a1troll - Why don't you read something about MAC and the reasons for high-altitude ASW, instead of wasting bandwidth and oxygen?
Let me explain this in very simple terms. I am well aware of high-alt ASW, including the gliding torpedo. However, the most often stated reason for doing it is that multistatic active coherent acoustics and very large sonobuoy loads allow you to cover a wide search area, and you therefore stay high to keep your buoy field within line of sight.
Yes, I have heard the argument about defeating sub-based missile defenses, but not as often as the other one. And in case you have the wrong impression that is not the only reason for a gliding torpedo - it's to drop the fish in the right zip code.