The Rubik R-25 Mokány, in and sometimes known as the R-25 Standard (class), is a Hungarian single seat Standard Class glider of all-metal construction, first flown in 1960. It was one of a series of similar aircraft designed by

Ernő Rubik Ernő Rubik (; born 13 July 1944) is a Hungarian architect and inventor, widely known for creating the Rubik's Cube (1974), Rubik's Magic, and Rubik's Snake. While Rubik became famous for inventing the Rubik's Cube and his other puzzles, m ...

. Only one was built.

Design and development

In 1957 a team led by Ernő Rubik designed an all-metal glider, the R-23 Gébics, with a pod and boom

fuselage The fuselage (; from the French language, French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds Aircrew, crew, passengers, or cargo. In single-engine aircraft, it will usually contain an Aircraft engine, engine as wel ...

V-tail The V-tail or ''vee-tail'' (sometimes called a butterfly tail or Rudlicki's V-tailGudmundsson S. (2013). "General Aviation Aircraft Design: Applied Methods and Procedures" (Reprint). Butterworth-Heinemann. p. 489. , 9780123973290) of an aircraf ...

mounted fan airbrakes and corrugated wing skinning. These features were carried forward into a series of gliders that included the R-25 Mokány. This was designed to compete as a Standard Class glider, with a span increased to 15 m (49 ft 5½ in), and introduced a laminar flow NACA 64 series wing profile. Its straight tapered,

high High may refer to: Science and technology * Height * High (atmospheric), a high-pressure area * High (computability), a quality of a Turing degree, in computability theory * High (tectonics), in geology an area where relative tectonic uplift t ...

cantilever A cantilever is a rigid structural element that extends horizontally and is unsupported at 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 cantilev ...

wing has forward sweep on the

trailing edge The trailing edge of an aerodynamic surface such as a wing is its rear edge, where the airflow separated by the leading edge meets.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 521. Aviation Supplies & Academics, 1997. ...

alone. It is built around a single spar with a D-shaped

torsion box A torsion box consists of two thin layers of material (skins) on either side of a lightweight core, usually a grid of beams. It is designed to resist torsion under an applied load. A hollow core door is probably the most common example of a torsio ...

formed by the corrugated leading section, the ridges running chordwise. The wing is fabric covered aft of the spar, apart from an outer, metal skinned area carrying

Frise aileron An aileron (French for "little wing" or "fin") is a hinged flight control surface usually forming part of the trailing edge of each wing of a fixed-wing aircraft. Ailerons are used in pairs to control the aircraft in Flight dynamics, roll (or ...

s. The all moving V-tail, with 90° separation and fitted with anti-balance tabs, has similar construction and plan as the wings. The metal skinned fuselage of the Mokány has a circular cross section from the tail forwards to a point a little behind the wing

where it develops into a deep ellipse, though maintaining the horizontal upper line forward to the leading edge. Beyond this, the

cockpit A cockpit or flight deck is the area, on the front part of an aircraft, spacecraft, or submersible, from which a pilot controls the vehicle. The cockpit of an aircraft contains flight instruments on an instrument panel, and the controls th ...

is covered by a single piece blown

canopy Canopy may refer to: Plants * Canopy (biology), aboveground portion of plant community or crop (including forests) * Canopy (grape), aboveground portion of grapes Religion and ceremonies * Baldachin or canopy of state, typically placed over an a ...

; the nose is sharply pointed. There is a fixed, partially enclosed and rubber sprung monowheel undercarriage, fitted with a brake and assisted by a small tail skid. Instead of the more usual wing mounted airbrakes, the Mokány has fuselage mounted brakes which open through 90° in fan fashion, with one on either side below the wings at about 25% chord. The Mokány is fully aerobatic and equipped for cloud flying.

Aircraft on display

The sole Mokány, ''HA-4300'', is on display in the Transport Museum of Budapest.

Specifications (R-25 Mokány)

Notes

References

* * * * {{DEFAULTSORT:Rubik R-25 Mokany 1960s Hungarian sailplanes Rubik aircraft Aircraft first flown in 1960 High-wing aircraft V-tail aircraft