The Airdisco Phi-Phi was a single seat

monoplane A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple planes. A monoplane has inherently the highest efficiency and lowest drag of any wing confi ...

glider Glider may refer to: Aircraft and transport Aircraft * Glider (aircraft), heavier-than-air aircraft primarily intended for unpowered flight ** Glider (sailplane), a rigid-winged glider aircraft with an undercarriage, used in the sport of glidin ...

, designed specifically for the first British gliding competition held at Itford Hill in 1922, an endurance event. It recorded one competitive flight but crashed on a second attempt.

Design

In August 1922 the ''

Daily Mail The ''Daily Mail'' is a British daily middle-market tabloid newspaper and news websitePeter Wilb"Paul Dacre of the Daily Mail: The man who hates liberal Britain", ''New Statesman'', 19 December 2013 (online version: 2 January 2014) publish ...

'' newspaper offered a £1,000 prize for the longest duration flight by an unpowered, heavier than air aircraft. The competition was to be organized by the Royal Aero Club, who chose the site (Itford Hill, on the

Sussex Sussex (), from the Old English (), is a historic county in South East England that was formerly an independent medieval Anglo-Saxon kingdom. It is bounded to the west by Hampshire, north by Surrey, northeast by Kent, south by the English ...

South Downs The South Downs are a range of chalk hills that extends for about across the south-eastern coastal counties of England from the Itchen valley of Hampshire in the west to Beachy Head, in the Eastbourne Downland Estate, East Sussex, in the east. ...

near

Lewes Lewes () is the county town of East Sussex, England. It is the police and judicial centre for all of Sussex and is home to Sussex Police, East Sussex Fire & Rescue Service, Lewes Crown Court and HMP Lewes. The civil parish is the centre of ...

) and the date (16–21 October). This gave competitors six weeks to design, build and transport their entries. 13 arrived in time and one of these was the

Airdisco The Aircraft Disposal Company (ADC) or Airdisco, was a British firm established in March 1920 to take advantage of the large number of World War I-surplus military aircraft on the market.Gunston 2005, p.7. The company changed name in 1925 to ADC ...

Phi-Phi, competition number 27. The Phi-Phi was an all wood parasol

. Its wing section was thick enough to allow for semi-

cantilever A cantilever is a rigid structural element that extends horizontally and is supported at only one end. Typically it extends from a flat vertical surface such as a wall, to which it must be firmly attached. Like other structural elements, a canti ...

construction, supported centrally by two pairs of

cabane struts In aeronautics, bracing comprises additional structural members which stiffen the functional airframe to give it rigidity and strength under load. Bracing may be applied both internally and externally, and may take the form of strut, which act in c ...

and two steeply rising lift struts from the lower

fuselage The fuselage (; from the French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraft t ...

longeron In engineering, a longeron and stringer is the load-bearing component of a framework. The term is commonly used in connection with aircraft fuselages and automobile chassis. Longerons are used in conjunction with stringers to form structural ...

s, though there were a pair of drag wires from nose to wing tip. The wing plan was unusual compared with the straight edges of most of its competitors, with a gently curving

leading edge The leading edge of an airfoil surface such as a wing is its foremost edge and is therefore the part which first meets the oncoming air.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 305. Aviation Supplies & Academics, ...

, elliptical tips and straight trailing edge. It had the highest aspect ratio (13.6) of all the Itford gliders. The tip-mounted ailerons were horn balanced, again unusual. The Phi-Phi had a rectangular cross-section fuselage, with sides that curved in at the nose and, more gently, towards the tail. In plan the sides were straight edged, forming an elongated rhomb. A low aspect ratio, rectangular,

all-moving tailplane A stabilator is a fully movable aircraft horizontal stabilizer. It serves the usual functions of longitudinal stability, control and stick force requirements otherwise performed by the separate parts of a conventional horizontal stabilizer and el ...

was hinged on the extreme rear fuselage. The

fin A fin is a thin component or appendage attached to a larger body or structure. Fins typically function as foils that produce lift or thrust, or provide the ability to steer or stabilize motion while traveling in water, air, or other fluids. Fin ...

and

rudder A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, aircraft, or other vehicle that moves through a fluid medium (generally aircraft, air or watercraft, water). On an aircraft the rudder is used primarily to ...

formed a tilted, cropped parallelogram with a hinge line above that of the

elevator An elevator or lift is a wire rope, cable-assisted, hydraulic cylinder-assisted, or roller-track assisted machine that vertically transports people or freight between floors, levels, or deck (building), decks of a building, watercraft, ...

. The cockpit was immediately under the leading edge, well behind the nose. Originally the Phi-Phi had a pair of small main wheels rigidly attached to the lower fuselage directly below the cockpit and aided by a sprung, articulated

tailskid Conventional landing gear, or tailwheel-type landing gear, is an aircraft undercarriage consisting of two main wheels forward of the center of gravity and a small wheel or skid to support the tail.Crane, Dale: ''Dictionary of Aeronautical Terms ...

. The wheels were replaced at Itford by a pair of skids and then by skids with small wheels attached to them.

Operational history

The Phi-Phi, flown by Rex Stocken, did not fly until Friday 20 October, the penultimate day of the competition. After a few brief trials and some adjustment to the undercarriage, Stocken made a competition flight that lasted 3 min 18 s. Observers noted that whilst the Phi-Phi lifted off easily enough, like other British gliders present it lacked the rudder authority to hold it into the wind. The following afternoon Stocken attempted another flight but crashed. At the end of the competition he was awarded the Col. Bristow Cup.

Specifications

References

--> {{cite magazine , title= The British Gliding Competition, magazine= Flight, issue=26 October 1922 , pages=626, 629 , url= http://www.flightglobal.com/pdfarchive/view/1922/1922%20-%20062.html 1920s British aircraft Glider aircraft Aircraft first flown in 1922 Parasol-wing aircraft