The major Italian contractor, Leonardo, has warned that developing the sixth-generation fighter jet will cost more and take longer than anticipated. The Global Combat Air Programme fighter (GCAP), otherwise known by the British name “Tempest,” is one of the most consequential sixth-generation fighter jets in development outside of the US Air Force’s NGAD fighter. It is currently being jointly developed by Britain’s BAE and Rolls-Royce, Italy’s Leonardo, and Japan’s Mitsubishi Heavy Motors.