Practical real-time fluid dynamic air brake models for long heavy haul trains have not been reported in open literature. Based on a previous work titled “Railway Air Brake Model and Parallel Computing Scheme” in the same journal, this paper proposed upgrades to the previous model and achieved the real-time feature. The real-time contributing factors included a new brake cylinder model, a new scheme for updating characteristics, and the application of parallel computing. Results show that, for a 150-wagon train emergency brake simulation, the computing speed was improved from 5.26 times slower than real-time to 8.6 times faster than real-time. The three contributions improved the computing speed by 8.8, 1.8, and 2.9 times faster than the baseline models, respectively.