SH5 Atmosphere?

[Kapitanleutnant]

Originally Posted by Sentinel VI

Realistically, a Type VII u boat only had a visual range of about 6.6 nm, or 12.2 km.
Obviously, the advent of marine radars greatly increased detection range to over the horizon.

That's the distance to the horizon, isn't it?
Lookouts could often spot a ship beyond the horizon by masts or smoke plumes. I've heard that spotting ships at ranges up to 15-20km were not outside the realm of possiblity by looking for these things.