Abstract: A system of wireless communication between a ground intercom of an aircraft and external systems comprises: a) an access door of a ground intercom access compartment of the aircraft, the door configured to be fixed to the compartment; b) a wireless ground intercom communications processing circuitry comprised in the door; and c) antenna(s) comprised in the door. The compartment comprises a ground intercom access panel, which comprises socket(s). The processing circuitry is operatively connectable to the ground intercom of the aircraft, via the panel, and to the antenna(s Plug(s) are connected to the processing circuitry, and are configured for plugging into the socket(s). This thereby enables retrofit of the system on an existing aircraft, by means of plugging the plug(s) into socket(s) of an existing ground intercom access panel of the aircraft. The system selectively provides wireless communication between the aircraft's ground intercom and the external system(s).