U-boat searchlight

[Sailor Steve]

Originally Posted by volodya61

To more accurately denote your location for they?

Exactly. It's an old naval dictum that a searchlight might light up your target, but now everyone else knows exactly where you are. Battleships use them to spot destroyers, destroyers use them to spot PT boats, but not the other way around. An airplane is a special case. It's very fast and usually coming right at a u-boat. you can shoot at it or dive, but shining your own light at it is a waste of time.

U-boats didn't have permanent searchlights. They carried portable units, mostly signal lamps.
http://www.uboatarchive.net/DesignSt...ypeIXC-S66.htm