Merging of flights

Meet Marie & Felix

The joy of the common destination does not last long, because in the departure hall, they find that they are booked on different flights to Berlin. They had so much to talk about and assumed that they would fly in the same plane and possibly get two seats next to each other.

But Marie flies to Berlin at 6:10 am with the airline FGH and Felix at 6:15 am with the airline CDE. Marie has a customer mileage card with FGH and Felix has been booked by "his" NGO according to their incentive contract with the airline CDE.


After their arrival in Berlin, Marie and Felix telephoned again for a short time and exchanged information about their respective flights.

They found it a pity that they could not fly together on the same plane, especially as there were still a few places left on each flight.

Sensitized by the Fridays4Future activities, the two ask themselves the following questions :

  • The CO₂ footprint of Marie and Felix – which size has it in the smaller aircraft and which one in the larger aircraft?

  • Why do you send two parallel aircraft on the same route in parallel, instead of using a larger aircraft, in which all passengers of the two flights would have found a place?

  • How could a (future) shair flight schedule look like?

For Marie’s and Felix’ route the following "formula" applies:

The smaller the aircraft, the bigger the CO₂ footprint.

Stuttgart – Berlin-Tegel

not true to scale

The saving in kerosene consumption is about 15%. The same percentage applies to the reduction of CO₂ emissions as well. 

shair is derived from “share an aircraft”. It is a B2B business model in which two or more (competing) airlines share (an) aircraft(s). 

The business magic word for such an optimization is called co-opetition.

Co-opetition is a term from the business strategy teaching and represents a combination of the terms cooperation and competition, so a blending strategy in between cooperation and competition (Gabler Lexicon). 


The simplest shair solution is to replace the flight of Marie and Felix with a shair flight. In case of low demand, e.g. the mechanism "turn 2 into 1" in question, with high load factors "turn 3 into 2". 

At low load factors, for example, the mechanism "turn 2 into 1" in question, with high utilization "turn 3 into 2”.

The concrete design of the route Stuttgart - Berlin-Tegel is quite spectacular (see statistics at the bottom): instead of 15 daily flights only 10 or at most 11 in each direction - 15% less CO2 emissions included.

As an example, Easyjet has the following seating capacities according to aircraft types:

Easyjet: A319-100
156 seats, factor 3 --> 468 seats

235 seats, factor 2 --> 470 seats


On the capacity side, the mechanism "turn 2 into 1" is the ideal constellation.

With low utilization, e.g. the mechanism "turn 2 into 1" in question, but with high utilization "turn 3 into 2".

The specific layout of the Stuttgart - Berlin-Tegel route is quite spectacular (see statistics at the bottom), instead of 15 daily flights, only 10 or at most 11 in each direction - that is 15% less CO₂ emissions.

If (shair) succeeds in using an A321neo instead of a (“classic”) A321, CO₂ emissions would be up to 50% lower than today's supply. And even if it is 40% "only", it should be worth a try. A prototype could be implemented within 9 to 12 months.

Marie and Felix are looking forward to it – and with them not only the children on our earth.

This could be the future flights scenario Stuttgart – Berlin-Tegel, where Marie and Felix could sit together in a shair plane:


Flights Stuttgart – Berlin-Tegel 

23.08.2019 – Comparism in between actual flights versus shair

10 or 11 daily flights instead of 15