The long-range twin-engine Mitsubishi G4M torpedo bomber had a relatively small bomb load of 1000 kg but a long flight range of about 6000 km.
Because of the Washington Naval Agreement, Japan was far behind in fleet construction. Therefore, to guard against potential enemy warships, the 10-Shi specification was created, calling for a long-range, twin-engine torpedo bomber.
The power plant consisted of two engines with 1530 horsepower. The plane was the first Japanese plane in history to use retractable landing gear.
Needing to make weight cutbacks to construct a high-speed and long-range bomber, the designers abandoned fuel tank protection, assuming that the G4M1 would be able to flee from enemy fighters. The designers’ hopes did not materialize: the wings (where the fuel tanks were located) easily caught fire, and at the war’s start fighters which could catch up to the bombers without much difficulty were already in the air.
All in all, 1170 G4M1s were constructed.