The case study concentrates on new services to air transportation customers. The use case deals with one of the situations that affect directly passengers and where the coordination of all actors has proved to be quite inefficient: due to bad weather conditions at destination airport, a flight is rerouted to another airport. In addition to the stress that raises in passenger minds, there is a cruel lack of information, which let the passengers feel that the situation is not well handled, and there are delays everywhere (disembark, luggage, hotel room, flight connection...), or even worse the passengers are left alone to deal with the situation.
One of the main difficulties that such a crisis management faces is that services and service providers differ from one airport to another and from one flight to another: the coordination of all services needs to be highly flexible.
Nowadays, the quality of service provided to the passenger in such situation is highly dependent on actors and airport. The choreography approach allows domain experts to build a highly flexible workflow that adapts (or are adapted) to services actually available.
Here below, an overall view of the use case is illustrated. First (points 1, 2 and 3 in figure 1), bad weather conditions affect the destination airport and after impact assessment by airport authorities and air traffic control authorities, decision is taken to close temporarily the destination airport. The flight needs then to be rerouted to one of its potential alternate destinations. Those alternate destinations are predefined by the airline operating the flight but the final decision is taken by coordination of air traffic control authorities together with the pilot; a number of parameters may influence the decision such as fuel, weather, and airport congestion. All this part of the scenario is under the management of air traffic control authorities. Civil aviation authorities and their standardisation bodies are in charge of this area of the scenario. Even though this first part of the scenario is very constrained by business policies, choreography could be of interest here.

Figure 1: use case – big picture
In a second part of the use case (points 4 and 5 in figure 1), we focus the objective of our choreographies to optimise the coordination of the various actors and systems involved from the time the decision is taken to reroute the flight to its new destination airport to the time the passengers are able to handle consequences for they journey.
A third step of our scenario starts to involve many more actors (point 6 in figure 1):
Out of these three main actors, a number of dependent organisations/companies will have to be kept informed and coordinated to optimise the management of the crisis. We expect to apply a highly flexible choreography to the coordination of all these second level actors. For the purpose of our scenario, we identify the following actors (we focus on activities that are directly related to passengers; at the proposal stage, we do not show the actors involved in the logistics for the airplane):
Airport companies:
Airline:
And, last but not least, the passenger itself is part of the scenario: he should be kept informed of accurate information at the right time using modern and efficient means. All information displayed to him needs to be accurate and consistent (airport displays, signs even mobile phone SMS). All people dealing with the passenger need to be well prepared with appropriate information and having anticipated passenger arrival to prepare everything in advance (hotel bookings, change of connecting flight if any, new boarding card if any...). In addition, people needing to be kept informed of a flight arrival can be put in the loop as soon as possible: passenger buddy coming to airport to pick him up for example.
The following picture illustrates this third part of the scenario: the emphasis is put on the distribution to the passenger of accurate information concerning luggage, transit if any, hotel, bus. With modern means such as mobile phones, it makes it possible for airline and airport authorities to push up-to-date information directly to the passenger.

Figure 2: use case – third part
The role that choreography plays in the scenario is to provide to domain experts an efficient means to design the coordination of all actors and provide them with accurate means of governance.
Nowadays, the quality of service provided to the passenger in such situation is highly dependent on actors and airport. The choreography approach allows domain experts to build a highly flexible workflow that adapts (or are adapted) to services actually available. This work package evaluates how choreography will help in solving such a flexible environment.