Chase YC - 122 Avitruc The Chase XCG - 18A and YC - 122 Avitruc ( known internally as the Chase MS . 8 ) was a military transport aircraft designed by Chase Aircraft and produced in limited numbers in the United States in the late 1940s , initially as a glider , but definitively in powered form . The design was based on the CG - 14 cargo glider but was substantially larger and featured all - metal construction . it was a high - wing cantilever monoplane of twin boom configuration . The fuselage was of rectangular cross - section and featured a loading ramp at its rear . The main undercarriage units were carried at the sides of the fuselage and were fixed , while the nosewheel was retractable . In its powered form , two radial engines were fitted in nacelles in the wings . Design and development . The USAAF ' s experiences with cargo glider s during World War II indicated a role for a similar aircraft in the post - war inventory , but one capable of carrying a substantially heavier load and with greater recoverability than the essentially expendable wartime wooden assault gliders . Chase ' s CG - 14 was selected as a starting point , and in January 1947 , the USAAF placed an order for an enlarged , metal version of this aircraft , initially designated XCG - 14B but redesignated to XCG - 18A to reflect the basically all - new nature of the aircraft . When the prototype flew that December , it was the world ' s first all - metal transport glider . One of the major improvements was the use of a thinner wing section which allowed high tow speeds and small aircraft like the P - 47 fighter being able to tow it into the air and to its release point . Operational history . In March 1948 , the service ( now the USAF ) ordered four more aircraft under the new designation XG - 18A and a fifth to be fitted with engines as the YC - 122 . The air force eventually lost interest in purchasing assault gliders , but continued with the development of the powered variant , purchasing two more examples for evaluation as the YC - 122A and redesignating the second of these as the YC - 122B when the original Pratt & Whitney engines were swapped for Wright units . This aircraft would form the basis for the definitive service trials version , the YC - 122C . Nine of these aircraft were ordered and although they performed well in evaluation ( first at Sewart AFB , Tennessee , later at Ardmore AFB , Oklahoma ) , the USAF no longer saw a need for a small transport aircraft and cancelled the project . Despite the short - lived history of the aircraft , it was used extensively at Ardmore AFB . At least one pilot , Captain Phillip C . Gromley of the 16th Troop Carrier Squadron , 463rd Troop Carrier Wing , achieved 1000 hours piloting the plane by February , 1955 . All aircraft were replaced by Fairchild C - 123B Providers by July , 1955 . The last YC - 122C assault transport was flown to Tucson , Arizona , August 30 , 1955 , for storage at Davis - Monthan AFB . Captain Gromely is recorded as making the final flight of a YC - 122C to Tucson . The remaining machines served on in utility roles until 1957 . Following their retirement , the fuselage of one of the YC - 122s was used in the construction of the Hiller X - 18 .