No. An iPad with cellular actually has GPS hardware and can be used whether cellular is activated or not. For some reason though, Go will say the GPS signal is weak.
WiFi only iPad (no SIM card slot) does not have GPS hardware at all. It's iOS has other tricks for location services, mainly using a database of fixed WiFi access points and their addresses. This database is populated by devices that do have both and phone home to the cloud with the information. Called Crowd Sourcing, similar to how Google gets traffic information.
There are rumors that a WiFi only iPad can get GPS information from an iPhone connected by hotspot, but this has not been confirmed. There are apps that will do it for you though.
Now whether Go or Fly can pick up on the passed on GPS information is another story.