Hispano-Suiza 24Y and 24Z
| Industry | Aerospace, Aircraft engines |
|---|---|
| Founded | 1904 |
| Headquarters | France |
| Products | Aircraft engines (including 24Y and 24Z H-24 cylinder engines) |
Hispano-Suiza 24Y and 24Z represent 24-cylinder powerplants configured in an H arrangement, engineered by Hispano-Suiza in France prior to and during the Second World War.
24Y type 82
In 1936, the French Air Ministry commissioned a new aircraft engine delivering approximately 2000 horsepower for use in a transatlantic flying boat initiative. Hispano-Suiza, already manufacturing the 12Y—a 1000 hp V12 primarily installed in fighter aircraft—developed the new model by expanding upon the 12Y design. Unlike rivals such as Allison with its V-3420 and Daimler-Benz's DB 606, Hispano-Suiza opted for a compact H configuration rather than pairing two V12 engines side-by-side. This design integrated two vertically oriented Flat-12 engines, each equipped with an individual crankshaft, connected via a shared gearbox. Key elements including superchargers, cooling apparatus, pumps, and other components were directly adapted from the 12Y. Although a prototype underwent testing, further development was halted due to wartime demands. After World War II, the prototype was found in Poland.
24Y type 90
Conceived concurrently with the Type 82, this variant differed by powering contra-rotating propellers instead of merging output from both crankshafts into a single propeller shaft. Unfortunately, the prototype was lost during the conflict.
24Z type 95
Initiated in 1943 by Hispano-Suiza’s design team relocated to Tarbes, this iteration resembled the Type 90 but was based on the more advanced 12Z engine, which incorporated four valves per cylinder among other enhancements. Theoretical output reached up to 3600 hp, targeting application in the SNCASE SE.580 fighter aircraft. Attempts to adapt this engine for postwar civilian markets were unsuccessful. A surviving prototype is exhibited at the Musée de l'air et de l'espace.