Turbo-Union RB199 is a three-spool, reheated turbofan family developed collaboratively by Rolls-Royce, MTU Aero Engines, and Avio Aero for the Panavia Tornado. It entered service in 1979, delivered more than 2,500 engines, accumulated over 7 million flight hours, and reaches about 16,000 lb thrust with reheat; its compact high-thrust-to-weight design was tailored to the Tornado. The family currently supports German, Italian, and Saudi Tornado fleets, while the RAF Tornado fleet has retired. Exact RB199-34R variants and Tornado relationships remain separate identities.