Yves Chasle worked as an Aérospatiale stress engineer and independently designed several light aircraft, starting with the Chasle YC-12 Tourbillon. Beginning in 1973 he designed the LMC-1 Sprintair, an all-metal, side-by-side two-seater. The first prototype was built by about twenty members of the Léon-Morane Club, hence the model initials. Most club members were SOCATA employees, based in Tarbes.^[1]

The Sprintair has a low, cantilever, unswept, constant-chord wing, mounted with 4° of dihedral and with square tips which have slightly rounded leading edges. Structurally, the wing is a torsion box with a single main spar at 30% chord and a lighter rear auxiliary spar. Almost the whole trailing edge is occupied by a control surface, the outer parts hinged as ailerons and the inner halves as three position flaps.^[1]

The fuselage is a metal semi-monocoque with a 75 kW (100 hp) Rolls-Royce Continental O-200-A air-cooled flat four aircraft engine in the nose, driving a two-blade propeller. The two seats are over the wing under a one-piece, forward-hinged canopy which extends ahead of the leading edge. There is a fixed rear transparency that drops down to the fuselage. At the rear, the tall vertical tail is straight-edged with sweep on both fin and rudder; overall sweep is 30°. The tailplane is mounted on top of the extreme rear fuselage and, together with the elevator, is rectangular apart from a projecting, cockpit-adjustable trim tab. Both the tailplane angle of incidence and a rudder trim tab are adjustable on the ground.^[1]

The Sprintair has fixed tricycle landing gear with main wheels on faired legs mounted on the lower fuselage and an unfaired, telescopic, sprung, steerable nosewheel.^[1]

The Léon-Morane built first prototype was first flown on 18 June 1975^[1] and remained there until written off at Tarbes in 1984. At least two more, possibly three, were completed from plans provided by Chasle; one of them was still active at Toulouse in 2008.^[2]

Data from Jane's All the World's Aircraft 1976-1977^[1]

General characteristics

• Crew: One pilot
• Capacity: One passenger
• Length: 6.45 m (21 ft 2 in)
• Wingspan: 8.60 m (28 ft 3 in)
• Wing area: 10.00 m² (107.6 sq ft)
• Aspect ratio: 7.5
• Airfoil: NACA 63A218
• Empty weight: 450 kg (992 lb)
• Max takeoff weight: 700 kg (1,543 lb)
• Fuel capacity: 105 L (23 imp gal; 28 US gal), mounted in wing root tanks
• Powerplant: 1 × Rolls-Royce Continental O-200-A air-cooled flat four, 75 kW (100 hp)
• Propellers: 2-bladed McCauley, 1.80 m (5 ft 11 in) diameter metal, fixed pitch

Performance

• Maximum speed: 215 km/h (134 mph, 116 kn) at sea level
• Cruise speed: 190 km/h (120 mph, 100 kn) maximum
• Stall speed: 80 km/h (50 mph, 43 kn) flaps down
• g limits: +9/-4.5
• Take-off run: 230 m (755 ft)