Mass cancellations overwhelm the data eco system of the aviation industry
By: Matthias Funke
Tags: Aviation, Data

Airlines decide about their schedules twice a year, for their summer (roughly 1 April —31 October) and winter (1 November — 31 March) schedules. Summer and winter (based on the Northern hemisphere) reflect different demand patterns. Nothing stops airlines from having seasonal flights (maybe July-August only) for other marketing reasons.

Empty skies over Europe

They submit their schedules to several places, including:

Their own booking engine (ba.com etc)

Amadeus GDS

Sabre GDS

OAG (a company that publishes a world wide schedule)

IATA

Rather than saying: flight AB 01 from LHR to JFK is daily 0700–1000, they actually submit every single flight that is supposed to take place in the season, so for example 183 flights for a season.

They need to submit a first version of the winter schedule one year ahead of the season, so that people can start booking the flights. This is also called “loading inventory”. Passengers can book up to 330 days in advance. This is managed by the GDSs. (Clearly, this means that every day the limit moves up one day, but it’s not necessary for the airlines to post their flights daily)

As the season approaches, the airline can make adjustments, for example amending the flight times, changing the equipment. They can add more flights anytime, provided they have the slots.

But as soon as a single passenger has booked a single seat on a future flight, removing that flight from the schedule is called a cancellation, and the passenger needs to be contacted to make alternative arrangements, including refunding their ticket. (Regrettably, a cancellation is a lot more time consuming for the airline than a new booking, because the process is not as automated. Archaic ticketing rules need to be read by a human, overruled by a manager on duty, etc.)

Cancellations can happen for many reasons.

The flight is no longer commercially viable (not enough passengers)

Origin or destination airport is closed for departures or arrivals (maintenance, disaster, accident, political reasons, etc.)

Some resource is not available: airworthy plane, healthy and rested flight crew, cabin crew, ground crew, etc.

When a single flight is cancelled, this happens mostly in the 24 hours before departure. A tail (a specific aircraft) has been assigned to the flight and for one of the reasons mentioned above the flight cannot take happen. These types of cancellations need to be posted in the following systems:

Departure control (check-in, load sheet, etc.)

Flight planning (FAA, Eurocontrol, etc.)

Airport systems (departure and arrival)

However, we are now observing mass cancellations due to the unprecedented drop in demand. This is a combination of people not wanting to fly, not being allowed to fly, and not having money to fly. An estimated 60–90% of all flights in the global schedule are currently being cancelled. No-one ever anticipated mass cancellations like this, so the systems are not designed to cope. There are no easy ways of mass cancelling flights. There is no UI anywhere to say: I want to cancel all flights with these flight numbers for the rest of the season.

So many flights stay on some systems.

For the airlines, the first priority in this situation is to prevent new passengers from booking seats on flights that won’t fly, so they don’t need to incur extra expense accommodating these. The second priority is to inform resource planners for crew, cabin crew, catering at origin and destination. The last priority, sadly, is to inform parties like flightradar24.

Would it make sense for flightradar24 to mark “descheduled” flights differently than cancelled flights?

(The author welcomes corrections. He is a data professional, not an airline industry representative.)