, many of which have a strong interdependence. Throughout the last decades, a number of models for solving the fleet assignment problem have been proposed, that aim to optimize the assignment upon different criteria. With DAEDALUS, an attempt has been made to combine the strengths of the most prevalent models, and overcome their weaknesses, in order to provide the basis for an advanced fleet assignment optimization tool.
More specifically, the financial figures that are being modeled are the revenues from ticket sales, cost of fuel, airport charges, crew salaries and navigation fees. For the optimal fleet assignment, the aircraft maintenance routing is taken into consideration, in order to avoid expenses for rerouting aircraft that need to undergo maintenance, to maintenance stations. As for the components of the financial figures, the revenues from ticket sales include a forecasting for passenger demand from data of previous years. The revenues are modeled for different fare classes, for each flight leg. The cost of fuel incorporates the fuel consumption according to the deterioration level of each aircrafts’ engine, and the aircraft weight. The fuel is calculated using CAMACM (Commercial Aircrafts' Mission Analysis Computational Model) developed at the LTT, for a 5 phase mission. The airport expenses include charges for different passenger types, as well as aircraft charges, according to aircraft weight.The pre-processing, and post-processing steps performed by DAEDALUS allow for the optimization of consecutive time periods (e.g. whole day) as well as registering flight hours, maintenance, and engine flight cycles to the aircraft records held by DAEDALUS.
For verification purposes, real case studies have been tested. Our studies have shown that, for a random whole day (24 hours), the optimal fleet assignment proposed by DAEDALUS, generates 25% highest profit than the worst possible solution. Among other results, the sensitivity analysis showed that the precise modeling of the aircraft engine deterioration in combination with aircraft weight - parameters that are often neglected by other fleet assignment models - have a great effect on the fuel consumption, and as a result, on the optimal solution.
The input data DAEDALUS optimization software are
- Itinerary data (timetable, fares)
- Airport data (coordinates, elevation, average seasonal temperature)
- Fleet (fleet types, number of aircraft, aircraft engines)
- Passenger demand from previous years
- Flight crew variable salary (per flight hour)
- Maintenance frequency (for various types of maintenance)
- Regulations imposed by code sharing partners (if applicable)
The aircraft and engine data have been imported by BADA (Base of Aircraft Data), but in case more precise data for specific aircrafts and engines are available, they can easily be incorporated in DAEDALUS database. Based on our analysis, we estimate that for larger fleets (both in number, and aircraft types) the benefits of the model will be considerably higher, since it takes into consideration the characteristics of each fleet type, as well as the engine deterioration for each aircraft.