User:Buster40004/Sandbox/Projects/Hiro Type 90

The Hiro Type 90 was a twelve cylinder W-type engine with a bore of 135 mm. and a stroke of 160 mm. for a capacity of 27.5 litres. It appeared first in 1931 under the designation of Type 91, and had a rated power of 600 h.p. and a maximum power output of 750 h.p. The engine was installed in flying boats, sea reconnaissance aircraft with a crew of three, and in shipborne bombers.

Since in the course of further development sufficiently powered radial engines were produced, the production of liquid cooled in-line types gradually subsided in favor of the twin-row air-cooled radial.