Chasle YC-100 Hirondelle

The Chasle YC-100 Hirondelle (Swallow) is a French single seat microlight designed in the 1980s.

Design and development
Yves Chasle worked as an Aérospatiale stress engineer and independently designed several light aircraft, starting with the Chasle YC-12 Tourbillon. His YC-100 Hirondelle is a largely wooden framed and fabric covered single-seat sports aircraft of conventional pusher layout. It has a strut braced high wing of constant chord with styrofoam ribs. The fuselage of the Hirondelle is a slender, rectangular cross-sectioned beam with the pilot's seat upon it ahead of the wing leading edge. Behind the pilot a central structure supports the wing just above head level; on its trailing edge, one of several types of small piston engine, with power outputs typically around 20 kW, drives a pusher propeller. The fin is broad and straight-tapered and the horizontal tail is attached to the fuselage underside. The Hirondelle has a short, fixed tricycle undercarriage.

Its first flight was on 1 May 1985, powered by a 18 kW König SC 430 engine, a 430 cc (26.2 cu in), air-cooled, three-cylinder radial. The second prototype, built in Brazil, had a 22 hp JPX PUL 425/503 engine, a 212 cc (12.9 cu in) air-cooled flat-twin two stroke.

The number built is uncertain; in 2009 two examples, both YC-100s, appeared on European civil registers, one in Spain and one in France.

Variants
Plans for these were available but only the YC-100 is known to have been built.
 * YC-100: As described below but could also be fitted with a 22 hp JPX PUL 425/503.
 * YC-101: As YC-100 but span increased to 9.35 m. Recommended engines were the JPX PUL 865, the 28 hp König SD 570 or the 30 hp KFM 107ER.
 * YC-110: Shorter span (8.25 m wings with NACA 23015 section and Junkers type, two part, full span auxiliary airfoil ailerons or flaperons. Recommended engines as YC-100 and also the König SD 570.
 * YC-111: Longer span (9.35 m) YC-110. Recommended engines were the König SD 570, KFM 107ER, JPX PUL 865 and also the Rotax 377 or 447, respectively 26 kW and 29.4 kW.