Soekarno â€“ Hatta International Airport is the primary airport serving the Jakarta metropolitan area on the island of Java in Indonesia operated by PT. Angkasa Pura II. To perform scheduled flights, an airline must have flight approval for the domestic and international operations. However, the actual flight schedule can be changed from the issued flight approval if the hourly capacity still can accommodate the flights. In this case, the airport hourly capacity calculation only considers the runway hourly capacity, while the apron and terminal capacity are only based on the available resources in general. A problem can arise when the flight changes, but the apron cannot accommodate the new flight schedule or aircraft type. This study will analyse the difference between flight approval and daily flight schedules, then correlate this phenomenon with the apron capacity per hour. There are several studies about airport capacity with the point of view of runway, apron, and the combination of all airport aspects. This study will focus on calculating apron capacity per hour by considering the aircraft type and size along with specific user restrictions. For this conducted research, the user is classified into several flight categories depending on the flight operatorâ€™s origin and type of flight. For local operators, the flights are divided by the type of service: full-service, medium service, and low-cost. For foreign operators, the category is based on the origin country of the airlines. The flights are also classified based on the type of flight: domestic, international, cargo, and private flight. Then, a simulation model is developed in this research to estimate apron capacity hourly. This model uses dynamic data as the input variables in distribution form of interarrival time and ground time of aircraft. The distribution of interarrival time and ground time is searched using Distribution Fitter app in Matlab, then the best-fitted distribution is defined by using goodness-of-fit one-sample Kolmogorov-Smirnov test. The simulation model is established using Simulink on Matlab. The simulation result shows that all aprons can serve a maximum of 27 aircraft and a total of 372 aircraft in a day. Then this result is compared to historical data to discover the model behavior. It is discovered that the simulation cannot capture high fluctuation in the number of aircraft arrival per hour, which results in a lower number of served aircraft than the historical data.