A new generation of supersonic transport (SST) aircraft are under development and are aiming to become operational before 2030. While Aerion, a manufacturer with one of the most advanced supersonic programmes, ceased operations in 2021, Boom Supersonic and others continue to develop their supersonic aircraft concepts.
SST aircraft face various challenges, especially due to the ‘sonic boom’ they generate when flying at supersonic speed. For this reason, Concorde was limited to subsonic speeds when flying over land and near coastlines. Furthermore, the high speed of supersonic aircraft is likely to result in an ICAO CO2 standard metric value that is 2 to 3 times higher than comparable subsonic aircraft, and a better understanding is required on the climate change impact from SST non-CO2 emissions at high altitudes.
In the US, a flight demonstrator is being built by NASA to investigate quiet SST technology with the goal to mitigate sonic booms via specifically shaped airframes. Various research projects on SST flight are also being conducted in Europe , and in the regulatory domain EASA is actively working on the development of appropriate noise and emissions standards for SST aircraft at both the European and ICAO level .