01/31/2009. Remarks by Johan Visschedijk: "Preliminary design of this light utility twin-prop transport aircraft, then known as the Wolfsberg Raven 257, was started by Alec Clark of the Belgian company Wolfsberg Aircraft in 1995, and detail design was done in 1997. A number of companies participated in the manufacturing of the prototype, including Letov Air in Prague, Czech Republic (wings and tail surfaces), Evektor-Aerotechnik in Kunovice (fuselage and final assembly), and GAIC of China (landing gear).

In early 1999 Wolfsberg-Evektor was formed, to manage the Raven program, while on June 1, 2000, Letov Air became a subsidiary of Wolfsberg Aircraft as Letecká Tovarna (Aircraft Factory), abbreviated to Letov. Registered as OK-RAV, the pictured aircraft flew for the first time on July 28, 2000. Only four months later, on November 21, 2000, the partnership with Evektor-Aerotechnik was terminated and development and production was transferred to Letov and the Raven had some major structural modifications.

In 2003 Letecká Tovarna was restructured and became Wolfsberg Letecká Tovarna s.r.o., and a second prototype was constructed with the designation Corvus 1, and registered as OK-WLT it was flown for the first time at Praha-Kbely on June 6, 2006.

The Raven registration OK-RAV was cancelled on September 4, 2006, it disappeared without a trace on November 22, 2007, after it departed Colesberg, South Africa."