until October 1957 and licensed B45 versions built in Canada (125 manufactured by Canadian Car and Foundry), Japan (173 built by Fuji Heavy Industries), and Argentina (75 by FMA) until 1958. Beechcraft delivered the last Model B45s in 1959. Total production of the Continental-engined versions in the US and abroad was 1,904 aircraft. Model 73 Jet Mentor In 1955 Beechcraft developed a jet-engined derivative, again as a private venture, and again in the hope of winning a contract from the US military. The Model 73 Jet Mentor shared many components with the piston-engined aircraft; major visual differences were the redesigned cockpit which was relocated further forward in the fuselage and the air intakes for the jet engine in the wing roots, supplying air to a single Continental J69 jet engine in the rear fuselage. The first flight of the Model 73, registered N134B, was on 18 December 1955. The Model 73 was evaluated by the USAF, which ordered the Cessna T-37, and the USN, which decided upon the Temco TT Pinto. After initial testing at the Naval Air Test Center at NAS Patuxent River, Maryland, the Navy tested the feasibility of using the TT Pinto as a jet-powered trainer for primary flight training in 1959, but discontinued use of the aircraft by December 1960 and discarded all examples, returning to the piston-powered T-34B Mentor and North American T-28 Trojan for its primary flight training requirements. The Beechcraft Model 73 was not put into production and the sole prototype is displayed at the Kansas Aviation Museum. T-34C Turbo-Mentor After a production hiatus of almost 15 years, the T-34C Turbo-Mentor powered by a Pratt & Whitney Canada PT6A-25 turboprop engine was developed in 1973. The original T-34's modified Bonanza/Debonair-style wing was replaced with a variant of the larger Beech Baron wing, and the original Bonanza/Debonair-style landing gear was replaced with the landing gear from the even-larger Beech Duke. Development proceeded at the behest of the USN, which supplied two T-34Bs for conversion. After re-engining with the PT6, the two aircraft were redesignated as YT-34Cs, the first of these flying with turboprop power for the first time on 21 September 1973. Mentor production restarted in 1975 for deliveries of T-34Cs to the USN and of the T-34C-1 armed version for export customers in 1977, this version featuring four underwing hardpoints. The last Turbo-Mentor rolled off the production line in 1990. Since the late