The submarine quiz thread!

[Sir Big Jugs]

G'Day all. It is my pleasure to announce the Submarine forums quiz thread created.

This is a thread where users of the forum may challenge other members, ask very tricky questions or have them identify something.

The rules are easy:

The first one to post the correct answer to a question, posts a new question and so on.

IMPORTANT!

In case no new question has appeared within 24 hours since the last one was solved, ANY other forum member may post a new question. Only one question at a time please.


I'll start:



I am looking for a specific sub class/single sub.

Hints:



Only one was ever built.

In one important way it's design purpose was unique compared to ALL other submarines in the world! It did not, however operate in the conditions it was designed for.

It was the [won't tell, would be too easy] submarine in ANY navy of the world at the time.

Was used operationally.

Scrapped in Belgium.

It had one 12.7mm MG.

Good Luck!