armature ranges

I have an airplane and i added an armature to each of the wheels. If I need to pull down the wheels (like if the airplane was about to land), I have to position laterally to the plane so that the wheels drop down in the right direction, but if I position the scene as if the airplane was facing me and i pull down the wheels, they don’t move the right way (they start moving sideways).

How can I determine the ranges of an armature ???
How can I determine the axis in wich an armature can rotate

Use the “3d Transform Manipulator” (click the little “hand” icon on the 3d header, then use “Normal” from the Transform Orientation dropdown. This will probably give you the results you’re looking for.

Also, for a wheel controlled by an armature bone, you’ll want the centre of the wheel aligned with the Root of the bone, and probably want the Pivot set to ‘Active Object’ (The Pivot is on the 3d window header)