envisioned. The United States Army Air Force bought 83 L-17As from North American in 1946, as a liaison and staff transport aircraft, with 36 going to the Army and 47 to the National Guard. These were supplemented by 163 L-17Bs from 1948, which were ordered by the United States Air Force on behalf of the Army and National Guard, with 129 going to the Army and the rest to the National Guard. During the Korean War, the US Army's Navions added casualty evacuation and forward air controller to the aircraft's liaison and light transport duties. The Navion was phased out of front line service by 1957, with the aircraft handed over to the Civil Air Patrol or used as hacks. Present day , many Navions are still flying and there is an active Navion owners community. On 18 March 2003 Sierra Hotel Aero Inc of South St. Paul, Minnesota purchased the type certificate, design data, molds and tooling. Company stated in January 2013, that it was two to three years away from bringing the aircraft back into production. In the meantime Sierra Hotel Aero is carrying out re-manufacturing and upgrading for some owners of Navions. Variants North American NA-143 Two prototypes. North American NA-145 Navion North-American-built production aircraft, 1,027 built. North American NA-154 Navion Military version for the United States Army as the L-17A, 83 built. Ryan Navion Ryan-built production aircraft, 600 built. Ryan Navion A Improved Navion with a 205hp Continental E-185-9 engine, 602 built. Ryan Navion B Modified for the higher powered 260hp Lycoming GO-435-C2 engine, also known as the Super Navion 260, 222 built. Tusco Navion D Conversion by Tulsa Manufacturing Company with a 240hp Continental IO-470-P engine and tip tanks. Tusco Navion E Conversion Tulsa Manufacturing Company with a 250hp Continental IO-470-C engine and tip tanks. Tusco Navion F Conversion Tulsa Manufacturing Company with a 260hp Continental IO-470-H engine and tip tanks. Navion G Rangemaster Redesigned aircraft by Navion Aircraft Company with 260hp Continental IO-470H engine, integral cabin and tip tanks, 121, some built as the Rangemaster G-1 with a modified fin. Navion H Rangemaster Navion G with a 285hp Continental IO-520B engine, 60 built, an additional aircraft was built by the Navion Rangemaster Aircraft Company in 1974. Ryan Model 72 One Navion B was modified as two-seat trainer for a United States Navy competition with the Temco Model 33 Plebe. Camair Twin Navion twin engine