Formation flight in civil aviation

Formation flight in civil aviation

Verhagen, C.M.A.

Visser, H.G. (mentor)

Aerospace Engineering

Air Transport Operations

Control and Operations

2015-07-17

A model has been developed to demonstrate the value of a decentralized approach to formation flight routing. In the considered scenario, formation flight is an in-flight option. While centralized approaches are well covered in the literature, anticipating the use of formation flight before take-off, decentralized approaches have received less attention. Several examples do exist, noting that only one completely decentralized method was encountered. A completely decentralized approach is herein defined as one that does not use any kind of pre-flight formation flight planning or routing restrictions. While flying, each aircraft may communicate with others when they breach each other's communication range. During these communications, a formation flight strategy is formulated and the flights have to choose directly if they wish to commit to it. This method of obtaining fuel savings characterizes this work. Its compactness allowed for a broad evaluation of the potential of a decentralized approach within the project time frame. The sub-optimality of this greedy method enhances the value of any positive findings from this research, since it is likely that a global optimum has not yet been found. The decentralized approach that was developed during this project shows promising results when considering the efficiency with which large scenarios can be evaluated. A typical simulation in the performed transatlantic case study, containing 347 flights, took less than 6 minutes on a standard PC. Additionally, the capability of the model to sustain obtained savings when flights are delayed has been shown. The ability of flights to perform multiple consecutive formation flight segments is new to the research area. The latter significantly increases the usage rate of formation flight in the considered scenarios. It is noted that, in any current publication on formation flight implementation, the estimation of overall fuel savings strongly depends on assumptions. As such, the added value of this research is of a more relative nature. Based on the conservative assumption that any formation member other than the formation leader experiences a fuel flow reduction of 10%, the resulting routes and used formations were studied. The maximum obtained overall fuel savings estimation is 4.3% in a case study on 347 transatlantic flights. These savings were found when a combined objective was used, taking into account both fuel consumption and additional flight time. More significantly, formation sizes ranging from 2 to 6 aircraft were commonly used. A formation flight usage rate of 73%, with respect to total flight time, was recorded during the same simulation.

formation flight
decentralized approach
implementation
routing
greedy algorithm
fuel savings

http://resolver.tudelft.nl/uuid:44cc6034-e974-4306-a540-9195a48322f8

Student theses

master thesis

(c) 2015 Verhagen, C.M.A.