Hiro Type 91

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 Imperial Japanese Navy in the mid-1930s. Power was in the 450 kW (600 hp) range. Its design was derived from the Napier Lion. An enlarged more powerful engine, the Hiro Type 90 600 hp water-cooled W-12 had also been developed, producing 600 hp.

Applications

 * Aichi E10A
 * Aichi E11A
 * Hiro H4H
 * Kawanishi E7K
 * Mitsubishi Ka-9