I am long-time reader of the U-boat.net forums and have gotten great pleasure from following the discussions over the years.

This morning, I find myself in need of the forum's help. Can anyone educate me about the type of signal lamp or flashlight a uboat crew member might have used to communicate from shore to ship?

The context of the question is a scene in a novel that I am writing in which a uboat picks up an agent from a hostile shore. The landing party needs to signal the uboat from a beach, and I would like the details to be as accuate as possible.

Many thanks,

A. Hiss