Air traffic management is a critical component of aviation, aiming to balance safety, capacity and demand within controlled airspace. This research analyses Iran's domestic air transport network (2018-2021) by developing annual Origin-Destination (OD) impedance matrices based on flight frequency. The methodology quantifies network connectivity, revealing a highly centralized structure dominated by core corridors like Tehran-Mashhad, which carried over 10,500 flights in 2019. The COVID-19 pandemic caused a severe disruption in 2020, with traffic on major routes falling by nearly half, followed by a partial recovery in 2021. Analysis shows core hubs rebounded faster than peripheral airports, widening accessibility gaps. Through origin-destination matrix processing, the system identifies high density air routes and analyses historical trends in airspace utilization. The impedance matrix, validated against data (R²=0.87), successfully maps the intense service on hub links and the high impedance of sparse peripheral routes. Then an interactive Web GIS platform was implemented for spatiotemporal analysis of air traffic density.