In Apr-1990 the registration D-KASS was reserved for it as an ASH-25E which is the version with a 24hp Rotax 275 sustainer engine. In 1991 only the fuselage was completed. It was then waiting for the installation of a different engine. This became a self-launching 60hp Mid-West AE-50R engine and with this its designation changed to ASH-25M. In Sep-1995 a permit to fly was issued, and it continued to fly on the permit, never being fully registered. In Mar-2005 it was registered as HB-2351. It has "ASH-25ES" on it, which is not official, probably meaning "ASH-25E Special".

In Apr-1990 the registration D-KASS was reserved for it as an ASH-25E which is the version with a 24hp Rotax 275 sustainer engine. In 1991 only the fuselage was completed. It was then waiting for the installation of a different engine. This became a self-launching 60hp Mid-West AE-50R engine and with this its designation changed to ASH-25M. In Sep-1995 a permit to fly was issued, and it continued to fly on the permit, never being fully registered. In Mar-2005 it was registered as HB-2351. It has "ASH-25ES" on it, which is not official, probably meaning "ASH-25E Special".