FSX Acceleration Curtiss P40K. The P-40K was the heaviest of the P-40 family. It served mainly in the Pacific theater and in China. It should have been the last model of the P-40 produced, but troubles with the P-60 program left production capacity available at the Curtiss factories, so the production of P-40s was continued despite the obvious weaknesses of the model. Gmax model by A.F. Scrub.