How to disable the No SIM Card Installed warning in iPad when using it without SIM?

I have not managed to find a way to disable the warning No Sim Card Installed while using iPad Air without sim-card. I disabled using Mobile data in all parts of settings. I have done this now in three generation of iPads unsuccessfully. The notice window looks like this

How can you disable the warning No Sim Card in iPads?

To prevent this message you can continually keep your iPad in Airplane Mode. Whilst not recommended to be on all the time, it provides a solution. If you turn WiFi on you should have no issues using internet features and services.

Ask Siri to "turn off mobile data". Worked for me on an iPad 4 with iOS 10.2. Found in this Apple discussion.