Abstract
This article presents the results of building a model for calculating the operating cycle and calculating the engine performance parameters of the 7-2D42 diesel-generator when the submarine is operating in the schorkel. The constructed model is provided with reliability, the calculation results show that when the submarine switches from surface to schorkel mode, the engine power decreases by almost 12%, to maintain the original power, it is necessary to add 13.5% of fuel, and the engine efficiency decreases by more than 11%.