@Donity, what you're describing sounds like the "virtual fence" SAFE feature that prevents a model from getting too far away. When the plane exceeds a certain distance from its starting point, it takes over control, turns itself around, holds straight and level flight for a few seconds, then wags its wings as a signal to the pilot before relinquishing control.
Both the
E-flite Apprentice STS 1.5m (with LAS and GPS) and the
HobbyZone Carbon Cub S+ 1.3m have that feature enabled. The distance thresholds are 150 meters and 100 meters, respectively. I believe those are the only two models in RealFlight Trainer Edition (I don't expect to see it on the Habu which you mentioned), but if I'm wrong you'll of course be able to clearly recognize the behavior if it occurs elsewhere.
In the full version of RealFlight you can edit models to make all kinds of changes, including turning off that virtual fence behavior. The aircraft editor is an advanced feature that is not present in Trainer Edition, though.
One of the most important skills for a new pilot to learn is the ability to fly within a constrained area. It is far too easy and far too common for beginners to let the model get farther away than they realize, which can be disastrous. Rather than get frustrated by those limitations, I encourage you to let them help you form good habits.
Most of the models offered in RFTE--including other variants of the Apprentice STS--do not employ that particular SAFE feature. You can fly those unrestricted. As you advance, you may find you want the vastly increased selection of models and the ability to edit that are part of the full RealFlight 9.5S edition.