Cornelius XFG-1

{{Infobox aircraft begin

| name=XFG-1

| image= File:Cornelius XFG-1.jpg

| caption=

}}{{Infobox aircraft type

| type=Fuel tanker glider

| national origin= United States

| manufacturer=Cornelius Aircraft Co.

| designer=George Cornelius

| first flight=1944

| introduced=

| retired=

| status=

| primary user= United States Army Air Force

| number built=2

| developed from=

| variants with their own articles=

| developed into=

}}

The Cornelius XFG-1 was an American military fuel transporting towed glider, without a tailplane and with a forward-swept wing. Two were built but development ended in 1945.

Design and development

The Cornelius XFG-1, developed under the project designation MX-416{{cite web |last1=Parsch|first1=Andreas |last2=Culy |first2=George |title=MX-1 to MX-499 Listing |url=http://www.designation-systems.net/usmilav/mx/1-499.html |website=www.designation-systems.net |access-date=19 March 2018}} was an aerodynamically unusual aircraft intended for an unusual military role. George Cornelius had been experimenting with aircraft featuring differentially variable incidence since the 1920s.{{cite journal|last1=Meaden|first1=Jack|title=Letters:Cornelius Experiments|journal=Flight International|date=24–30 January 1990|volume=137|issue=4200|page=47|url=https://www.flightglobal.com/pdfarchive/view/1990/1990%20-%200181.html|access-date=19 March 2018}} His first two machines were otherwise conventional but the third, the Cornelius Mallard from 1943 was not, being without a horizontal tailplane and having low aspect ratio and strongly forward swept wings. Though very different in detail, the XFG-1 built on the Mallard experience. A 1/4 scale model of the XFG-1 was built for wind tunnel tests.{{cite journal |title=Gliding Gas tank may Refuel planes on Ocean Hops |journal=Popular Science |date=August 1946 |page=124 |url=https://books.google.com/books?id=LiEDAAAAMBAJ&pg=RA2-PA124|publisher=Bonnier Corporation |language=en}}

The FG in its designation stood for fuel glider and its role was as a fuel transport. It was to be towed behind another aircraft rather like contemporary troop carrying gliders, but its two fuselage tanks held {{cvt|677|USgal|impgal l}} of avgas.{{cite journal|title=The Rise and Demise of a Weapon, Part Four|journal=Air Enthusiast|date=June 1972|page=320}} Unlike other troop carrying gliders, e.g. Waco CG-4, the XFG-1 could be towed by modern bombers or transports at a cruise speed of {{cvt|250|mph|kn km/h}}. Proposals seem to have included a piloted tow version behind a large transport, the glider landing loaded on skids having jettisoned its wheels after takeoff; or a pilot-less version towed behind a B-29 bomber, disconnected and abandoned after fuel transfer was completed; the intent of the scheme being for the glider to act, essentially, as a giant, winged drop tank for extending the range of the towing aircraft.{{cite book|last1=Bowers|first1=Peter M.|title=Unconventional aircraft|date=1990|publisher=TAB Books|location=Blue Ridge Summit, PA|isbn=978-0-8306-8450-2|page=264|edition=2nd}}

The XFG-1 was a high-wing monoplane, its wing set far back towards its vertical stabilizer. The wing was quite high aspect ratio and of modest forward sweep. Though the earlier Cornelius aircraft had wings that had their incidence variable in the air, the incidence on the XFG-1 could only be adjusted on the ground, with two settings of 3˚ and 7˚. There was no horizontal tail. It had a simple fixed tricycle undercarriage and a conventional single seat cockpit; two examples of the type were built.{{cite book|last1=Miller|first1=Jay|title=The X-planes: X-1 to X-45.|date=2001|publisher=Midland Pub.|location=Hinckley|isbn=978-1-85780-109-5|page=207|edition=3rd}}

Operational history

Two prototypes were built (44-28059 and 44-28060) and 32 flights were made between them in 1944–45, although the first was lost to a spin, killing the pilot. On many of the flights, but not the fatal one, the pilot was Alfred Reitherman.{{cite journal |last1=Meaden |first1=Jack |title=Letters section: Mallard pilot |journal=Flight International |date=14–20 February 1990 |volume=137 |issue=4203 |page=44 |url=http://www.flightglobal.com/pdfarchive/view/1990/1990%20-%200440.html |access-date=19 March 2018}} The fuel glider concept was abandoned at the end of World War II.

Specifications (XFG-1)

{{Aircraft specs

|ref=,{{cite book|last1=Fahey|first1=James C.|title=US Army Aircraft 1908-1946|date=1946|publisher=Ships and Aircraft|location=New York|page=37}} Fighting gliders of World War II{{cite book |last1=Mrazek |first1=James E. |title=Fighting gliders of World War II |date=1977 |publisher=Hale |location=London |isbn=978-0-312-28927-0 |pages=[https://archive.org/details/fightinggliderso00mraz/page/145 145-=148] |url-access=registration |url=https://archive.org/details/fightinggliderso00mraz/page/145 }}

|prime units?=imp

|crew=0/1

|length ft=29

|length in=3

|span ft=54

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|wing area sqft=356

|aspect ratio=

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|empty weight lb=3362

|gross weight lb=8000

|max takeoff weight lb=

|fuel capacity={{cvt|677|USgal|impgal l}}

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References

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Further reading

  • {{cite book |title=Jane's all the World's Aircraft 1947 |editor1-last=Bridgman |editor1-first=Leonard |year=1947 |publisher=Sampson Low, Marston & Co |location=London |page=210c}}
  • {{cite book|last1=Stone|first1=Ralph W. Jr.|last2=Daughtridge|first2=Lee T. Jr.|title=FREE-SPINNING, LONGITUDINAL TRIM AND TUMBLING TESTS OF 1/17.8 SCALE MODELS OF THE CORNELIUS XFG-1 GLIDER|date=1945|publisher=NACA: Langley Memorial Aeronautical Laboratory|location=Hampton, Virginia, United States}}