The SIPA S.251 Antilope was a low-wing

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 ...

, seating four or five and powered by a single

turboprop engine A turboprop is a turbine engine that drives an aircraft propeller. A turboprop consists of an intake, reduction gearbox, compressor, combustor, turbine, and a propelling nozzle. Air enters the intake and is compressed by the compressor. Fuel ...

, developed in France in the early 1960s. It set a number of class records but was not put into production.

Design and development

The Antilope was one of the first turboprop powered light aircraft. Apart from its engine, it was a conventional all-metal low-wing machine. The cantilever wing was built around two spars and was a semi-monocoque structure, carrying unslotted ailerons and electrically powered, single slot

Fowler flaps A flap is a high-lift device used to reduce the stalling speed of an aircraft wing at a given weight. Flaps are usually mounted on the wing trailing edges of a fixed-wing aircraft. Flaps are used to reduce the take-off distance and the landing ...

. The fuselage was also of semi-monocoque construction. The tail unit included a variable incidence tailplane and a rudder with a

trim tab Trim tabs are small surfaces connected to the trailing edge of a larger control surface on a boat or aircraft, used to control the trim of the controls, i.e. to counteract hydro- or aerodynamic forces and stabilise the boat or aircraft in a pa ...

. It had an electrically actuated tricycle undercarriage, the main wheels retracting inwards into the wings. The cabin had seats for four or five, two at the front and a bench seat behind. In a proposed air ambulance configuration, the Antilope would have carried two stretchers and a medic. Access to the cabin was via a large rear hinged door on the starboard side. The Antilope was powered by a 665 hp (495 kW)

Turbomeca Astazou X The Turbomeca Astazou is a highly successful series of turboprop and turboshaft engines, first run in 1957. The original version weighed and developed at 40,000 rpm. It was admitted for aviation service on May 29, 1961, after a 150-hour test ru ...

driving a 3-bladed propeller, on a long spinner, well ahead of the surrounding air intake. It first flew on 7 November 1962 and gained certification in April 1964. That autumn, P. Bonneau set six international Class C1c (1000 – 1750 kg) records with it, achieving for example a speed of 432.9 km/h (267 mph) over a 3 km course and reaching an altitude of 10,420 m (34,186 ft). Early in 1965 it flew with a four-bladed propeller and improved on one of its own records. A three-blade propeller was re-installed and the aircraft was exhibited at the 1965

Paris Air Show The Paris Air Show (french: Salon international de l'aéronautique et de l'espace de Paris-Le Bourget, Salon du Bourget) is a trade fair and air show held in odd years at Paris–Le Bourget Airport in north Paris, France. Organized by the French ...

wearing registration ''F-BJSS''. By mid 1966 development had been completed without a decision to commence production. The production version would have been known as the SIPA S.2510 Antilope but none were built; the prototype (''F-WJSS'') carried the designation S.251 on its fin. The sole Antilope is undergoing restoration in a private museum, owned by the ''Association Antilope'', at Montpelier-Mediterranee Airport, in southern France.

Design and development

Specifications (S.2510)

References

Further reading