FS2004/FSX – Spitfire Mk XVI. The Mk. XVI emerged as gradual evolution from the highly-successful Mk IX, inheriting the many minor modifications introduced during its production but otherwise similar in all respects except for the engine, being the American-built Packard Merlin 266, license-built version of the Rolls-Royce Merlin 66. The difference in service tooling between the British and American engines necessitated the introduction of the new mark, but Mk. IXs and XVIs were otherwise produced on the same productions lines, depending on the availability of the engines. Tested in FS2004/FSX/FSX Acceleration. Gmax model by A.F. Scrub.