It just needs slight adjustments - by adding a few air inlets and heat-generating magic arrays within the long wind channel and body of the Bone Dragon. By warming up the air it breathes in, it boosts its floating ability, allowing the Bone Dragon to drift without the need to flap its wings.
If hovering in mid-air is needed, they just need to heat the air; if speed is needed, they expel the air, and the Bone Dragon restores its aerodynamic form.
As a result, the Bone Dragon has become an atmospheric floating platform, ready to stay on guard in the sky at any time.
However, the Bone Dragon's field of vision is relatively narrow, significantly inferior to that of the Giant Dragon. That's why White Neck is usually sent out along with it, acting as its eyes.
But even with White Neck's sharp eyes scanning the ground, it still couldn't detect any significant movement.