The prototype of the Robin HR100 was the prototype DR253 Regent which was rebuilt with metal wings and powered by a 180hp (134kW) Lycoming O-360 engine. It first flew on 3 April 1969 as the Robin HR100/180. The HR100 is a low-wing cantilever monoplane with a conventional cantilever tail unit and a fixed tricycle landing gear. A number of different variants were produced in the 1970s. From 1972 a high-powered improved version was produced as the HR100/285 with a 285hp (213kW) Continental Tiara 6-285B engine and retractable landing gear and airframe modifications.
A two-seat trainer version was developed as the HR200, and a modified version with a lighter airframe and new fin and rudder was developed as the R1180 Aiglon in 1977.