I just added this beautiful US Mk14 MOD6 Torpedo guidance gyroscope to my inert torpedo artifact collection. The interesting thing to me is that it looks to be a very similar copy of a WW2 era German guidance gyroscope for their G7A torpedo.
The G7a(TI) and the electric G7e(TII) / G7e(TIII) variants all used the standard GA VIII gyroscope for straight runs (with the possibility for presetting a course up to +/- 90 degrees from the launching course. Your second series of photos show the GA VIII ("
Geradelauf Apparat", type 8).
It has a low serial number of #10, so I'm guessing this was experimental copy based off of a captured German design?
Your MOD 6 gyroscope is obviously copied from the german GA VIII Lut II gyroscope (they even kept the "LUT" designation on the transportcrate ;-) ). LUT =
Lageunabhäniger Torpedo (I'm adding a explanation of this below). It was a gyroscope with "program steering", ie a preset course of automated loops after an initial straight run. It was a very successful invention used with success in attacks at convoys, were an initial miss would still give a chance for a hit on the target or another vessel in the convoy.
Fat/Lut drew a lot of interest in allied navies post WW2. I recently found massive correcpondance in the norwegian national archives showing demands for Fat and Lut gyroscopes to be delivered from Norway, by several of the new NATO-allies around 1950 (we had a huge amount of german torpedoes and -parts left after the war). I suppose US had secured their own supply of german gyroscopes, but Norway supplied hundreds of gyroscopes to countries like England, France, Portugal and even Sweden in the 1950's (Sweden also got other parts, including complete torpedoes - obviously used in their own torpedo-development, and very visible when comparing parts and tools for the TP61's to the original WW2 german torpedoes: A lot of the material is 100% identical, and we could use german tools on the swedish torpedoes, as well as swedih tools on the german torpeoes).
Here is a brief description of FAT/LUT which I posted in another forum a while back (I have no idea wether the US copy incorporated changes from the original german Lut-settings):
Fat/Lut was different types of programsteering-mechanisms for german torpedoes. Together with the acoustic seekers, these devices were deemed the most crucial german torpedodesign-elements during WW2 by the post-war allied evaluation.
Fat = "Federapparat" or "Flächenabsuchender Torpedo" (spring device or area searching torpedo)
Lut = "Lageunabhängiger Torpedo" (bearing independent torpedo)
The following variants were developed:
* Fat I
* Fat II
* Fat III (later renamed Lut I)
* Lut II (+ a special variant of the Lut II made for the G7e(TIIId) "Dackel" torpedo with a very long initial straight running distance of 36000m).
The programsteering consisted of a mechanical construction coupled to the gyroscope, which changed the torpedo's course over time in different patterns after an initial straight running distance.
Fat I ("S-shaped" loop-patterns):
* The initial straight distance could be set from a miniumum of 500 m to a maximum of 1500 m.
* Two loop-patterns available: "short" and "long", and in addition there were a choice of right or left turns (ie a total of 5 settings on the Fat-mechanism).
* For "short" loops, the straight distance between turns was 800 m, with a total width of the pattern-search of 1140 m
* For "long" loops, the straight distance between turns was 1500 m, and a total width of the pattern-search of 1840 m.
* The turning radius for both patterns were 170 m.
Fat II ("S-shaped loops or circular patterns):
* The same data as for Fat Il, but an additional choice for "circular" pattern, where the torpedo would run in a circle after the initial straight-run. This was an option primary used by uboats against attacking surface-ships that ran a zig-zag pattern hunting the u-boat (the goal was to locate the torpedo's circle-run just ahead of the attacking ship, hoping for a "lucky" hit.
Fat III / Lut I ("zig-zag" pattern):
* Initial torpedocourse can be chosen, so the torpedoplatform don't need to change it's bearing to an optimal course for torpedolaunch.
* The "Lut-speeed" (ie the resulting advance-speed of the torpedo, considering the zig-zag pattern can be chosen, and subsequently the straight legs between turns will be adjusted accordingly).
Lut II:
* Same as Lut I, but even slower Lut-speeds could be chosen.
The following torpedoes with programsteering were fielded during WW2:
* G7a(TI Fat I)
* G7a(TI Lut I)
* G7a(TI Lut II)
* G7a(TIü Lut II)
* G7e(TIII Fat II)
* G7e(TIIIa Fat II)
* G7e(TIIIa Lut I)
* G7e(TIIIa Lut II)
* G7e(TIIId Lut II)
G7e torpedoes with programstering-mechanisms (I have not been able to determine if this was valid for Fat II, but certainly for Lut I and Lut II) were equipped with "ausschiebbaren vertikalflossen" - ie expanding vertical fins. These helped keeping the torpedo stable (ie not rotating on it's longitunal axis) during turns.