Aeroplane mode disables the Wifi (or WLan), bluetooth and Telephony (2G/3G etc) signals. This can be seen from system log. Also This wikipedia article says same thing about airplane mode or Aeroplane mode -
When the "airplane mode" is activated, it disables all voice and text telephony and other signal-transmitting technologies such as Wi-Fi and Bluetooth.
And this Gnome Help article says, more clearly
Using Airplane Mode will completely turn off all wireless connections, including WiFi, 3G and Bluetooth connections.
When it's disabled I find entry in systemlog like these
Sep 10 16:14:13 anwar-pc NetworkManager[957]: <info> [1473502453.7404] manager: WiFi now disabled by radio killswitch
Sep 10 16:14:13 anwar-pc NetworkManager[957]: <info> [1473502453.7616] device (20:54:76:75:5B:C6): state change: disconnected -> unmanaged (reason 'removed') [30 10 36]
Sep 10 16:14:13 anwar-pc URfkill[864]: device_changed_cb: ideapad_bluetooth
Sep 10 16:14:13 anwar-pc URfkill[864]: device_changed_cb: hci0
When disabled, The entries are like this
Sep 10 16:15:31 anwar-pc NetworkManager[957]: <info> [1473502531.8393] manager: WiFi now enabled by radio killswitch
Sep 10 16:15:31 anwar-pc systemd[1]: Starting Load/Save RF Kill Switch Status...
Sep 10 16:15:31 anwar-pc systemd[1]: Started Load/Save RF Kill Switch Status.
Sep 10 16:15:31 anwar-pc URfkill[864]: device_changed_cb: ideapad_bluetooth
Sep 10 16:15:31 anwar-pc URfkill[864]: device_changed_cb: hci0
Sep 10 16:15:32 anwar-pc NetworkManager[957]: <info> [1473502532.0363] manager: (20:54:76:75:5B:C6): new Bluetooth device (/org/freedesktop/NetworkManager/Devices/17)
In the first log, device (20:54:76:75:5B:C6)
is the bluetooth device.