FS2004/FSX – North American Aviation P-51H Mustang. The ultimate version of the Mustang was the P-51H, which was the fastest Mustang variant to see service and one of the fastest (if not the fastest) piston-engined fighters to enter production during the Second World War. However, it was destined never to see any combat, having entered service too late to participate in the final action against Japan. Gmax model by A.F. Scrub.