The Druine D.31 Turbulent is a French single-seat ultralight

Homebuilt aircraft Homebuilt aircraft, also known as amateur-built aircraft or kit planes, are constructed by persons for whom this is not a professional activity. These aircraft may be constructed from "scratch", from plans, or from assembly kits.Armstrong, Kenn ...

Development

The D.31 Turbulent was designed to be amateur-built and is a single-seat ultra-light aircraft with cantilever low-wing and fixed tailwheel landing gear. Designed to be powered by a 30 hp (1200cc)

Volkswagen Volkswagen (),English: , . abbreviated as VW (), is a German motor vehicle manufacturer headquartered in Wolfsburg, Lower Saxony, Germany. Founded in 1937 by the German Labour Front under the Nazi Party and revived into a global brand post-W ...

or similar engine. The fuselage and wings use wood construction with fabric covering. Rollason Aircraft & Engines Limited produced 26 factory-built D.31 aircraft in the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...

and three D.31A models with strengthened

wing spar In a fixed-wing aircraft, the spar is often the main structural member of the wing, running spanwise at right angles (or thereabouts depending on wing sweep) to the fuselage. The spar carries flight loads and the weight of the wings while on t ...

in order to get a full British certificate of Airworthiness.Jackson Vol 3 1988, pp. 546–548. Five Turbulents are operated by the Tiger Club in 2019.Turb Team Turbulents
/ref> The rights to plans for the design are held by the UK

Light Aircraft Association The Light Aircraft Association (LAA) is the representative body in the United Kingdom for amateur aircraft construction, and recreational and sport flying. It oversees the construction and maintenance of homebuilt aircraft, under an approval from t ...

.Bayerl, Robby; Martin Berkemeier; et al: ''World Directory of Leisure Aviation 2011–12'', page 107. WDLA UK, Lancaster UK, 2011. ISSN 1368-485XTacke, Willi; Marino Boric; et al: ''World Directory of Light Aviation 2015–16'', page 113. Flying Pages Europe SARL, 2015.

Operational history

The Tiger Club Turbulent displays have been a highlight of the UK air display scene since 1959 and, by remaining in sight of the crowd at all times, their displays are often regarded as the most rivetting. Reviewers Roy Beisswenger and Marino Boric described the design in a 2015 review, saying, "the controls are wonderfully light, and although not aerobatic, the aircraft has been used by the Tiger Club Display Team for formation flying displays in the UK, since 1959. On 31 August 2019 the Tiger club celebrated 60 years of operating the Turbulent. In 1960, Rollason Turbulent G-APNZ was flown by

Prince Philip, Duke of Edinburgh Prince Philip, Duke of Edinburgh (born Prince Philip of Greece and Denmark, later Philip Mountbatten; 10 June 1921 – 9 April 2021) was the husband of Queen Elizabeth II. As such, he served as the consort of the British monarch from E ...

, making the Turbulent the first and only single-seat aircraft to have been flown by a member of the royal family. In the same year, the same aircraft won the King's Cup air race, flown by John Severne. G-APNZ is subject to a restoration at

Derby Airfield Derby Airfield is a small privately owned grass airfield situated between the Derbyshire villages of Egginton and Hilton, in the East Midlands of England. The airfield is 7 miles southwest of Derby, and 11 miles northeast of Tatenhill Airfiel ...

Variants

;D.3 :Original design and prototypes ;D.30: powered by Ava 4A-00 ;D.31 :Standard home-built and factory built variant. Initially built by Rollason Aircraft & Engines with 1200cc VW engine but standardized on the 1600cc Ardem 4CO2 modified VW engine. The Tiger Club have modified their aircraft to use Leburg Electronic Ignition. ;D.31A :Factory & homebuilt aircraft incorporating factory designed (by Rollason Aircraft & Engines) strengthened main spar to allow C of A certification. Top speed = 115 Knots. Max weight = 317 kg ;D.32: powered by Sarolea Epervier ;D.35: powered by Porsche ;D.36: powered by JAP J-99, G-APOL but later re-engined to D.31 standard

Specifications D.31

References

Notes

Bibliography

* A.J.Jackson, ''British Civil Aircraft 1919–1972 Volume 2'', 2nd Edition (reprint) 1988 (for homebuilt Druine Turbulents), Putnam & Company, London, 1974, * A.J.Jackson, ''British Civil Aircraft 1919–1972 Volume 3'', 2nd Edition (reprint) 1988 (for Rollason Turbulents), Putnam & Company, London, 1974, * L.Benjamin, ''Tiger Club – A Tribute, Volume 1, 1957–1966'', Cirrus Associates, 1988,

External links

Plans from LAA.Official website
{{Druine aircraft 1950s French sport aircraft

Turbulent In fluid dynamics, turbulence or turbulent flow is fluid motion characterized by chaotic changes in pressure and flow velocity. It is in contrast to a laminar flow, which occurs when a fluid flows in parallel layers, with no disruption between ...

Homebuilt aircraft Single-engined tractor aircraft Low-wing aircraft Aircraft first flown in 1951