Fifth generation (5G) non-standalone (NSA) radio access system employing virtual fourth generation (4G) master connection to enable dual system data connectivity. The 5G NSA radio access system employs a virtual 4G radio access node (RAN) to provide a logical master data connection to a user mobile communications device, and a 5G RAN to provide an additional, secondary high-speed data plane between the user mobile communications device to a core network. The virtual 4G RAN does not provide an actual 4G radio connection over-the-air to the user mobile communications device. Instead, the signaling transported between the user mobile communications device and the virtual 4G RAN is provided over a non-radio connection, such as an internet protocol (IP) connection. In this manner, the deployment of the 5G NSA radio access system employing the virtual 4G RAN can be achieved without updating existing 4G RANs and/or without deploying a new 4G RAN infrastructure.