[3] Beardmore-Halford-Pullinger (BHP) were initially tasked with developing an aero-engine to compete with the latest German inline six-cylinder models.

Although BHP's design was projected to produce 300 hp (224 kW) the engine's output came in below expectations.

[3] The Adriatic's cylinders were constructed in groups of three with each block being made from a single aluminum casting.

[2][4] The relatively large and intricate aluminum casting was challenging to produce which led to significant production delays.

[6] A single steel stamping formed the cooling water jacket for groups of three cylinders.

[6] It is notable that the Siddeley Puma's cylinder heads and water jackets are made of aluminum.

[2] The Adriatic was one of a series of upright water-cooled inline aircraft engines produced by Beardmore and its subsidiary companies.

[2] In addition to the 94 Adriatic engines produced by Galloway, the firm also supplied components to Siddeley-Deasy.