For rational use of the aircraft

AThen the International Air and Space Show in Le Bourget opens its doors on Monday 19 June, the future of air transport has never been so questioned. On the one hand, the needs are exponential, particularly with regard to the aspirations of emerging countries to accelerate their development. On the other hand, the plane is the very incarnation of a carbonaceous world, of which it is urgent to turn the page in order to control climate change. Caught between these two contradictory injunctions, the sector is condemned to make its revolution in an attempt to reconcile them.

Air transport represents only 2.5% of CO emissions₂ global. But this proportion must be put into perspective with the relatively small number of people who use the plane for their travels. Half of the sector’s emissions are thus generated by only 1% of the world’s population. This dichotomy is essential to understand the need to regulate the use of a mode of transport that benefits a few, but which has environmental consequences for all of humanity.

Aeronautics’ efforts to reduce kerosene consumption have been spectacular. The development of more economical engines and the optimization of traffic have enabled energy savings of 80% in half a century. These advances have also contributed to reducing costs in order to offer ever lower prices, which have resulted in a twelve-fold increase in global traffic over the period. If CO emissions₂ per traveler have therefore decreased significantly, but their overall volume is constantly increasing.

Three levers

A race against time has begun between technological advances to reduce CO2 emissions₂ and the rapid growth of global air traffic. More than 46,000 new aircraft will be put into service over the next two decades to meet an annual increase in the number of travelers of almost 4%. This growth will only be sustainable if the sector manages to quickly find solutions for its decarbonization.

Three levers can be operated. Sustainable fuels for aviation are a promising avenue, but it will not be enough. Beyond the high cost of their manufacture, their growth may also come up against production capacities that are not infinitely expandable. Second lever, energy efficiency gains, in particular thanks to hydrogen. But innovations will take time to reach the industrial stage and the replacement of kerosene on long-haul flights is still science fiction.

There remains the third lever: regulating the volume of traffic. We must be wary of an overly European-centric vision, consisting in drastically limiting the capacities of the sector. In many emerging countries, the plane is the only way to connect destinations within their own borders, due to a lack of alternative transport infrastructure. It seems unlikely that India or the African countries will be ready to sacrifice their development on the altar of sobriety demanded by the rich countries.

Before considering radical measures such as setting individual flight quotas – some suggest this – it is urgent to change the way we fly. “The plane is necessary, but it must be made acceptable through reasoned use”, believes Augustin de Romanet, CEO of Groupe ADP. It is on this notion of “reasonedness” that the debate must now focus.