The Hiro H3H1 or Navy Type 90-1 Flying boat was a Japanese flying boat bomber built in 1931. It was the first large all-metal aircraft built in Japan...

The Hiro H4H (or Hiro Navy Type 91 Flying Boat) was a 1930s Japanese bomber or reconnaissance monoplane flying boat designed and built by the Hiro Naval...

The Hiro Type 91, (full designation Hiro Type 91 520 hp water-cooled W-12), was a 12-cylinder, water-cooled, W engine developed for aircraft use by the...

II Hiro H4H - flying boat Prototypes and experimental aircraft: Hiro R-3 - flying boat, 1 example built Hiro H3H1 - flying boat, 1 example built Hiro H10H...

The Hiro G2H (or Hiro Navy Type 95 Twin-engined Land-based Attacker) was a 1930s Japanese bomber or reconnaissance monoplane designed and built by the...

Navy Hiro G2H land-based bomber in 1933. The Type 94 engine was the eighteen-cylinder version of the Hiro Type 90 600 hp water-cooled W-12/Hiro Type 91...

The Hiro H1H (or Navy Type 15) was a 1920s Japanese bomber or reconnaissance biplane flying boat developed from the Felixstowe F.5 by the Hiro Naval Arsenal...

The Hiro Type 14 engine, (full designation Hiro Type 14 500 hp water-cooled W-12), was a water-cooled twelve-cylinder W engine built by the Hiro Naval...

The Hiro H2H, or "Navy Type 89 Flying boat" (Japanese: "八九式飛行艇"), was a Japanese patrol flying boat of the 1930s. Designed and built by the Hiro Naval...

rearwards for storage aboard aircraft carriers. It was powered by a single Hiro Type 91 W engine rated at 450 kW (600 hp). Testing proved that the aircraft...