There was a story from the book Skunk Works that the system was sensitive enough that it occasionally locked onto tiny holes in the roofs of hangars.
The crazy thing about this system too is that, like everything on the SR-71, it was done on a shoestring budget (relatively) and crazy fast. So a navigation system like this was done as a necessary workaround to traditional navigation of the time.
The crazy thing about this system too is that, like everything on the SR-71, it was done on a shoestring budget (relatively) and crazy fast. So a navigation system like this was done as a necessary workaround to traditional navigation of the time.