Note: This item is currently in storage.The Salmson Z-9 engine, rated at 280 hp, was quite unique. Although it was a radial engine, it was cooled by water. The Z-9 was installed in the Salmson 2A.2 airplane, which arrived on the Front early in 1918. The U.S. Air Service purchased 705 Salmson 2A.2s