When QCing power infrastructure I am having to zoom into every gap and check to make sure the line makes sense (not going through the mountain). I typically check for odd spacing between the pylons and zoom into the imagery. What I want to accomplish is have some tool identify where the 'line of sight' would intersect with the DTED_Level_2. Is there a tool in ArcMap 10.1 that can accomplish this? I have 3D Analyst installed.
Are all of your pylons (points) the same height? If so you should set the base height of your points to be from the dted. Then you can extrude the points to a set height (say 90'). If you already have a line then just set the base height to be floating from the dted at the height of the pylon. Lastly you could actually copy the line vertically to a set height using edit 3d