Originally Posted by
Ninthace
If it was that good, submarines would not need attack periscopes
What's the visible horizon from a periscope, though? Can't be far, can it? Knowing where a ship like this was to within a dozen miles is more than good enough if you're not interested in sinking it, just keeping a tail on it's whereabouts.
Edited:
Just had a poke around on the web. No idea how far out of the water a periscope pokes, but if it was 10ft then the horizon limit is about 4 miles. If it's 20ft the horizon limit is about 6 miles. If it was 30ft the horizon limit is just over 7 miles. Less than I thought. May be periscopes poke a lot higher out of the water though. A 50ft high one could see out to a bit over 9 miles. 50ft seems high to me, could well be wrong though.