Length: 12"
Code: NC10210

The first flight of the Model 45 was on 2 December 1948, by Beechcraft test pilot Vern Carstens. In 1950 the USAF ordered three Model A45T test aircraft, which were given the military designation YT-34.[2] A long competition followed to determine a new trainer, and in 1953 the Air Force put the Model 45 into service as the T-34A Mentor, while the USN followed in May 1955 with the T-34B. The US Air Force began to replace the T-34A at the beginning of the 1960s, while the U.S. Navy kept the T-34B operational until the early 1970s. As of 2007, Mentors are still used by several air forces and navies.

The T-34C was used by the Argentine Navy during the Falklands War.

In 2004, due to a series of crashes involving in-flight structural failure during simulated combat flights, the entire US civilian fleet of T-34s was grounded by the Federal Aviation Administration. The grounding has since been eased to a series of restrictions on the permitted flight envelope.

The T-34C is still used as the primary training aircraft for United States Navy and Marine Corps pilots. The T-34C is currently being replaced by the T-6 Texan II but is still the primary aircraft at NAS Corpus Christi and NAS Whiting Field. NAS Pensacola has already completed the transition to the T-6 and the first T-6s are scheduled to arrive at Whiting Field in summer 2009.

NASA Dryden Flight Research Center has operated two T-34C aircraft. The first was previously flown at the Glenn Research Center in Cleveland, Ohio, for propulsion experiments involving turboprop engines, and then came to Dryden as a chase aircraft in 1996. That aircraft was returned to the US Navy in 2002. Dryden obtained its second T-34C in early 2005 from the Navy's Air Warfare Center Aircraft Division at NAS Patuxent River, where it was due to be retired. At Dryden, the T-34C is primarily used for chasing remotely piloted unmanned air vehicles which fly slower than NASA's F-18's mission support aircraft can fly. It is also used for required pilot proficiency flying.

The United States Army received six ex-US Navy T-34C, used as test platforms and chase planes at Edwards Air Force Base and at Fort Bragg.

The Mentor is the aircraft used by the Lima Lima Flight Team and Dragon Flight, both civilian demonstration teams. It is also used by aerobatic pilot Julie Clark, who flies her T-34 "Free Spirit" (registration N134JC) at air shows.