Keywords
Adriatic
Kriegsmarine
cypher machines
Enigma
micro CT investigation
How to Cite
Abstract
This article presents the results of microtomographic analysis of the rotor block of an Enigma machine M4 recovered from the wreck of the German minesweeper R15 in the upper Adriatic Sea (sunk on 16 April 1945). The device (serial number M 15648) was examined using visual inspection and MicroCT. Initial analysis enabled identification of the rotor sequence (Walzenlage) and external wheel positions, while higher-resolution scanning revealed internal rotor settings (Ringstellung). Based on the place and time of the sinking of the R15, it is plausible that the operators of M 15648 used the naval key Hermes within the code network Sud.
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Copyright (c) 2026 Andrej Gaspari, Miha Hren