BAC One-Eleven BAC One-Eleven The British Aircraft Corporation One-Eleven, also known as the BAC-111 or BAC 1-11, is a British short-range jet airliner used during the 1960s and 1970s. It was the second short-haul jet airliner to enter service, following the French Sud Aviation Caravelle. The aircraft was also produced under licence in Romania during the 1980s as the Rombac One-Eleven. The One-Eleven was conceived by Hunting Aircraft and developed by the British Aircraft Corporation when Hunting merged into BAC along with other British aircraft manufacturers in 1960. The One-Eleven was intended to replace the turboprop Vickers Viscount on short-range routes. The
Turboprop in the experimental Consolidated Vultee XP-81. The XP-81 first flew in December 1945, the first aircraft to use a combination of turboprop and turbojet power. The technology of the Allison's earlier T38 design evolved into the Allison T56, with quartets of the T56s being used to power the Lockheed Electra airliner, its military maritime patrol derivative the P-3 Orion, and the widely produced C-130 Hercules military transport aircraft. One of the most produced turboprop engines used in civil aviation is the Pratt & Whitney Canada PT6 engine. The first turbine-powered, shaft-driven helicopter was the Kaman K-225, a development of Charles