SEABORNE COMMUNICATION UNIT
AND MOBILE COMMUNICATION UNIT
IN THE SOUTHWEST PACIFIC AREA
DURING WWII

In the early years of the war in the Southwest Pacific Area the US Army Signal Corps utilised small boats mainly small schooners fitted with manual keyed, medium powere CW radio equipment plus small portable sets for ship to shore operation.

In the spring of 1944, Seaborne Communications was born, but was not officially authorized before January of 1945. In the post years of the war, many vessels of various types were pressed into service, such as the FP47 Communication Boat. The purpose of these floating Signal Centres was:-

• to provide communications during assault phases

• to provide communications during the period that fixed facilities were being set up ashore

• to function as standby or emergency facilities in case of difficulty ashore

The immediate plan was to have invasion vessels and floating Army Command and Administrative Network ACAN stations on the spot right after a landing was secured. At this point in time a GHQ major radio communication station, so close to the action, was unheard of. Brigadier General Spencer Ball Akin obtained three ships to be under Army control - NOT Navy - but manned by the Navy. These three ships would be outfitted for the invasion of Leyte in the Philippines all equipped with Army Signal Corp units. The Seaborne Signal Corps echelon obtained:-

• three US Navy vessels which were known as Patrol Craft Escorts (Rescue) PCE (R) 848, PCE (R) 849, and PCE (R) 850

• a former revenue cutter / schooner "Apache"

• a private yacht (1890 vintage)

• a boat originally constructed from combined passenger and freight traffic in Alaskan waters FP-47

Three PCE (R)s

The three PCE (R) craft had their former large hospital area equipped with two AT / 20 Transmitters an Australian manufactured set rated at 500 watts. The Radio Receivers that were used were a mixture of Navy type shielded receivers, Super Pros and AMR 100s which was an Australian version of the HRO. This enabled operation of two CW manual radio circuits from each ship and provided extra receivers for intercept and monitoring. AN / TRC-3s with Teletype and telephone channels were also installed for ship-shore and Ship-ship communications. Additionally SCR-300s and SCR-284s were placed on board for miscellaneous uses as required. These small sets were frequently used for communication between ship and shore or reconnaissance parties and provided invaluable initial communication contact. Appropriate cryptographic equipment was also utilised.

The PCE (R) 848 went into the invasion with Brig. Gen. Akin aboard. PCE (R) 849 was backup for PCE (R) 848 and had Brig. Gen. Akin's deputy aboard. PCE (R) 850 had the 6th Army Signal Corp aboard.

"S.S. APACHE"

The 50-year-old schooner, "Apache" which had many uses, was formerly President McKinley's yacht. The yacht was outfitted in Sydney, Australia with necessary gear. The good old faithful COMM. FP-47 was its backup. The "Apache" was mainly intended to be used as a Broadcast ship and it was equipped with a 10KW Amalgamated Wireless of Australia AWA transmitter. Power units were also included so that the transmitter was independent of the ship's power. A modern broadcast studio with recording equipment and a control room were installed. "Apache" was also provided with VHF, telephone and Teletype equipment as well as SCR-300s and SCR-284s.

FP-47

The FP-47 was was used as a Press Ship for use by War Correspondents and was initially equipped for CW operation but was later converted to high speed Boehme equipment. Australian made AT/20 transmitters were also installed.

Three LCMs

Three LCM's furnished by the US Navy had mobile communications equipment aboard to establish land terminals.

Ocean Lighters and a Paddle Steamer!!

For the construction of the floating ACAN stations, 7 ocean lighters (OL's) which were more or less barges, were ordered from a Sydney, Australia shipyard. They were 120' long with a 24' beam. They were new and were originally intended to carry cargo.

NARA Photo:-  SWPA-SC-44-6656

Ocean Lighter OL-3 at Walsh Bay, Sydney on 29 April 1944

Usage of the Ocean Lighters was as follows:-

By deduction I believe the Ocean Lighters were assigned as follows:-

OL-22    Receiver
OL-23    Receiver
OL-29    Transmitter
OL-30    Transmitter
OL-31    Sigsaly

All the barges were fitted with AM/TRC-3 radio link equipment of communication between barges as well as radio keying and control lines. Terminal frames were provided so that cable and wire links to other barges and to shore could be easily connected. Each barge contained two each 50KW Diesel power units, modified with heat exchangers for salt water cooling.

NARA Photo:- SWPA-SC-44-9875

OL-22 midships, looking starboard, showing position
of Teletype Test Unit. Brisbane 17 October 1944

NARA Photos:- SWPA-SC-44-9884

OL-22 Starboard side, looking forward, showing 96-C Antenna
connections and cable runs. Brisbane 17 October 1944

NARA Photo:- SWPA-SC-44-9887

OL-28 aft, looking forward and starboard, showing
manual positions. Brisbane 17 October 1944.

The original plan called for 3 ACAN stations, using 6 of the OL's. The 7th, OL31, was equipped with a SIGSALY terminal at Bulimba in Brisbane. The first station consisted of OL22 receiver and OL30 transmitter.

Approximately seventy-five Army personnel were transferred to Seaborne to accomplish the task. In October of 1944, the OL22 and OL30 proceeded to Hollandia, Dutch New Guinea, and set in and handled traffic there for a few months, then moved on to Manila Bay in the Philippines. In early June 1945, OL23 receiver and OL29 transmitter arrived. George Sullivan could not locate any information on the other two OL's. He believed it was possible that they became Signal Corp supply and repair boats.

A support vessel for the Ocean Lighters was an Australian wooden paddle wheel steamer "Weeroona" (1910) which had previously been used for Australian coastal passenger traffic from Melbourne to Queenscliff. "Weeroona" was the last of the Port Philip Bay paddle steamers to be built. She was built by A. S. Inglis of Glasgow in 1910 for Hubbart Parker and Company. "Weeroona" took 70 days to complete her maiden voyage from Glasgow to Melbourne via the Suez Canal, Jakarta, Thursday Island, Brisbane and Sydney.

"Weeroona" serviced the resorts of Port Philip Bay until 1942 when she was purchased by the US Navy who intended to refit her as a convalescent and accommodation ship. Leaving Melbourne in 1943, "Weeroona" travelled under her own steam to Sydney and then she was taken under tow to the Philippines via Brisbane and New Guinea.

Larger than the other two paddle steamers, "Weeroona" was 310 feet long (95 metres), constructed of steel, weighed 1412 tons and licensed to carry 1900 passengers. Again she was extremely luxurious with spacious promenade decks and impressive lounges and dining rooms.

Paddle Steamer "Weeroona"

Photo:- AWM Photo ID Number: P04853.048

"Weeroona" (S-195) in Sydney in 1943

The paddle wheel steamer was fitted out as quarters for the men required to operate and maintain the communications equipment on the Ocean Lighters. Five high bunks were installed on the main deck with canvas to protect the men from the elements. The crew provided by the Transportation Corps to maintain and handle the Ocean Lighters had their quarters on board their individual ocean lighter. The Ocean Lighters and "Weeroona" were all relocated to new positions by being towed.

In September 1944, "Weeroona" came to Brisbane to be the quarters ship for the technical members of four ships. Two of the ships were for transmitting to the U.S. and other Theaters. The four ships furnished communications to San Francisco, then to Washington D.C. for General Douglas MacArthur and his Headquarters at Hollandia and Manila.

On 24 September 1944, Henry W. Flora was transferred from Hemmant Transmitting Station to Seaborne Communications at Bulimba on the Brisbane River. His first glimpse of his assignment was of two Ocean Lighters (OL) of which he became the Officer in Charge.

At that time they were no longer marine ships as all marine propulsion gear had been removed. They were essentially going to house Radio Transmitters. There was just open space below deck. Their job was to install new 40K and D156000 SSB Transmitters plus other smaller Transmitters. Hemmant Transmitting Station continued to operate. They were in effect to be a floating version of the Hemmant Transmitting Station. In addition there were two other OLs that were to have Receiving equipment installed under the supervision of Lt. Murray Hannah. It was indeed a challenging job to make such an installation in an iron cage. All cables were covered with lead. All equipment had to be anchored to the deck. Work went on night and day under lights. Dipole antennas were installed regardless of proper impedance matching. When the Radio was operating the masts were extended to twice their usual heights. On 1 November 1944 with a complete and operable installation, they moved on to Hollandia to merge with the moving of General Douglas MacArthur's GHQ SWPA there. Seaborne came into Manila harbor while some fighting was going on. After three days Seaborne was in operation for General MacArthur's Headquarters. The army land transmitters and receiving sites taken over by the Japanese when the Philippines was captured were restored for use. During the period of time from when Seaborne arrived, and land communication were established, until the war end in August 1945, both Seaborne and the land station communicated with San Francisco and thereby Washington. When the fighting finished in the Philippines, Seaborne stopped transmitting to San Francisco and began preparing to support General MacArthur on the invasion of Japan. At that time 1st Lt. Henry W. Flora was transferred to the land station and was charged with the successful operation of the two D156000 SSB transmitters. 1st Lt Henry W. Flora boarded a troop ship head for the United States in November 1945 to be reunited with his wife and son.

In addition to the OL Number they simply referred to the barges as T1, T2 and R1, R2. T1 contained the 40K and SSB. T2 Motor Generators. The T boats were towed in tandem by a Navy Tug, likewise R boats. On Army personnel on each boat, Henry W. Flora asked for a volunteer for that assignment. The ships had no amenities. The rest of the men went by troop ship to Hollandia. Lt. Murray Hannah and Henry W. Flora were the only Army people to stay with the Weeroona and its Australian crew. The Weeroona stopped briefly at Milne Bay on the way to Hollandia.

Photo:- Henry W. Flora

1st Lt. Henry W. Flora working on board
either OL29 or OL-30 Transmitter Ship

"Weeroona" was to have her coal fired boilers replaced by oil fired boilers but time ran out and she too had to be towed. There was no luxury for the men by the time she was refitted. The U.S. Army contracted with the Australian Government for a crew including cooks, etc. When they were on location they lived on the "Weeroona" when operating the communications ships. Henry W. Flora had three Lieutenants reporting to him and the communication operated 24/7. The "Weeroona" in Manila was docked along a break water near the Manila Hotel. Henry W. Flora was a friend of one of the Australian crew, First Mate Gunn. The city of Manila lay in ruins, with many sunken ships in the harbor.

Henry W. Flora told me that the unused steam engine for the "Weeroona" was a sight to behold, two huge pistons and connecting rods about 20 ft long. Murray Hannah was in charge of the Receiving ships. Henry W. Flora and Murray Hannah became good friends and were still in touch in December 2017 with Murray aged 100 and Henry turning 100 in February 2018.

The Australian Government purchased Weeroona from the US Navy in 1945 and sold her for scrap in 1951 when she was stripped and sunk off Berry Bay in NSW.

Mobile Communication Unit

A Mobile Communication Unit was formed to work in conjunction with the Seaborne Communication Unit to facilitate easily established highly mobile communication facilities in a minimum time. It also served on a temporary basis until such time as fixed semi-permanent facilities could be established under suitable cover.

The Mobile Communication Unit used for the Leyte landings was smaller than that used for the Luzon operations but the type of equipment and service provided were similar. The following equipment was used by the Mobile Communication Unit in the Luzon operation which included the landings at Lingayen Gulf:-

34 off 2.5 ton 6 x 6 WD trucks

Two Each 6 Ton Vans

Two Each Four Ton Prime Movers

28 Each One Ton, Two Wheel Trailers

Two Each Special 4-Wheel Trailers

Twenty Jeeps

Twelve Miscellaneous Vehicles

Leyte Operation

When Gen. MacArthur landed in Australia, he made a promise to the people of the Philippines, "I shall return". He specified that he wanted a radio broadcast ship in the convoy so that when he stepped ashore in the Philippines - which was 3 hours after the invasion started - he could broadcast that message to the people. It was also going to be used to broadcast to the guerrillas, plus press service to the world.

The combined and co-ordinated efforts of the Seaborne and Mobile Communication Units in the Leyte operation were very successful. General MacArthur was transported to Leyte on board the cruiser "USS NASHVILLE". Whilst communication silence was maintained during the voyage, a small detachment of Signal Corps personnel were able to get message to MacArthur by Naval "Fox" broadcasts. They used special cryptographic equipment for handling the Genera's traffic as well as a Willcox 96-C transmitter and VHF - carrier equipment.

Once communication silence was lifted at 1000 hours, communication by AN/TRC-1 and CW manual radio was established between USS NASHVILLE and vessels of the Signal Corps Seaborne Fleet. The APACHE sent out General Douglas MacArthur's communique which began with the words:-

"In a major amphibious operation we have seized the Eastern Coast of Leyte Island in the Philippines."

At 1400 hours a truck of the Mobile Communication Unit equipped with a VHF Radio Terminal and miscellaneous equipment rolled ashore from a landing barge. Within 15 minutes they had established contact with USS NASHVILLE and APACHE. Shortly after this General Douglas MacArthur waded ashore and after an inspection of the beachead he walked over to the communications truck and spoke those famous words into a waiting microphone:-

"I have returned. By the grace of Almighty God our forces stand again on Philippine soil - soil consecrated in the blood of our two peoples."

His words were relayed to USS NASHVILLE and broadcast to the people of the Philippines and later were broadcast by both APACHE and USS NASHVILLE and by pre-arrangement were received by stations in California and Australia for rebroadcast throughout the world.

The rest of the Mobile Communication Unit went ashore and setup the communications for MacArthur's new Advanced General Headquarters. Construction of new communication facilities at Leyte was slowed down by the rain, and muddy conditions. The Luzon operation was underway before permanent installations were completed at Leyte.

Intercept Section

The Intercept Section in the Mobile Communication Unit was equipped with radio receivers and cryptographic equipment to intercept and decode traffic on pre-selected circuits of their own forces. After being decoded and screened this traffic was distributed to appropriate Staff sections in Advanced GHQ SWPA. This made it possible for staff officers to maintain a running and current account of selected tactical units.

The Intercept Section had been started in Port Moresby and was used throughout the northward advance. The Intercept Section used a large six-ton van with receivers mounted at operating positions. The six-ton van proved impractical in the Philippines due to the poor roads and extreme muddy conditions.

Japanese Air Raids

On 25 October 1944 four Japanese bombers made one of many raids over Leyte Gulf. One of the PCE (R) boats was hit by fragments of a Japanese bomb. The ships gunners managed to shoot down the bomber which hit the water about 1,000 yards off the port bow. The bomb fragments pierced the first superstructure deck entering the Captain's cabin and wardroom. Two crew members were killed and 10 others were wounded. Signal Corps members were not amongst the dead or injured.

On 28 October 1944 another one of the PCE (R)'s was straddled by three Japanese bombs, with the nearest hitting about 20 yards away. Bomb fragments put about 80 holes in the starboard side and 20 holes on the port side of the ship. Six crew members were killed and 25 including the Captain were wounded. Some communications equipment was damaged but the ship continued to operate until it was sent to a rear area for repair and re-equipping.

"Voice of Freedom"

Whilst at Leyte, APACHE sent out a daily 30 minute broadcast to the Philippines known as the "Voice of Freedom". When APACHE needed to move forward and maintain radio silence, a Wilcox 96-C transmitter was set up ashore to facilitate the daily broadcasts.

Luzon Operations

By Christmas Day 1944, most of the major preparations for the Luzon operation were completed. the Mobile Communication Unit started to load their equipment on to LST's and other boats. Portions of the Mobile Unit joined the Seaborne Unit for the trip to Luzon to take part in the early landings. Another portion of the Mobile Unit accompanied the assault troops so they could be placed ashore early in the landings.

APACHE experienced some engine problems enroute and had to be towed for a short while. Once it was determined that the issue was water in the fuel supply, they used fuel from the Signal Corps tanks on board to get underway again allowing APACHE to arrive off Lingayen with the rest of the convoy.

Once communication silence was lifted, the Seaborne Signal Corps Fleet went on the air and was soon working solidly with channels to Leyte and ship to ship circuits. The FP-47 operated a Boehme circuit back to Leyte where commercial press facilities were available back to the USA.  The APACHE commenced its broadcast routine again and before too many hours the news of the landings had been spread around the world.

The day after the landings the first trucks of the Mobile Unit went ashore on White Beach, near the town of San Fabian. The trucks were equipped with VHF terminals and they were also carrying SCR-300's for miscellaneous communication. Within an hour the trucks were in communications with elements of the Seaborne Unit and also with the Cruiser USS BOISE which had taken General Douglas MacArthur to the operation. These first trucks of the Mobile Unit  reconnoitered suitable sites to set up the remainder of the Mobile Unit equipment and to select road approaches and to provide communications for General MacArthur whilst he was ashore and for other members of his staff.

MacArthur established an Advanced Echelon of GHQ at the town of Dagupan. The rest of the Mobile Unit came ashore over the next two days. With road and bridge problems a good portion of the Mobile Unit came under Japanese fire on the beach while critically needed trucks were moved into Dagupan on LCM's.

A TC/2 switchboard for MacArthur's Advanced Echelon GHQ was established from a truck and later replaced by a TC/10. CW contact with San Francisco, using a BC 3339 transmitter (1 KW) was soon in service and circuits back to Leyte and other units in the area quickly established. A Signal Centre was established in an old two story building across from the market place in Dagupan. A semi-permanent installation was operating within five days of arriving in the town.

The men and equipment of the Mobile Communication Unit continued to support General Douglas MacArthur on his push forward to Manila.

Signal Corps "Mariners" sail into Manila Bay

The six steel ocean going lighters of the Signal Corps Seaborne Communications Unit were towed from Hollandia accompanied by a wooden paddle wheel steamer. They sailed into Manila Bay past Corregidor. They were dubbed, "Gen. Akin's Grand Fleet."

Japanese Surrender

At about 0900 hours Manila time, on 15 August 1945, a routine Teletype Conference in the Signal Center in the former Manila Water Works building was underway with "WAR", which was the Teletype Conference Room in the Pentagon, Washington D.C. The conference was interrupted and Manila was advised to stand by to receive an important message. The following message was received:-

"NR 1408 WITH REFERENCE TO PARAGRAPH TWO OF WARX FOUR NINE ONE EIGHT TWO CMA PAREN FROM MARSHALL TO MACARTHUR CMA INFO NIMITZ DEANE AND WEDEMYRE PAREN YOU ARE HEREBY OFFICIALLY NOTIFIED OF JAPANESE CAPITULATION PD YOUR DIRECTIVE AS SUPREME COMMANDER FOR THE ALLIED POWERS IS EFFECTIVE WITH RECEIPT OF THIS MESSAGE."

REFERENCES

SO. WEST PACIFIC, U.S.A. Sig. Corps. 1941 - WWII - 1945 "As I Recall" - Book 1.
by George J. Sullivan

ACKNOWLEDGEMENTS

I'd like to thank Laurie Murray and Henry W. Flora for their assistance with this web page.

Can anyone help me with more information?

"Australia @ War" WWII Research Products

This page first produced 10 February 2017

This page last updated 10 February 2020