Latitude E7270 - disabling wifi

I have been given a shiny new Dell Latitude E7270 laptop at work. I regularly travel overseas and work on the plane. My previous laptop had a switch on the right hand side of the laptop to activate or disable wifi. The E7270 doesn't have this and I am wondering how to switch of wifi so  I can work whilst in the air.

I've toggled the Fn+ PrtScr keys but it only seems to toggle Bluetooth. I've also scanned the forums and net, but can only find reference to high level fixes or previous versions of the Dell which had a switch.

I can't believe there isn't a flight safe mode!?