Fun trivia: While obviously impossible in Stormworks, radial engines always have an odd number of cylinders in each ring of cylinders. Engines with an even number of cylinders have two or four rings of cylinders. The B-29's Wright R-3350 Duplex-Cyclone had two rings of nine cylinders, for example. The engine used on the B-50 (essentially a modified B-29) was the Pratt & Whitney R-4360 Wasp Major, which had four rings of seven cylinders, totaling 28. These were also used for the propeller drive on the B-36, which also carried four General Electric J47-19 turbojets.

All that being said, this is hands-down the most aesthetically convincing radial I've seen in Stormworks so far.