{{Short description|1940s military transport aircraft}} {{Use American English|date=April 2026}} <!-- This article is a part of Wikipedia:WikiProject Aircraft. Please see Wikipedia:WikiProject Aircraft/page content for recommended layout. --> {{Infobox aircraft |name=XG-18/YC-122 Avitruc |image= File:Chase YC-122C Avitruc.jpg |caption=YC-122C |type=Military transport aircraft |manufacturer=Chase |designer= Michael Stroukoff |first_flight=18 December 1947 |introduction= |retired= |status= |primary_user= |more_users= |produced= 1947–1953 |number_built=18 |developed_from= Chase CG-14 |variants= |developed_into= Hiller X-18 }}
The '''Chase XCG-18A''' and '''YC-122 Avitruc''' (known internally as the '''Chase MS.7''') 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. 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== thumb|left|The XCG-18A The USAAF's experiences with cargo gliders 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.<ref>''World Aircraft Information Files, File 891 Sheet 26.'' London: Bright Star Publishing.</ref> 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.<ref>{{cite magazine|magazine=Popular Mechanics|author=Hearst Magazines|title=Combat Glider Carries 30 Men|url=https://books.google.com/books?id=xtgDAAAAMBAJ&pg=PA154|date=April 1948|publisher=Hearst Magazines|page=154}}</ref> {{clear}}
==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. By February 1955, at least one pilot, Captain Phillip C. Gromley of the 16th Troop Carrier Squadron, 463rd Troop Carrier Wing, achieved 1,000 hours in piloting the aircraft.<ref>Simmons, G. [http://www.brightok.net/~gsimmons/mem53-59.htm "Chronological Reminders Of The Past."] {{Webarchive|url=https://web.archive.org/web/20120402085459/http://www.brightok.net/~gsimmons/mem53-59.htm |date=2012-04-02 }} ''Ardmore Air Force Base'', 2014. Retrieved: 26 January 2014.</ref> All aircraft were replaced by Fairchild C-123B Providers by July 1955. The last YC-122C assault transport was flown to Tucson, Arizona, on 30 August 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.
==Variants== thumb|right|A YC-122 in flight ;Chase MS.7 :Company designation for the XCG-14B / XCG-18A ;XCG-18A :XCG-14B re-designated ;XG-18A :revised glider version (4 built) ;YC-122 :prototype powered version, an XG-18A with Pratt & Whitney R-2000-11 engines (one built) ;YC-122A :refined version of the YC-122 (two built) ;YC-122B :YC-122A re-engined with Wright R-1820-101 engines (one converted) ;YC-122C :definitive service trials version (nine built)
==Operators== ;{{USA}} *United States Air Force **16th Troop Carrier Squadron (Assault) **316th Troop Carrier Group
==Specifications (YC-122C)== {{multiple image |total_width = 500 | image1 = Chase YG-18A 3-view line drawing.png | alt1 = 3-view line drawing of the Chase YG-18A | caption1 = 3-view line drawing of the Chase YG-18A | image2 = Chase YC-122B 3-view line drawing.png | alt2 = 3-view line drawing of the Chase YC-122B | caption2 = 3-view line drawing of the Chase YC-122B }}
{{Aircraft specs |ref=''Jane's All The World's Aircraft 1951–52''<ref name="jawa51 p214-5">Bridgman 1951, pp. 214c–215c.</ref> & ''American Military Transport Aircraft Since 1925''{{sfn|Johnson|2013|p=192}} |prime units?=imp |crew=Two pilots |capacity=30 troops ''or'' 24 stretchers ''or'' {{cvt|7500|lb|t}} cargo |length m= |length ft=61 |length in=8 |length note= |span m= |span ft=95 |span in=8 |span note= |height m= |height ft=24 |height in=8 |height note= |wing area sqm= |wing area sqft=812.8 |wing area note= |aspect ratio=11.25:1 |airfoil= |empty weight kg= |empty weight lb=19000 |empty weight note= |gross weight kg= |gross weight lb= |gross weight note= |max takeoff weight kg= |max takeoff weight lb=40000 |max takeoff weight note= |fuel capacity= |more general=
|eng1 number=2 |eng1 name=Wright R-1820-101 |eng1 type=9-cylinder air-cooled radial piston engine |eng1 kw= |eng1 hp=1425 |eng1 note= |power original=
|prop blade number= |prop name= |prop dia m= |prop dia ft= |prop dia in= |prop dia note=
|max speed kmh= |max speed mph=240 |max speed kts= |max speed note= |cruise speed kmh= |cruise speed mph=200 |cruise speed kts= |cruise speed note= |stall speed kmh= |stall speed mph=75 |stall speed kts= |stall speed note= |range km= |range miles=1000 |range nmi= |range note=with maximum cargo |combat range km= |combat range miles= |combat range nmi= |combat range note= |ferry range km= |ferry range miles= |ferry range nmi= |ferry range note= |endurance= |ceiling m= |ceiling ft=29100 |ceiling note= |g limits= |roll rate= |glide ratio= |climb rate ms= |climb rate ftmin=1340 |climb rate note= |time to altitude= |lift to drag= |wing loading kg/m2= |wing loading lb/sqft= |wing loading note= |fuel consumption kg/km= |fuel consumption lb/mi= |power/mass=
|more performance=
|avionics= }}
==See also== {{aircontent <!-- include as many lines are appropriate. additional lines/entries with carriage return. --> |related= * {{Annotated link|Chase YCG-14}} * {{Annotated link|Hiller X-18}} |similar aircraft= * {{Annotated link|Chase XCG-20}} * {{Annotated link|Fairchild C-123 Provider}} |lists= *List of military aircraft of the United States |see also= }}
==References==
===Notes=== {{Reflist}}
===Bibliography=== {{Refbegin}} * Bridgman, Leonard. ''Jane's All The World's Aircraft 1951–52.''London: Sampson Low, Marston & Co. Ltd, 1951. * {{cite book |last=Johnson |first= E. R. |date=2013 |title=American Military Transport Aircraft Since 1925 |location=Jefferson, North Carolina |publisher=McFarland & Company, Inc. |isbn=978-0-7864-6269-8}} * Taylor, Michael J. H. ''Jane's Encyclopedia of Aviation.'' London: Studio Editions, 1989. {{ISBN|0-517-69186-8}}. *''World Aircraft Information Files, File 891 Sheet 26–27.'' London: Bright Star Publishing, 1989. {{Refend}}
==External links== {{Commons category|Chase YC-122}} * [http://www.john2031.com/chase/stroukoff_avitruc.html Chase Aircraft Stroukoff Avitruc – John2031.com] * [http://www.john2031.com/chase/yc-122c_avitruc/bro1.pdf YC-122C Brochure]
{{Chase aircraft}} {{US glider aircraft}} {{USAF transports}} {{Authority control}}
C-122 Chase C-122 Avitruc Chase CG-18 Category:High-wing aircraft Category:Aircraft first flown in 1947 Category:Twin piston-engined tractor aircraft Category:Aircraft with retractable tricycle landing gear