Sunday, June 29, 2014


I have added an index for the top essays and included a permanent link on the upper right side of the site.


USA codes

Army Command and Administrative Network, IBM Radiotype and APO numbers

US Military Strip Ciphers

Einzeldarstellungen aus dem Gebiet der Kryptologie - Hüttenhain’s statements on the State Department’s strip cipher

Professor Wolfgang Franz and OKW/Chi’s mathematical research department
The unfortunate Henry W. Antheil and the State Departments strip cipher

Allen Dulles and the compromise of OSS codes in WWII

Joint Chiefs of Staff evaluation of Office of Strategic Services ciphers

Staff Study on OSS Cryptographic Plan - January 1945

The OSS Bern station and the compromise of State Department codes in WWII

The compromise of the communications of General Barnwell R. Legge, US military attache to Switzerland

Compromise of OWI - Office of War Information communications

Joint Chiefs of Staff evaluation of Office of War Information ciphers

Friday, June 20, 2014

Mega update of the T-34 myth essay

I have added tons of new information in WWII Myths - T-34 Best Tank of the war as well as a detailed listing of the sources. Enjoy!


I have uploaded the report ‘ENGINEERING ANALYSIS OF THE RUSSIAN T34/85 TANK’. Acquired through the CIA’s FOIA office.

Available from my Google docs and Scribd accounts.

Wednesday, June 18, 2014

Detailed report on the Soviet T-34/85 tank

After spending months trying to track down this report I’ve finally managed to get a copy through the CIA’s freedom of information act office.

The report is called ‘ENGINEERING ANALYSIS OF THE RUSSIAN T34/85 TANK’ and contains analysis of all the components of a Soviet T-34/85 tank captured in Korea.

First impressions

The T-34/85 seems to have been improved in terms of performance and reliability compared to the T-34/76 examined by US experts at Aberdeen in WWII. However the transmission failed again.

Also the vehicle examined still had the older 4-speed transmission and no radio onboard. I thought all T-34/85’s had these…
The report is 453 pages long, so it will take me some time to scan it. In the meantime read WWII Myths - T-34 Best Tank of the war.

Saturday, June 14, 2014

Decoded messages in the Finnish national archives

The history of signals intelligence and codebreaking is usually focused on the achievements of the codebreakers of large countries such as the USA, Britain, Germany, Soviet Union etc. However small nations have often managed to achieve great victories in the field of signals intelligence despite being hampered by limited resources.

The Finnish signals intelligence service of WWII was able to solve many foreign cryptosystems including Soviet military and NKVD codes and the diplomatic systems of the United States. Many of these messages can be found in the Finnish national archives. The decoded diplomatic traffic can be found in folders T-21810/4 and T-21810/5.
It is interesting to note that a lot of the traffic from Bern, Switzerland consists of reports on the German military and the war industry. These were probably prepared by the OSS Bern Station and the US military attaché Barnwell R. Legge.

Here are some of these messages:

Sunday, June 8, 2014

The codebreakers of the Japanese Foreign Ministry and the compromise of US codes prior to Pearl Harbor

Imperial Japan entered WWII with three separate codebreaking agencies under the control of the Army, Navy and Foreign Ministry. The Army and Navy signal intelligence agencies intercepted foreign radio traffic and decrypted several military and civilian US, UK, Chinese and Soviet cryptosystems. However relations between these two organizations were strained and in many cases they withheld valuable information from each other. Compared to them the decryption department of the Foreign Ministry was much smaller and had access to limited resources, both in terms of manpower and radio equipment.

Information on the decryption department of the Japanese Foreign Ministry is limited since their archives were destroyed twice during the war. First in a bombing on 25 May 1945 and then in August 1945, when they were ordered by their superiors to burn all secret documents.
According to the recently declassified TICOM report DF-169 ‘Cryptanalytic section Japanese Foreign Office’ this department was established in 1923 and by the end of WWII had approximately 14 officials and 16 clerks. The radio intercept unit supplying it with messages had a station in Tokyo equipped with 10 receivers and 19 operators. They usually intercepted 40-60 messages per day with 100 being the maximum.

The emphasis was on the solution of the codes of the United States, Britain, China and France but some German, Turkish, Spanish, Italian, Swiss, Thailand and Portuguese codes were also read. Despite their limited resources it seems that the Foreign Ministry’s codebreakers were able to achieve their goals mainly thanks to compromised material that they received from their Army and Navy counterparts.
Overview of exploited foreign codes

British codes
In the case of Britain the Government Telegraph Code, R Code, Interdepartmental Cypher and Cypher M were read.

According to one of the Japanese analysts a 4-figure diplomatic codebook and its substitution tables were received from either the Army or the Navy in January 1940, thus a great deal of the traffic could be read. Even though the substitution tables changed every 4-6 months the Japanese were able to get a copy roughly one month after their introduction.
Chinese codes

The Chinese government used several codebooks but only a few were enciphered properly. This allowed the Japanese to solve most of the traffic. One of the codebooks they solved was the ’27 DEMPON’.
French codes

Some French codes and their substitution tables were received from the Army and thus it was possible to solve this traffic. These were called ‘PC 149’, ‘PC 150’, ‘PC 151’ and ‘CGX’ by the Japanese and they were used by the French embassies in Tokyo, Peking, Hanoi, Nanking and Chungking.
It seems that the numbered codes were used mostly for reports on administrative matters while ‘CGX’ carried important reports on the political and military developments.

German codes
Even though Japan and Germany were allies in WWII it seems that the Japanese authorities did not neglect to solve German diplomatic codes. According to DF-169, p2 a German diplomatic unenciphered code of 100.000 values was solved in part and from 1942 it was possible to read some messages even when they were enciphered with additive sequences, thanks to the reuse of the additive pads.

This must have been the German Foreign Ministry’s basic codebook used unenciphered for low level messages, enciphered with reusable additive pads for important messages and also with one time pads for the most important traffic.

 Swiss codes
The code of the Swiss legation in Tokyo was received from the military in summer 1945 and messages were read till the end of the war.

USA codes
The main target of the Foreign Ministry’s codebreakers were the diplomatic systems of the United States. The State Department used the Gray and Brown codes, the enciphered codebooks A1, B1, C1, D1 and the M-138-A strip cipher. By 1940 the Japanese had managed to get copies of Gray, Brown, A1 and several sets of strips of the M-138-A.

With these codes and with the M-138-A strips and keylists the Japanese could read all US diplomatic traffic in the period 1940-41. The importance of this compromise for Japanese foreign policy is something that needs to be investigated by historians.

During the war they received more strips and keylists from their Finnish and German allies.


1). I have uploaded TICOM report DF-169 ‘Cryptanalytic section Japanese Foreign Office’. Acquired through the NSA’s FOIA office.

Available from my Google docs and Scribd accounts.
2). I have added information on the codebreakers of the Japanese Foreign Ministry in Japanese codebreakers of WWII.

Thursday, June 5, 2014

Operation Overlord 70th anniversary

On 6 June 1944 the Anglo-Americans landed in Normandy, France and proceeded to liberate Nazi occupied Europe.

The anniversary of this operation will undoubtedly lead to statements in magazines and newspapers attributing the success of ‘Overlord’ to a disinformation campaign. According to this view the Germans could have defeated the landings but they were tricked into holding most of their forces in reserve so they could be used against the ‘real’ landings expected near Pas de Calais.
For an opposing view read the following essays:

2). Normandy 1944 – What-if scenarios and the Fortitude deception

4). The Jellyfish radio-teletype link

6). Book review – Normandy 1944

GCHQ Middle East base

GCHQ's BEYOND TOP SECRET Middle Eastern internet spy base