Page 186 - The Secret War in the Italian front in WWI (1915-1918)

THE SECRET WAR ON THE ITALIAN FRONT IN WWI (1915 – 1918)

in picture 9.1, the features of codes and ciphers adopted by each group of enemy stations have been
identified, starting their classification and, in some cases, their solution since the summer of 1916 .
7
The report of November-December is of cryptologic interest as it included the interpretation of
several technical terms of the Word Technical Code called Ignaz that Austrian radiotelegraphic
stations used for service communications. It comprised approximately thirty pronounceable
words, out of a total of 140. Each was made of five letters, starting from “ignaz”, which preceded
all dispatches, and including “isaak” that corresponded to “not understood, please repeat”, “knall”
that meant “received correctly”, “fasan” equivalent to “nothing else to transmit”, etc. As will be
shown later in this book, the Sacco’ cryptologic discoveries in the second half of 1916 went far
beyond that technical code.
All the data collected in 1916 confirmed the scarce traffic generated by Austrian field stations
operating on the Italian front, consistently with the limits for transmissions established by the
Austro-Hungarian Headquarters. The effects of these restrictions became more evident in May,
when a group of previously intercepted stations stopped transmission and just two of them, with
the GD and GM codes, remained active daily exchanging service telegrams. The ensuing scarcity
of Austrian dispatches was partly balanced by the interception of telegrams transmitted from field
stations of the Imperial army operating in other geographical areas, such as the Balkan peninsula
and using equal or similar ciphers to those detected on the Italian front.
This necessarily concise description of the activities carried out by the Codroipo Office - assuming
the denomination of ‘Radiotelegraphic Detachment of the Radiotelegraphic Section of the Supreme
Command’ on 1 August 1916 - shows unquestionable ability in the field of interceptions and traffic
analysis, which allowed the collection of a large amount of significant military information. On the
other hand, the Austrian army did not yet have direction finding equipment, which were adopted
systematically on the Italian front only in mid-1917 .
8

aTTeMPTs of elecTronIc counTerMeasures
One of the activities of the interception network managed by the Codroipo Office concerned the
enemy’s air force communications. One of the mentioned reports reads: “on 6 January (1916,
A/N) on the Isonzo front, Austrian aircrafts used for artillery fire control started being equipped
with radiotelegraphic stations […]. Italian radio stations in Trentino such as Arsiero, Coni Zugna
and San Valentino had been reporting this information for quite some time” . In fact, as already
9
mentioned, on 13 November 1915, near the radio station of Arsiero, an enemy aircraft had been
shot down as it was transmitting information to the ground regarding the outcome of artillery fire .
10
The reports issued by the Codroipo Office comprise the plaintext versions of air-to-ground enemy
communications.

7 3 Regiment of the Engineer Corps, Radiotelegraphic Office of Codroipo, Relazioni. Gennaio 1916, op. cit., p.4. The ciphers
rd
of dispatches intercepted in early 1916 mostly featured groups of ten pronounceable letters or 4-5 figures. The latter type was
also used by some Austrian field stations in the Balkans. Another code based on groups of 4-5 non pronounceable letters was
“distributed to all Allied Countries of Central Powers for signal transmission of common interest, which possibly included
warnings to submarines”.
8 M. Ronge, Der Radiohorch, op cit., p.19. The first testing phase started in January 1917. The operational units were equipped
with direction finding devices in the following May.
9 3 Regiment of the Engineer Corps, Radiotelegraphic Office of Codroipo, Relazioni. Gennaio 1916, (Reports. January
rd
1916), op. cit., p.5.
10 General Headquarters of the Engineer Corps, Letter to the Technical Office of the Supreme Headquarters following form
no.1913 of 28 February 2015.

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