In 2019, ICAO held the first Stocktaking Seminar toward the 2050 Vision for Sustainable Aviation Fuels. This event provided a forum for the exchange of information and was the first step towards the establishment of a quantified 2050 ICAO Vision for Sustainable Aviation Fuels. Building upon the success of this event, ICAO is organizing a Stocktaking Seminar on aviation in-sector CO2 emissions reductions. This will provide an opportunity to quantify the contribution of current and future aircraft technologies, operational improvements, and sustainable aviation fuels towards reducing aviation CO2 emissions.
The 40th ICAO Assembly requested the continued exploration "of a long-term global aspirational goal for international aviation" (Resolution A40-19, paragraph 9). Based on this request, the information received through submitted questionnaires will feed into ICAO's work on assessing the feasibility of a Long Term Aspirational Goal (LTAG) for international aviation. A general timeline for the LTAG work programme is presented below:

The questionnaire is available to download as a MS Word document and as a PDF: