Operation Transom

Operation Transom was an attack made by Allied forces against the Japanese-held city of Surabaya on 17 May 1944 during World War II. It was conducted by the British-led Eastern Fleet, and involved aircraft launched from American and British aircraft carriers striking the city's docks and an oil refinery. One American torpedo bomber was shot down.

Operation Transom
Part of the South-East Asian theatre of World War II
Surabaya during the attack by Allied carrier aircraft
Date 17 May 1944 Location Surabaya, Dutch East Indies 7.211035°S 112.730260°E Result Allied victory
Belligerents
United Kingdom  United States  Australia  New Zealand  Netherlands  France	Japan
Commanders and leaders
James Somerville
Strength
76 aircraft 2 aircraft carriers 3 battleships 1 battlecruiser 6 cruisers 14 destroyers	Anti-aircraft batteries
Casualties and losses
1 aircraft destroyed	Accounts differ

The attack on Surabaya was the second, and final, joint American-British aircraft carrier raid in the Indian Ocean during 1944. It was undertaken as a diversion from an Allied landing on an island off New Guinea on the same day, and to make use of the American aircraft carrier on its return voyage to the Pacific. Estimates of the extent of the damage inflicted by the Allies differ between sources; some describe the results as modest while others state that they were significant. There is consensus that the operation provided the British Royal Navy with useful exposure to superior United States Navy carrier tactics. The attack had no effect on Japanese military deployments.

Background

Japanese forces invaded and conquered most of the Dutch East Indies between December 1941 and March 1942. The island of Java was administered by the Imperial Japanese Army during the Japanese occupation of the Dutch East Indies.[1] Surabaya, which is located in eastern Java, was a naval base and industrial centre during the occupation. Japanese anti-submarine forces based at Surabaya hunted Allied submarines operating in the Java Sea.[2] The Wonokromo oil refinery was important to the Japanese, and was the only facility in Java which produced aviation fuel.[2][3] The city's defences against air attack at the time of Operation Transom included a small number of anti-aircraft guns, whose crews were inadequately trained.[4]

Admiral James Somerville addressing the crew of USS Saratoga on 3 April 1944

At the Cairo Conference held during November 1943, the Allied leadership agreed that "the main effort against Japan should be made in the Pacific", and that the Indian Ocean would be a subsidiary theatre. It was also decided that any offensive operations, including aircraft carrier raids, in the theatre would have the goals of "maintaining pressure on the enemy, forcing dispersion of his forces, and attaining the maximum attrition of his air and naval forces and shipping".[5]

The British Eastern Fleet, which was led by Admiral James Somerville and based in Ceylon, was heavily reinforced during early 1944. The aircraft carrier HMS Illustrious, battleships HMS Queen Elizabeth and Valiant and battlecruiser HMS Renown arrived in January, providing the fleet with an offensive capability. Many other ships arrived over the course of the year.[6]

Also in early 1944, the Japanese military transferred its main naval striking force, the Combined Fleet, to Singapore. This change was made to evacuate the fleet from its bases in the central Pacific, which were now vulnerable to American attacks, and concentrate it at a location with good naval repair facilities and ready access to fuel. The Japanese did not intend to undertake any large-scale attacks into the Indian Ocean. Somerville believed that his force would be unable to counter the Combined Fleet if it entered the Indian Ocean, and additional air units were dispatched to protect Ceylon.[7] The United States Navy also agreed to temporarily transfer the aircraft carrier USS Saratoga and three destroyers from the Pacific to augment the Eastern Fleet.[8]

Saratoga and her escorts joined the Eastern Fleet on 27 March 1944.[9] Illustrious and Saratoga, accompanied by much of the Eastern Fleet, conducted a successful air raid against the Japanese-held island of Sabang in the Dutch East Indies on 19 April as part of Operation Cockpit.[10]

Prelude

Following Operation Cockpit, Saratoga was directed to return to the United States for a refit.[11] The head of the US Navy, Admiral Ernest King, suggested to Admiral Louis Mountbatten, the commander of South East Asia Command that the carrier, accompanied by other vessels of the Eastern Fleet, strike Surabaya on her return voyage. King hoped that this would act as a diversion from the planned Allied landing at Wakde Island off New Guinea. Mountbatten agreed to this proposal.[12]

Somerville decided to conduct the attack using almost the same forces as had been involved in Operation Cockpit.[11] One of the main differences was to substitute Grumman Avengers for Illustrious's usual air wing of Fairey Barracuda torpedo and dive bombers. This change was made as Somerville expected the Japanese to more strongly defend Surabaya than they had Sabang, and had decided to launch the aircraft 180 miles (290 km) from the city which was beyond the Barracuda's effective range.[13] Due to the distance to be covered from Ceylon and the Royal Navy's lack of experience in underway replenishment, the final plans for the operation involved the Eastern Fleet refuelling at Exmouth Gulf in Western Australia before striking Surabaya.[2]

The Eastern Fleet was organised into three forces for Operation Transom. Force 65 comprised one French and two British battleships, a British battlecruiser, two cruisers and eight destroyers, of which four were Australian. Force 66 was made up of Illustrious, Saratoga, two cruisers and six destroyers. Force 67 was the replenishment group, and comprised six tankers, a water distilling ship and two cruisers. Somerville commanded the fleet from Queen Elizabeth. The Australian light cruiser HMAS Adelaide was also to proceed from Fremantle in Western Australia to protect the tankers while they remained at Exmouth Gulf during the attack; this allowed their two escorting cruisers to augment Force 66.[14]

Attack

An Avenger being loaded with bombs on board HMS Illustrious prior to the raid on Surabaya

Force 67 was the first element of the Eastern Fleet to sail, departing on 30 April. Forces 65 and 66 sailed on 6 May. The Allied ships proceeded to Exmouth Gulf on a course which kept them at least 600 miles (970 km) from Japanese airfields. They arrived at Exmouth Gulf on 14 and 15 May. While his ships were refuelling, Somerville met with the commander of the United States Seventh Fleet, Admiral Thomas C. Kinkaid, Rear Admiral Ralph Waldo Christie who commanded the fleet's submarines, and the Naval Officer In Charge Fremantle, Commodore Cuthbert Pope, to discuss the most recent intelligence.[15]

The Eastern Fleet departed Exmouth Gulf on the afternoon of 15 May and proceeded north. It arrived at the flying off point at 6:30 am local time on 17 May without being detected by the Japanese.[3] One British and seven American submarines also took up positions near the southern entrance to the Strait of Malacca and the Bali, Lombok and Sunda Straits to support the Eastern Fleet; the boats were tasked with attacking Japanese warships and rescuing downed Allied pilots.[16][17]

The aircraft launched by the carriers were organised into two strike forces. Force A was made up of nine Avengers from Illustrious, twelve Douglas SBD Dauntless dive bombers from Saratoga and an escort of eight Vought F4U Corsair fighters from the British carrier. It was tasked with attacking the oil refinery and other industrial facilities in the Wonokromo area. Force B was to attack shipping and dock facilities in Surabaya's port. It comprised twenty-one Avengers and six Dauntlesses escorted by eight British Corsairs and twelve American Grumman F6F Hellcats.[18] All of the aircraft were launched and formed up with the rest of their force by 7:20 am.[3]

The attack on Surabaya commenced at 8:30 am. The Japanese had not detected the aircraft as they approached, and were taken by surprise.[3] The two forces made a well synchronised attack, with Force A approaching Wonokromo from the south and Force B attacking the port from the north. No Japanese fighter aircraft were encountered, and the anti-aircraft guns were largely ineffective. One of Saratoga's Avengers was shot down.[4] The Allied pilots believed that they had inflicted heavy damage.[3]

After the strike force completed landing on the carriers at 10:50 am, the Eastern Fleet withdrew to the south-west in an attempt to obscure the fact that it was headed for Exmouth Gulf.[4][16] Somerville's staff had not requested a debriefing from the American strike leader upon his return. As a result, they were unaware that many worthwhile targets, including Japanese submarines, remained in Surabaya's port until 3 pm when photographs taken by one of Saratoga's photo reconnaissance aircraft were dropped onto Queen Elizabeth. Somerville later regretted not ordering a second strike during the afternoon of 17 May.[4][19]

On the night of 17/18 May Allied heavy bombers based near Darwin in northern Australia struck Surabaya.[16]

Aftermath

Saratoga and her three escorting American destroyers detached from the Eastern Fleet shortly before sunset on 18 March, and proceeded to Fremantle. The remainder of the Eastern Fleet reached Exmouth Gulf the next morning, and sailed for Ceylon before sunset after refuelling again.[16] It arrived back at Ceylon on 27 May.[20]

Saratoga's crew farewelling Illustrious on 18 May 1944

Accounts of the damage inflicted during Operation Transom differ. Writing in 1960, the official historian of the Royal Navy's role in World War II Stephen Roskill stated that the Allied pilots had over-estimated the damage caused, as Japanese records "do not confirm that either their shipping or the shore facilities suffered at all heavily" and indicate that only a single small ship was sunk.[3] The Australian naval official historian G. Hermon Gill reached an identical conclusion in 1968. He also noted that Admiral Guy Royle, the head of the Royal Australian Navy, told the Australian Advisory War Council on 23 May that operation Transom had been of dubious value on military grounds as similar results could have been achieved by land-based aircraft without a need to risk warships to attack.[21] In contrast, the official historian of the British effort in South East Asia Stanley Woodburn Kirby wrote in 1962 that the Wonokromo oil refinery and other industrial facilities were set on fire, the naval dockyard and two other docks were bombed and twelve Japanese aircraft destroyed on the ground.[22] More recently, historian Jürgen Rohwer stated in 2005 that twelve Japanese aircraft were destroyed on the ground, a small freighter was sunk and a patrol boat damaged beyond repair.[23] In 2011 David Hobbs judged that the operation was successful, with the Wonokromo oil refinery being "burnt out", naval dock installations damaged and a merchant ship sunk.[24] Marcus Faulkner wrote in 2012 that Operation Transom "inflicted considerable damage".[20]

Both Roskill and Hobbs agree that the attack provided the Royal Navy with important experience of carrier strike operations and exposure to superior American carrier tactics. Roskill observed that Somerville decided to copy the way in which Saratoga's crew conducted flight operations.[25] Hobbs identifies a number of other lessons the Royal Navy took away from the operation, including the need to plan to conduct at least two strikes against targets and the desirability of obtaining photo reconnaissance aircraft which could be flown from carriers.[26]

As was also the case with Operation Cockpit and the several other carrier raids the Eastern Fleet conducted in 1944, Operation Transom did not have any effect on Japanese deployments.[27][28] This was because the Combined Fleet did not regard the Eastern Fleet as a threat, and was under orders to preserve its strength to contest a major American offensive which was expected to take place in the central Pacific.[29]

References

Citations

1. Dear & Foot 2001, p. 613.
2. Hobbs 2011, p. 42.
3. Roskill 1960, p. 357.
4. Hobbs 2011, p. 45.
5. Roskill 1960, p. 346.
6. Roskill 1960, p. 347.
7. Roskill 1960, pp. 347–348.
8. Roskill 1960, p. 348.
9. Roskill 1960, p. 354.
10. Kirby 1962, pp. 380–381.
11. Roskill 1960, p. 356.
12. Gill 1968, p. 416.
13. Roskill 1960, pp. 356–357.
14. Gill 1968, pp. 416–417.
15. Gill 1968, p. 417.
16. Gill 1968, p. 419.
17. Hobbs 2011, p. 41.
18. Hobbs 2011, pp. 42, 45.
19. Roskill 1960, pp. 357–358.
20. Faulkner 2012, p. 224.
21. Gill 1968, pp. 418–419.
22. Kirby 1962, p. 382.
23. Rohwer 2005, p. 323.
24. Hobbs 2011, p. 46.
25. Roskill 1960, p. 358.
26. Hobbs 2011, pp. 45–46.
27. Kirby 1962, p. 384.
28. Faulkner 2012, p. 221.
29. Roskill 1960, p. 355.

Works consulted

• Dear, I.C.B.; Foot, M.R.D., eds. (2001) [1995]. The Oxford Companion to World War II. Oxford: Oxford University Press. ISBN 9780198604464.
• Faulkner, Marcus (2012). War at Sea: A Naval Atlas, 1939–1945. Annapolis, Maryland: Naval Institute Press. ISBN 9781591145608.
• Gill, G. Hermon (1968). Royal Australian Navy, 1942–1945. Australia in the War of 1939–1945. Series 2 – Navy. Volume II. Canberra: Australian War Memorial. OCLC 65475.
• Hobbs, David (2011). The British Pacific Fleet: The Royal Navy's Most Powerful Strike Force. Annapolis, Maryland: Naval Institute Press. ISBN 9781591140443.
• Kirby, S. Woodburn (1962). The War against Japan. History of the Second World War. Volume III: The Decisive Battles. London: HMSO. OCLC 632441219.
• Rohwer, Jürgen (2005). Chronology of the War at Sea: 1939–1945: The Naval History of World War Two (Third revised ed.). Annapolis, Maryland: Naval Institute Press. ISBN 1591141192.
• Roskill, S.W. (1960). The War at Sea 1939–1945. Volume III: The Offensive Part I. History of the Second World War. London: Her Majesty's Stationery Office. OCLC 58588186.