“Following the arrival of the four Maurice Farman 1913 aircraft from France, the manufacture in Japan of Kaishiki [‘math solution’] No.5 and No.6 was put under the two officers who had studied in France and purchased the aeroplanes, Lt Kenjiro Nagasawa and Lt Shigeru Sawada. The aircraft were built from the same drawings but one was constructed at the PMBRA at Tokorazawa and the other at the Artillery Arsenal in Tokyo. Both were powered by 70hp Gnome rotary engines, experimentally manufactured at the Artillery Arsenal, but they proved less reliable than [imported] 70hp Renault engines, thus ending the production of the Gnome-type after only two engines had been built.
“The two aeroplanes were a combination of designs for the Kaishiki No.3 and No.4 airframe and Maurice Farman 1913 wings. They were completed in the autumn of 1913 and entered operational service [as] ‘Type Mo 1913’ aeroplanes. Compared to the four preceding imported models, the two new [domestically-produced] aeroplanes had more powerful engines, making them faster by 2.7kt, larger fuel capacity (for a duration of four hours), and the seats were located in a longer fuselage nacelle to improve visibility for aerial reconnaissance. Within the PMBRA, the two aeroplanes were unofficially called Kaishiki Second Year Model (Second year of Taisho, i.e. 1913).”
– Japanese Aircraft, 1910-1940, by Robert C. Mikesh & Shorzoe Abe, 1990