The supersonic torpedo was the first TS stamped documents I saw when I came in the AF. It wasn't until '01 when portions of what we knew about it ended up in Janes Defense.
It 'cavitates" (sp?) at (like a bad football pass) at incredible speed, causing so much friction the water around it turns to steam and the whole thing travels in a sort of air pocket.
It could be fired at an entire carrier battle group and make everything dissapear, just like that.
Not good.
Then the Russians needed money and put the plans on the open market.