The T-34 Mentor, the first primary training aircraft produced for military service after World War II, entered service with the U.S. Air Force in 1950. In 1954, the Navy chose the Beech Aircraft Corporation product to replace the SNJ Texan. A propeller-driven single-engine military trainer, it was later upgraded to the T-34C Turbo-Mentor with a turboprop engine. Pilots in the T-34C experience loops and rolls and reach the milestone of their first solo. Originally delivered as a piston-engine aircraft, the T-34Cs now in service use a Pratt and Whitney PT-6 turboprop for higher performance. The T-34C has served the Naval Air Training Command in training many Naval Aviators and Naval Flight Officers for the U.S. Marine Corps, U.S. Coast Guard, and numerous NATO and Allied nations. After more than 35 years of service, the T-34C is being gradually phased out of the U.S. Navy's inventory and will eventually be replaced by the T-6 Texan Two plane.