The HM.381 and HM.385 are both variants of the stock HM.380, itself a two-seat version of the single-seat HM.360. The HM.381 has detail improvements over the original HM.380 while the HM.385 has a substantially different fuselage, struts and control arrangement to allow side doors, reverse tricycle landing gear and larger wings (9.0 m span front wing). All of the HM.360/380 series were specifically designed for amateur construction and plans are available for free download with the Mignet family's consent at pouguide.org. Here is a detail from the HM.385 drawings: