The ATJ-process is a chemical process that converts ethanol to Sustainable Aviation Fuel (SAF). The yield from this process is about 90% SAF and 10% biodiesel. The ATJ-process is one of five technologies certified by ASTM to deliver biofuels to the aerospace industry. SAF produced via the ATJ-process does not need further processing and can be mixed directly into the fossil fuel. The first commercial flights with fuel produced in this way were made in October 2018.