Real-time Slot Management with Web Services

More and more airports become slot coordinated nowadays – but two obstacles apply hereby: First, this information exchange between airlines and airport coordinator is still done manually on an email base. Second, this process produces useless waste response times. The solution for the first deal breaker are slot management tools. The solution for the second obstacle are web services, which is the main topic for the following blog.

Slot Management within airlines

The task of a slot manager for airlines can be high-level summarized as this:

  • Optimization of initial slot submission and ongoing management of slot portfolio
  • Securing valuable slot assets
  • Schedule optimization, by identification of unused slots and inconsistencies between flight schedule and given slots.
  • Managing ad-hoc changes such as cancellations, delays, etc.

For the last task the following applies: When making ad-hoc changes, the airline focuses on getting aircraft and crew in place in order to get passengers to their destination. The slot managers’ responsibility therefore is to get them the slots needed in time for flights to operate via communication with the respective slot coordinators. Not getting the needed slots in time may result in having to re-schedule flights, incurring operational costs that affect profitability and the passenger sentiment. Not well organized and untimely slot management truly has a deep impact on an airline’s financial performance. Waiting usually costs the airline money.

Significant increase of schedule changes volume

Looking at today´s situation, efficient management and monitoring of airport slots is getting more and more challenging. Airline traffic grows rapidly and traffic congestions become a critical issue. The result: More and more airports become slot coordinated to manage this development. This also affects airlines who on one hand need to comply with increasing slot regulations. Moreover airlines are confronted with increasing schedule / operational changes during the season resulting in an increased number of change messages. This implies a high volume of communication efforts that need fast and efficient routines.

But many airlines face two deal breakers nowadays: First, this information exchange between airlines and the airport coordinator is still done manually on an email base. Second, this process produces useless waste response times.

The solution for the first deal breaker are slot management tools. All current applications on the market provide airlines support in managing their slots at airports that are coordinated according to the IATA Worldwide Scheduling Guidelines procedures and SSIM Chapter 6 formats. Airlines use them because they provide support in automating the slot coordination process and to control the increasing complexity.

The solution for the second obstacle are web services, which will be discussed in the following.


What are web services?

Web services are offered via web portals, for example OCS, eAirportSlots, by airport coordinators and the functionality offered via web-services will be extended step by step in the near future. They represent a new and much more efficient way for slot communication. More efficient, because they utilize standard IATA XML messages, which offer a standardized way of requesting slots and receiving fast answers. The solution for a more efficient slot communication process is therefore to integrate the web services into the slot management application.

Ideally the range of slot related information transported via web services shall cover:

  • slot information (SIR)
  • slot clearance (SAQ, SCR)
  • runway capacity
  • waitlist handling (WCR, WIR)

Let’s therefore have a closer look at how web services can tremendously improve the communication efficiency.

Slot Management without web services

To demonstrate, how web services can be of benefit for the slot management of an airline, we examine the day to day tasks of a slot manager. Let's take a look at slot manager Anna and her typical work scenario:

Anna would like to request a new slot, but wants to check upon the availability first. That’s why she will send an SAQ message on her slot management solution via SITA or email to the respective airport coordinator. What happens next?

Anna will have to wait for a reply of the airport coordinator – this might take a while, especially if the requested slot is not available. Let´s say one hour.

Dependent on the answer, Anna would like to explore further possibilities which might lead to further SAQ requests and additional waiting time. In the end she writes an SCR message, typically via email, in order to request the best available slots based on her investigation.

Altogether we assume that Anna has to wait some time and needs multiple steps to finalize her work. This is – so to say – inefficient waste time for that particular situation that can be omitted easily with web services.

Slot Management with web services

Let´s come back to Anna and look, how web services would facilitate her work. It is very easy: For all her actions we can omit the “she has to wait for a reply”-part. This in turn means: For the SCR message she can immediately check upon the slot availability while creating the request.

Even continuing with this scenario: With web services, Anna gets an immediate answer from the airport coordinator, including alternatives, refusal reasons and detailed information of the constraints that prevent a coordination, in case of any unavailability for her requested slot. This allows her a better and faster decision. She can straight away request and clear a new slot based on the information received – and immediately gets an answer for her request.

With the use of web services Anna is easily able to finish her day to day tasks with the best possible result and almost in real-time updated data – no waste time in between. No waiting for a reply. Slot coordination in almost real-time.


The advantages of using web services instead of telexes are obvious.
It is possible to

  • change slots directly online
  • considering additional information regarding possible constraint violations and availabilities in order to find the optimal solution
  • view/download immediate waitlist information & slot monitoring information
  • view airport slot availability
  • achieve a higher quality of slot portfolio

As a result web services allow slot managers to make their decisions faster and based on additional information. Thus they can better control the effects of slot-based disruptions by more quickly respond to rescheduling and evaluating alternatives. The time spent on slot management will be significantly reduced and the collaboration with airports improved.

Bottom line: The use of web services is the next step towards a more efficient real-time slot management. That´s why we expect this trend for web services to be expanded in the future becoming state-of-the art for slot communication.

If you like to get to know more about how real-time slot management via web services or even would like to get a demonstration, please send us a message via our LinkedIn profiles.