Central Bureau
Encyclopedia
The Central Bureau was one of two Allied Sigint organisations in the South West Pacific area (SWPA) during World War II. Central Bureau was attached to the HQ of the Allied Commander of the South West Pacific area, Douglas MacArthur
. The other unit was the joint RAN
/USN
Fleet Radio Unit
, Melbourne
(FRUMEL
), which was subordinate to the Commander of the USN 7th Fleet
. Central Bureau's role was to research and decrypt
intercepted IJA (land and air) traffic and work in close co-operation with other SIGINT centres in the USA, United Kingdom and India
before the War started, and was not fully dependent on the U.S. Navy for that type of information. However, most of the signals intelligence he received was from the Navy unit, Station CAST
, originally at Cavite in the Manila Navy Yard
, and evacuated to Corregidor
after Japanese successes. Prior to the war, it had to be sent by courier, which caused some delay and annoyance.
General Douglas MacArthur escaped from Corregidor in the Philippines in a PT boat to Mindanao and flew to Australia from Del Monte on a Boeing B-17 Flying Fortress. He made his way to Melbourne, arriving there on 22 March 1942.
The Signals Intelligence units operating in Australia at the time of MacArthur's arrival in Melbourne were as follows:
and, eventually, after evacuation from Corredigor by submarine,
One of his first decisions when he arrived in Melbourne was to expand the SIGINT operations already existing in Australia. Some personnel of the United States Navy crypto group in the Philippines, evacuated in early January 1942, was operating in Melbourne. They were responsible for channeling all SIGINT information to OP-20-G
in Washington.
MacArthur was not happy to depend on the Navy's discretion in handling his SIGINT requirements. He felt he had experienced problems with such an arrangement when he was in Manila
. MacArthur's Intelligence Officer (G-2) was Major General Charles A. Willoughby.
Brigadier General Spencer B. Akin, MacArthur's Chief Signals Officer held discussions with Major General Colin Simpson
. They agreed that a Research and Control Centre to handle Signals Intelligence (SIGINT) was needed. MacArthur subsequently issued orders for the formation of two complementary groups:
.
General MacArthur advised Washington of his decision in a dispatch on 1 April 1942. He described the role of the group as "the interception and cryptanalyzing of Japanese intelligence".
A small group from Australian Naval Intelligence, led by Paymaster Commander R.E. Eric Nave
and Professor Arthur Dale Trendall
also became part of the secret new unit. They had been working on Japanese diplomatic codes.
Central Bureau was established in a gabled, ivy-clad mansion called "Cranleigh" in Domain Road, at South Yarra
, Melbourne.
Central Bureau's role was to research and decrypt army and air intercept traffic and work in close co-operation with other SIGINT centres in the USA, United Kingdom and India. Mic Sandford was appointed AIF Commanding Officer at Central Bureau.
Major Abraham "Abe" Sinkov
, a mathematician, was appointed Assistant Director of Central Bureau. Sinkov had previously been a senior cryptographer in the US Army Signals Intelligence Service under William F. Friedman
. Sinkov had previously been in charge of an intercept station in Panama. He had visited Britain in 1941 to facilitate the exchange of cryptographic information.
The existing experienced RAAF intercept Kana
operators at Townsville
were assigned to the new Central Bureau. The RAAF at the time had a number of Kana operators being trained and were about to train a further 13 WAAAF
personnel. (Katakana
is one of the syllabic forms of written Japanese).
The cryptanalysts who had operated from the Malinta Tunnel
during the Battle of Corregidor
got out to Australia by submarine in two groups. Their equipment was pushed into Manila Bay
. They were used to assist the Australian Wireless Group units. A group of cryptographic, cryptanalytic and translator personnel from the Japanese section of the Washington Signal Intelligence Service were also moved to Australia. More Australians were also recruited to Central Bureau after it was established.
Major General Akin's Executive Officer, Joe R. Sherr had been evacuated from the Philippines and was responsible for arranging for the first group of US "SIGINT" personnel to come to Australia.
Initially Central Bureau was made up of 50% American, 25% Australian Army and 25% RAAF personnel.
On 25 April 1942 the small RAAF Intercept Station operating in two back-to-back houses at 21 Sycamore Street and 24 French Street in the suburb of Pimlico
in Townsville was given its new name of No. 1 Wireless Unit and became part of Central Bureau.
The newly named Unit included 7 RAAF, 1 AMF and 4 United States Army personnel in No. 1 Wireless Unit at Townsville. This RAAF Unit had started earlier in March 1942 as a small intercept station located in the initial two houses at Pimlico under Wing Commander Booth.
Commander Nave
moved to Central Bureau in mid-1942 from the combined Australian Navy/U.S. Navy operation in Melbourne known as FRUMEL, which was put under U.S. Navy control in mid-1942. Although he headed up the “Solutions” division there, most records indicate he personally dealt with minor Japanese naval codes and simple substitution ciphers in spite of his Japanese language capability and long history with Japanese codes. Colonel Sinkov and his American staff worked on the high-level Japanese Army codes.
Central Bureau did not break any high level Japanese Army codes until mid-1943 with the Water Transport code. Later that year, one main line Japanese Army code was broken with help from a buried trunk found at Sio, New Guinea
, left by retreating Japanese Army cryptographers.
By 6 July 1942 the intercept operator numbers at Central Bureau had increased from six to twenty nine.
On 20 July 1942, General MacArthur moved his Headquarters to Brisbane
. Central Bureau immediately relocated to Brisbane, establishing its headquarters in "Nyrambla", a huge house at 21 Henry Street, high on a hill in the suburb of Ascot
, not far from the new American airfield at Eagle Farm Airport
. Another source indicated that CBI's Headquarters were at Ascot Park at Hamilton
.
Another separate Intelligence operation was located in the same general area in a building called "Palma Rosa" at 9 Queens Road, Hamilton. "Palma Rosa" was commandeered by the Counter Intelligence Corps, G-2 Section, Headquarters U.S. Army Forces in the Far East (U.S.A.F.F.E.).
Central Bureau had banks of IBM
punched card
equipment, which were used by the cryptanalysts to help analyze intercepted cyphertext. They were located in the garage at the rear of 21 Henry Street
The IBM machines were later moved from the garage at 21 Henry Street to the Fire Station at Ascot Park. After the IBM machines were removed from 21 Henry Street the garage was occupied by No. 11 Australian Cypher Section. The garage was filled with Typex
machines which were operated mostly by Australian Women's Army Service
(AWAS) personnel.
Beginning in January 1942, U.S. Navy stations in Hawaii (Station HYPO
), Cavite/Corregidor (Station CAST
) and OP-20-G (Station NEGAT, at Washington) began issuing formal intelligence decrypts far in advance of the U.S. Army or Central Bureau. FRUMEL in Australia obtained IBM equipment in 1942 to replace that which had been left behind in Manila Bay on leaving Corregidor and employed it throughout their tenure in Melbourne.
Central Bureau moved to a new location at 45 Eldernall Avenue, Hamilton sometime later.
Japanese POW's were interrogated at a house called "Tighnabruaich" at Indooroopilly
in Brisbane.
Central Bureau at 21 Henry Street, Ascot in Brisbane decrypted a Japanese Army Air/Ground signal intercepted by 51 Wireless Section in Darwin
that contained Admiral Isoroku Yamamoto's itinerary for an upcoming trip to Rabaul
. Admiral Yamamoto, was the Commander in Chief of the Combined Japanese Fleet, the architect of the attack on Pearl Harbor
. Central Bureau reportedly sent the decrypted message to FRUMEL where it was reportedly translated by a U.S. Navy linguist. Although Central Bureau may have decrypted the message, the interception of his flight was based on decrypts of Japanese naval messages by FRUPAC/Station HYPO in Hawaii, FRUMEL, OP-20-G in Washington and Station AL on Guadalcanal. Major Lasswell USMC in Hawaii decrypted the Japanese Naval message first and Captain Layton (Pacific Fleet Intelligence in Hawaii) gave it to Admiral Nimitz who authorized a shootdown attempt after determining from ComNavAirSoPac that it could be done with by one of his Army Air Corp units on Guadalcanal.
Central Bureau is probably the precursor to the Defence Signals Directorate
.
Douglas MacArthur
General of the Army Douglas MacArthur was an American general and field marshal of the Philippine Army. He was a Chief of Staff of the United States Army during the 1930s and played a prominent role in the Pacific theater during World War II. He received the Medal of Honor for his service in the...
. The other unit was the joint RAN
Royal Australian Navy
The Royal Australian Navy is the naval branch of the Australian Defence Force. Following the Federation of Australia in 1901, the ships and resources of the separate colonial navies were integrated into a national force: the Commonwealth Naval Forces...
/USN
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
Fleet Radio Unit
Fleet Radio Unit
Fleet Radio Units were the major centers for Allied cryptological and signals intelligence during the Pacific Campaign of World War II. Initially two FRUs were established in the Pacific, one at Pearl Harbor, Hawaii, called Station HYPO or FRUPAC , and the other, called Station CAST or Belconnen,...
, Melbourne
Melbourne
Melbourne is the capital and most populous city in the state of Victoria, and the second most populous city in Australia. The Melbourne City Centre is the hub of the greater metropolitan area and the Census statistical division—of which "Melbourne" is the common name. As of June 2009, the greater...
(FRUMEL
FRUMEL
Fleet Radio Unit, Melbourne was a United States-Australian-British signals intelligence unit, based in Melbourne, Australia during World War II. It was one of two major Allied signals intelligence units, called Fleet Radio Units, in the Pacific theatres, the other being FRUPAC , in Hawaii...
), which was subordinate to the Commander of the USN 7th Fleet
United States Seventh Fleet
The Seventh Fleet is the United States Navy's permanent forward projection force based in Yokosuka, Japan, with units positioned near Japan and South Korea. It is a component fleet force under the United States Pacific Fleet. At present, it is the largest of the forward-deployed U.S. fleets, with...
. Central Bureau's role was to research and decrypt
Cryptanalysis
Cryptanalysis is the study of methods for obtaining the meaning of encrypted information, without access to the secret information that is normally required to do so. Typically, this involves knowing how the system works and finding a secret key...
intercepted IJA (land and air) traffic and work in close co-operation with other SIGINT centres in the USA, United Kingdom and India
Background
General Douglas MacArthur had his own signals intelligence unit, Station 6, while he was in command in the PhilippinesPhilippines
The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...
before the War started, and was not fully dependent on the U.S. Navy for that type of information. However, most of the signals intelligence he received was from the Navy unit, Station CAST
Station CAST
Station CAST was the United States Navy signals monitoring and cryptographic intelligence fleet radio unit at Cavite Navy Yard in the Philippines, until Cavite was captured by the Japanese forces in 1942, during World War II. It was an important part of the Allied intelligence effort, addressing...
, originally at Cavite in the Manila Navy Yard
U.S. Naval Station Sangley Point
Naval Station Sangley Point was a communication and hospital facility of the United States Navy which occupied the northern portion of the Cavite City peninsula and is surrounded by Manila Bay, approximately eight miles southwest of Manila, the Philippines. The station was a part of the Cavite...
, and evacuated to Corregidor
Corregidor
Corregidor Island, locally called Isla ng Corregidor, is a lofty island located at the entrance of Manila Bay in southwestern part of Luzon Island in the Philippines. Due to this location, Corregidor was fortified with several coastal artillery and ammunition magazines to defend the entrance of...
after Japanese successes. Prior to the war, it had to be sent by courier, which caused some delay and annoyance.
General Douglas MacArthur escaped from Corregidor in the Philippines in a PT boat to Mindanao and flew to Australia from Del Monte on a Boeing B-17 Flying Fortress. He made his way to Melbourne, arriving there on 22 March 1942.
The Signals Intelligence units operating in Australia at the time of MacArthur's arrival in Melbourne were as follows:
- No. 4 Australian Special Wireless Section at Park Orchards near Ringwood in Melbourne
- A small Diplomatic and Press intercept section at Park Orchards
- A Diplomatic cryptographic and intelligence section at Victoria Barracks, Melbourne
- Some British Army Signals personnel from the Far East Combined BureauFar East Combined BureauThe Far East Combined Bureau, an outstation of the British Government Code and Cypher School, was set up in Hong Kong in March 1935, to monitor Japanese, and also Chinese and Russian intelligence and radio traffic...
who had escaped from Java - A small RAAFRoyal Australian Air ForceThe Royal Australian Air Force is the air force branch of the Australian Defence Force. The RAAF was formed in March 1921. It continues the traditions of the Australian Flying Corps , which was formed on 22 October 1912. The RAAF has taken part in many of the 20th century's major conflicts...
Intercept section in Darwin - A small RAN intercept and Direction Finding (D/F) organisation
- A small RAN cryptographic and intelligence section at the Navy Office in Melbourne
and, eventually, after evacuation from Corredigor by submarine,
- the personnel of Station CAST, the US Navy SIGNIT group in the Far East
One of his first decisions when he arrived in Melbourne was to expand the SIGINT operations already existing in Australia. Some personnel of the United States Navy crypto group in the Philippines, evacuated in early January 1942, was operating in Melbourne. They were responsible for channeling all SIGINT information to OP-20-G
OP-20-G
OP-20-G or "Office of Chief Of Naval Operations , 20th Division of the Office of Naval Communications, G Section / Communications Security", was the US Navy's signals intelligence and cryptanalysis group during World War II. Its mission was to intercept, decrypt, and analyze naval communications...
in Washington.
MacArthur was not happy to depend on the Navy's discretion in handling his SIGINT requirements. He felt he had experienced problems with such an arrangement when he was in Manila
Manila
Manila is the capital of the Philippines. It is one of the sixteen cities forming Metro Manila.Manila is located on the eastern shores of Manila Bay and is bordered by Navotas and Caloocan to the north, Quezon City to the northeast, San Juan and Mandaluyong to the east, Makati on the southeast,...
. MacArthur's Intelligence Officer (G-2) was Major General Charles A. Willoughby.
Brigadier General Spencer B. Akin, MacArthur's Chief Signals Officer held discussions with Major General Colin Simpson
Colin Hall Simpson
Major General Colin Hall Simpson, CBE, MC, VD was an Australian Army officer who rose to the rank of major general as Signal Officer in Chief during the Second World War...
. They agreed that a Research and Control Centre to handle Signals Intelligence (SIGINT) was needed. MacArthur subsequently issued orders for the formation of two complementary groups:
- An Intercept Organisation known initially as No. 5 Wireless Section
- A Research and Control Centre known as the Central Bureau.
Central Bureau's origins
Central Bureau was a joint American-Australian SIGINT organisation, established on 15 April 1942 under the command of Major General S. B. Akin with headquarters based in MelbourneMelbourne
Melbourne is the capital and most populous city in the state of Victoria, and the second most populous city in Australia. The Melbourne City Centre is the hub of the greater metropolitan area and the Census statistical division—of which "Melbourne" is the common name. As of June 2009, the greater...
.
General MacArthur advised Washington of his decision in a dispatch on 1 April 1942. He described the role of the group as "the interception and cryptanalyzing of Japanese intelligence".
A small group from Australian Naval Intelligence, led by Paymaster Commander R.E. Eric Nave
Eric Nave
Captain Eric Nave was a Navy Paymaster Commander and an Australian cryptographer, before and during World War II. He served in the Navy from 1917 to 1949. As a midshipman in the 1920s, he was required to learn a foreign language and chose Japanese: with French and German you got sixpence a day...
and Professor Arthur Dale Trendall
Arthur Dale Trendall
Arthur Dale Trendall AC CMG was a New Zealand-born Australian art historian and classical archaeologist whose work on identifying the work of individual artists on Greek ceramic vessels at Apulia and other sites earned him international prizes and a papal knighthood...
also became part of the secret new unit. They had been working on Japanese diplomatic codes.
Central Bureau was established in a gabled, ivy-clad mansion called "Cranleigh" in Domain Road, at South Yarra
South Yarra, Victoria
South Yarra is a suburb in Melbourne, Victoria, Australia, 4 km south-east from Melbourne's central business district. Its Local Government Area are the Cities of Stonnington and Melbourne...
, Melbourne.
Central Bureau's role was to research and decrypt army and air intercept traffic and work in close co-operation with other SIGINT centres in the USA, United Kingdom and India. Mic Sandford was appointed AIF Commanding Officer at Central Bureau.
Major Abraham "Abe" Sinkov
Abraham Sinkov
Dr. Abraham Sinkov was a US cryptanalyst.-Biography:Sinkov, the son of immigrants from Russia, was born in Philadelphia, but grew up in Brooklyn. After graduating from Boys High School—what today would be called a "magnet school" -- he took his B.S. in mathematics from City College of New York...
, a mathematician, was appointed Assistant Director of Central Bureau. Sinkov had previously been a senior cryptographer in the US Army Signals Intelligence Service under William F. Friedman
William F. Friedman
William Frederick Friedman was a US Army cryptographer who ran the research division of the Army's Signals Intelligence Service in the 1930s, and parts of its follow-on services into the 1950s...
. Sinkov had previously been in charge of an intercept station in Panama. He had visited Britain in 1941 to facilitate the exchange of cryptographic information.
The existing experienced RAAF intercept Kana
Kana
Kana are the syllabic Japanese scripts, as opposed to the logographic Chinese characters known in Japan as kanji and the Roman alphabet known as rōmaji...
operators at Townsville
Townsville, Queensland
Townsville is a city on the north-eastern coast of Australia, in the state of Queensland. Adjacent to the central section of the Great Barrier Reef, it is in the dry tropics region of Queensland. Townsville is Australia's largest urban centre north of the Sunshine Coast, with a 2006 census...
were assigned to the new Central Bureau. The RAAF at the time had a number of Kana operators being trained and were about to train a further 13 WAAAF
Women's Auxiliary Australian Air Force
The Women's Auxiliary Australian Air Force was formed in March 1941 after considerable lobbying by women keen to serve and by the Chief of the Air Staff who wanted to release male personnel serving in Australia for service overseas. The WAAAF was the first and largest of the World War II...
personnel. (Katakana
Katakana
is a Japanese syllabary, one component of the Japanese writing system along with hiragana, kanji, and in some cases the Latin alphabet . The word katakana means "fragmentary kana", as the katakana scripts are derived from components of more complex kanji. Each kana represents one mora...
is one of the syllabic forms of written Japanese).
The cryptanalysts who had operated from the Malinta Tunnel
Malinta Tunnel
The Malinta Tunnel is a tunnel complex built by the United States Army Corps of Engineers on the island of Corregidor in the Philippines. It was initially used as a bomb-proof storage and personnel bunker, but was later equipped as a 1,000-bed hospital. The main tunnel, running east to west, is ...
during the Battle of Corregidor
Battle of Corregidor
The Battle for Corregidor was the culmination of the Japanese campaign for the conquest of the Philippines. The fall of Bataan on 9 April 1942 ended all organized opposition by the U.S...
got out to Australia by submarine in two groups. Their equipment was pushed into Manila Bay
Manila Bay
Manila Bay is a natural harbor which serves the Port of Manila , in the Philippines.The bay is considered to be one of the best natural harbors in Southeast Asia and one of the finest in the world...
. They were used to assist the Australian Wireless Group units. A group of cryptographic, cryptanalytic and translator personnel from the Japanese section of the Washington Signal Intelligence Service were also moved to Australia. More Australians were also recruited to Central Bureau after it was established.
Structure
Central Bureau comprised:- administrative personnel
- supply personnel
- cryptographic personnel
- cryptanalytic personnel
- interpreters
- translators
- a field section which included the intercept and communications personnel
Major General Akin's Executive Officer, Joe R. Sherr had been evacuated from the Philippines and was responsible for arranging for the first group of US "SIGINT" personnel to come to Australia.
Initially Central Bureau was made up of 50% American, 25% Australian Army and 25% RAAF personnel.
On 25 April 1942 the small RAAF Intercept Station operating in two back-to-back houses at 21 Sycamore Street and 24 French Street in the suburb of Pimlico
Pimlico, Queensland
For other uses, see Pimlico .Pimlico, is a suburb of Townsville, Australia. Townsville's largest private hospital, the Mater Misericordiae Hospital is located here. The local high school is Pimlico State High School....
in Townsville was given its new name of No. 1 Wireless Unit and became part of Central Bureau.
The newly named Unit included 7 RAAF, 1 AMF and 4 United States Army personnel in No. 1 Wireless Unit at Townsville. This RAAF Unit had started earlier in March 1942 as a small intercept station located in the initial two houses at Pimlico under Wing Commander Booth.
Commander Nave
Eric Nave
Captain Eric Nave was a Navy Paymaster Commander and an Australian cryptographer, before and during World War II. He served in the Navy from 1917 to 1949. As a midshipman in the 1920s, he was required to learn a foreign language and chose Japanese: with French and German you got sixpence a day...
moved to Central Bureau in mid-1942 from the combined Australian Navy/U.S. Navy operation in Melbourne known as FRUMEL, which was put under U.S. Navy control in mid-1942. Although he headed up the “Solutions” division there, most records indicate he personally dealt with minor Japanese naval codes and simple substitution ciphers in spite of his Japanese language capability and long history with Japanese codes. Colonel Sinkov and his American staff worked on the high-level Japanese Army codes.
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
, left by retreating Japanese Army cryptographers.
By 6 July 1942 the intercept operator numbers at Central Bureau had increased from six to twenty nine.
On 20 July 1942, General MacArthur moved his Headquarters to Brisbane
Brisbane
Brisbane is the capital and most populous city in the Australian state of Queensland and the third most populous city in Australia. Brisbane's metropolitan area has a population of over 2 million, and the South East Queensland urban conurbation, centred around Brisbane, encompasses a population of...
. Central Bureau immediately relocated to Brisbane, establishing its headquarters in "Nyrambla", a huge house at 21 Henry Street, high on a hill in the suburb of Ascot
Ascot, Queensland
Ascot is a predominantly affluent residential suburb of Brisbane, Queensland, Australia, characterised by large Queenslander homes. Located from Brisbane, the suburb is well catered for in terms of public transport with many bus and train services departing from Ascot railway station...
, not far from the new American airfield at Eagle Farm Airport
Eagle Farm Airport
Eagle Farm Airport was a small airport located south-west of Brisbane, Queensland, Australia.-History:An area located near Eagle Farm Racecourse was initially used as a landing field in 1922 and Eagle Farm Aerodrome was officially opened in 1925...
. Another source indicated that CBI's Headquarters were at Ascot Park at Hamilton
Hamilton, Queensland
Hamilton is an inner northern suburb of Brisbane, Australia, lying on the north bank of the Brisbane River along Bulimba Reach. The area is hilly with views of the Brisbane central business district....
.
Another separate Intelligence operation was located in the same general area in a building called "Palma Rosa" at 9 Queens Road, Hamilton. "Palma Rosa" was commandeered by the Counter Intelligence Corps, G-2 Section, Headquarters U.S. Army Forces in the Far East (U.S.A.F.F.E.).
Central Bureau had banks of IBM
IBM
International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
punched card
Punched card
A punched card, punch card, IBM card, or Hollerith card is a piece of stiff paper that contains digital information represented by the presence or absence of holes in predefined positions...
equipment, which were used by the cryptanalysts to help analyze intercepted cyphertext. They were located in the garage at the rear of 21 Henry Street
The IBM machines were later moved from the garage at 21 Henry Street to the Fire Station at Ascot Park. After the IBM machines were removed from 21 Henry Street the garage was occupied by No. 11 Australian Cypher Section. The garage was filled with Typex
Typex
In the history of cryptography, Typex machines were British cipher machines used from 1937. It was an adaptation of the commercial German Enigma with a number of enhancements that greatly increased its security....
machines which were operated mostly by Australian Women's Army Service
Australian Women's Army Service
The Australian Women's Army Service or "AWAS" was a women's service established on 13 August 1941 to "release men from certain military duties for employment in fighting units".-Formation / Structure:...
(AWAS) personnel.
Beginning in January 1942, U.S. Navy stations in Hawaii (Station HYPO
Station HYPO
Station HYPO, also known as Fleet Radio Unit Pacific was the United States Navy signals monitoring and cryptographic intelligence unit in Hawaii during World War II. It was one of two major Allied signals intelligence units, called Fleet Radio Units in the Pacific theaters, along with FRUMEL in...
), Cavite/Corregidor (Station CAST
Station CAST
Station CAST was the United States Navy signals monitoring and cryptographic intelligence fleet radio unit at Cavite Navy Yard in the Philippines, until Cavite was captured by the Japanese forces in 1942, during World War II. It was an important part of the Allied intelligence effort, addressing...
) and OP-20-G (Station NEGAT, at Washington) began issuing formal intelligence decrypts far in advance of the U.S. Army or Central Bureau. FRUMEL in Australia obtained IBM equipment in 1942 to replace that which had been left behind in Manila Bay on leaving Corregidor and employed it throughout their tenure in Melbourne.
Central Bureau moved to a new location at 45 Eldernall Avenue, Hamilton sometime later.
Japanese POW's were interrogated at a house called "Tighnabruaich" at Indooroopilly
Indooroopilly, Queensland
Indooroopilly is a suburb of Brisbane, Australia which is located 7 km west of the Brisbane central business district.- Name derivation and history :...
in Brisbane.
Central Bureau at 21 Henry Street, Ascot in Brisbane decrypted a Japanese Army Air/Ground signal intercepted by 51 Wireless Section in Darwin
Darwin, Northern Territory
Darwin is the capital city of the Northern Territory, Australia. Situated on the Timor Sea, Darwin has a population of 127,500, making it by far the largest and most populated city in the sparsely populated Northern Territory, but the least populous of all Australia's capital cities...
that contained Admiral Isoroku Yamamoto's itinerary for an upcoming trip to Rabaul
Rabaul
Rabaul is a township in East New Britain province, Papua New Guinea. The town was the provincial capital and most important settlement in the province until it was destroyed in 1994 by falling ash of a volcanic eruption. During the eruption, ash was sent thousands of metres into the air and the...
. Admiral Yamamoto, was the Commander in Chief of the Combined Japanese Fleet, the architect of the attack on Pearl Harbor
Pearl Harbor
Pearl Harbor, known to Hawaiians as Puuloa, is a lagoon harbor on the island of Oahu, Hawaii, west of Honolulu. Much of the harbor and surrounding lands is a United States Navy deep-water naval base. It is also the headquarters of the U.S. Pacific Fleet...
. Central Bureau reportedly sent the decrypted message to FRUMEL where it was reportedly translated by a U.S. Navy linguist. Although Central Bureau may have decrypted the message, the interception of his flight was based on decrypts of Japanese naval messages by FRUPAC/Station HYPO in Hawaii, FRUMEL, OP-20-G in Washington and Station AL on Guadalcanal. Major Lasswell USMC in Hawaii decrypted the Japanese Naval message first and Captain Layton (Pacific Fleet Intelligence in Hawaii) gave it to Admiral Nimitz who authorized a shootdown attempt after determining from ComNavAirSoPac that it could be done with by one of his Army Air Corp units on Guadalcanal.
Central Bureau is probably the precursor to the Defence Signals Directorate
Defence Signals Directorate
Defence Signals Directorate is an Australian government intelligence agency responsible for signals intelligence and information security .-Overview:According to its website, DSD has two principal functions:...
.