The jet had a successful maiden flight last month. Mitsubishi said today it had identified several issues needing to be addressed and decided to revise the jet's development schedule.
Industrial conglomerate Mitsubishi aims to reclaim Japan's one-time status as an aviation power some 70 years after Japan suspended making planes following its defeat in World War II.
The project is the successor to a failed attempt in the 1960s to break into the international market with the 64-seat turboprop YS-11.