"Torpedo Shootings Indicator"
 

Hi Subsimmers, I have a small puzzle :)

While on holiday near Gdynia, I had an opportunity to visit ORP B³yskawica museum ship, and one of the items there caught my attention:

https://i.imgur.com/qASdcaz.jpg

It was placed in the part of exhibition dedicated to WW2 submarine squadron, so I guess it was used on submarines. The label said "Torpedo Shootings Indicator", unfortunately no further description was available. The label on the left side says "Ship's plane of symmetry" and the plaque on the lower left is producer's name - "Weapons Workshop of Gdynia Military Port".

I couldn't find this specific device online, though it looks awfully similar to Battenberg course indicator. Any idea what it is and how it works?

It looks like it (may?) be used to calculate ship bearing relative to the sub itself for the torpedo firing soloution. Thats what I would assume at least. Could be wrong

Looks like a variant of an attack disc.

Or a modern looking Maneuvering board.

Yeah, I suppose this is something akin to German Attack Disc. The similar looking Battenberg device was (according to Wiki) used to calculate course to assume position in formation, relative to flagship. Perhaps this is a modification for calculating a course for torpedo to hit the target ship.

Outside white-grey ring near the handle on the bottom seems to show "Kurs". The language looks Polish. Though I may be mistaken as I don't know a word in that language. And so it could have a different meaning than I expect.

It certainly looks like a variation of the attackdisk. But more like the American iswas-banjo disk, as it too had a square gridpattern on it. The German one is quite different. And yes, nice find on that very similar to Battenberg course indicator. On this one the bottom and right arm could be for range, bearing pointers. Then by rotating the underground disk (or upper ring-framework instead) one might be able to measure relative distance (and so calculate relative speed) and minimum relative distance.