Final part of triptych of prewar British designs terminated by WWII.
The termination of the Supermarine 316/317/318 bomber was the most significant victory of the Luftwaffe's early strategic bombing campaign.
Initial successful design for the RAF's heavy bomber programme, the Shorts Stirling was also ordered for prototype aircraft as an "insurance aircraft" in the event of problems with the Supermarine design.
The 317 was designed with a choice of 4 different engines, a massive vertical tail, Supermarine designed defensive turrets, and a novel deltoid wing - with bomb bays though the wings out to the outer engine nacelles.
Significant reworking of the design, including a new Large Spitfire-style oval wing, was sufficient to change the designation to 317 for the Hercules-engined version, and 318 for the Merlin-engined version. Work on the Merlin version was eventually halted, and the 317 prototypes put into construction.
Luftwaffe bombing destroyed the prototypes before completion, and destroyed the construction facility and design data. With no ability to continue the bomber, the Stirling was ordered into production.
If production had continued, the Stirling would have not progressed. The Merlin version would have been brought into production, and the effort expended to create the world-beating Lancaster from the disastrous Manchester would have instead been devoted to the 317/318.
The 318 is modeled as a matured design, with the aircraft depicted as an aircraft that was a actually a Lancaster bomber.