How do I navigate up and down the y-axis in scene view?

The arrow keys only move along the x and z. How do I move my view so that its elevation higher or lower relative to the scene?

http://docs.unity3d.com/Manual/SceneViewNavigation.html

Doesn't give any information about how to navigate up or down along y-axis (changing elevation).

 

That's not quite correct. The arrow keys move forward/back and left/right in directions that are relative to the scene camera. Orbit the scene camera to a different angle, and these keys move you in different directions.

I navigate the scene mainly with the mouse, using the Move and Orbit modes.

 

Try right-clicking in Scene view and using Q and E. I think E goes up and Q goes down.

 

Only way to move up and down is by flying with right mouse held down and using QE. I have tried what you suggest. The arrow keys only move in XZ, even with my view tilted all the way up or down.

 

Your Unity is in some really weird state, then!

 

simply use the hand tool
drag up or down