Scintex Rubis

The Scintex ML 250 Rubis was a French civil utility aircraft of the 1960s.

Scintex Rubis
Scintex Rubis at Guyancourt airfield, Paris, in 1965
Role	General aviation aircraft
National origin	France
Manufacturer	Scintex-Aviation
First flight	3 June 1962
Introduction	1964
Primary user	Private owners
Number built	8
Developed from	ML 145

Design and development

Scintex Aviation had manufactured the two-seat Emeraude from the late 1950s. In 1960 the firm designed the ML 145 four-seat low-wing cabin monoplane, powered by a 145 h.p. Continental O-300-B engine, the single example of which first flew on 25 May 1961.^[1]

Scintex Rubis at Toussus-le-noble airfield in 1967

Scintex developed the ML 250 with a larger five-seat cabin and fitted with a 250 hp (186 kW) Lycoming O-540 engine. This first flew on 3 June 1962.^[2] The aircraft was of a graceful design, using an all-wood construction, having a semi-monocoque plywood-covered fuselage and cantilever tapered low wing. The tail fin was swept and the aircraft, unusually, was fitted with a fully retractable tailwheel undercarriage.

Production and service

Eight production examples of the ML 250 Rubis were completed by Scintex during 1964-1965. Whilst the type had an advanced specification, it suffered from competition from contemporary all-metal aircraft types such as the Piper Comanche. The Rubis has remained in service with French private pilots and four were airworthy in 2005.^[3] Two of these, including the aircraft pictured right (F-BJMD) were still active on the French civil aircraft register in 2015.^[4]

Specifications

Data from Jane's All The World's Aircraft 1965–66^[5]

General characteristics

• Crew: 1
• Capacity: 3–4 passengers
• Length: 7.75 m (25 ft 5 in)
• Wingspan: 10.25 m (33 ft 8 in)
• Height: 1.90 m (6 ft 3 in)
• Wing area: 14.78 m² (159.1 sq ft)
• Aspect ratio: 7:1
• Airfoil: root: NACA 23015 tip: NACA 23009
• Empty weight: 800 kg (1,764 lb)
• Max takeoff weight: 1,475 kg (3,252 lb)
• Fuel capacity: 52 L (14 US gal; 11 imp gal)
• Powerplant: 1 × Lycoming O-540-A1D5 air-cooled flat-six engine, 190 kW (250 hp)

Performance

• Maximum speed: 315 km/h (196 mph, 170 kn) at sea level
• Cruise speed: 270 km/h (170 mph, 150 kn) (econ cruise)
• Stall speed: 98 km/h (61 mph, 53 kn)
• Never exceed speed: 348 km/h (216 mph, 188 kn)
• Range: 1,550 km (960 mi, 840 nmi) at 270 km/h (170 mph; 150 kn)
• Service ceiling: 6,500 m (21,300 ft)
• Rate of climb: 6.48 m/s (1,275 ft/min)
• Takeoff distance to 15 m (50 ft): 255 m (837 ft)
• Landing distance from 15 m (50 ft): 345 m (1,132 ft)