An unusual cylinder layout: a multi-row radial engine, where inline cylinder banks are shared between rows. Many of these engines are liquid-cooled, which is otherwise rare and difficult to achieve for the usual radial engine, with staggered banks.

Many of these engines are liquid-cooled, which is rare and difficult to achieve satisfactorily for radial engine. Air-cooled multi-bank engines, such as the Armstrong-Siddeley Hyena and Deerhound had difficulties cooling the rear cylinders of each bank.

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