The British received warning of the raid through decoded Japanese wireless messages in March 1942 and from air reconnaissance during the Indian Ocean raid. The British forestalled the Japanese Navy by dispersing shipping from the harbours in Ceylon before the attacks. The Japanese aircraft were met by fighters of 222 Group, Royal Air Force, the Fleet Air Arm (FAA) of the Royal Navy and anti-aircraft guns.
Port facilities were damaged and ships in harbour were sunk or damaged. The bulk of the Eastern Fleet was not found and survived but several ships were sunk after the raid on Ceylon. The Eastern Fleet moved temporarily to East Africa, from where it sent carrier forces into the central and eastern Indian Ocean. The Japanese Navy was unable to repeat the raid because of its commitments in the Pacific.
Ceylon (now Sri Lanka) is off the south-east of India between shipping routes from Singapore and Rangoon to the Red Sea and the Persian Gulf. There are natural harbours at Colombo on the south-western coast and Trincomalee on the north-eastern coast, a naval anchorage and base.[2] Ceylon was a geographically important part of the British Empire and its system of trade, communication and military organisation. In the 1930s more shipping tonnage was handled in Ceylon than all the ports of India. Since the beginning of the Second World War, the colonial government had engaged in mass recruitment for local defence, overseas labouring and expanded food production.[3] Tea and rubber production was emphasised and rubber output rose from 99,500 long tons (101,100t) in 1941 to 105,500 long tons (107,200t) in 1943.[4] The 3,600 workers in civil engineering converted to the repair and refitting of ships and the manufacture of dummy aircraft, guns and radar installations.[3]
When the Pacific War began on 7 December 1941, the Allied disasters in the Pacific, Malaya and the British débâcle at the Battle of Singapore in February 1942 made Colombo Harbour the basis for eastern trade and the centre for the assembly of Indian Ocean convoys. Colombo port was large enough for 45 ships but soon had 100 to 110 ships at once, causing much overcrowding.[5] The strategic importance of Ceylon increased and British planners deemed the island essential to the defence of India and Allied lines of communication through the Indian Ocean. The Allied defeat in the Dutch East Indies campaign (11 January – 9 March 1942) left the Indian Ocean vulnerable to Japanese attacks.[6] The Malacca Strait in the Netherlands East Indies was about 1,000nmi (1,900km; 1,200mi) east of Trincomalee, making it a useful base for attacks on Japanese ships sailing to Rangoon in Burma.[2]
From September to December 1941, 710 troop reinforcements arrived on the island and from January to March 1942, another 2,612 arrived; during April and June, 2,112 more troops joined the garrison (2,872) and 4,993 troops moved between the Far East and Ceylon from October 1941 to March 1942.[7] The extent of the disasters that befell the British in early 1942, led in March to Admiral Sir Geoffrey Layton being installed as the Commander-in-Chief, Ceylon, with authority over the military forces on the island and the civilian governor, Sir Andrew Caldecott, "Do not ask permission to do things. Do them and report afterwards what you have done".[8] Layton found the same complacency and inertia in Ceylon as he had experienced in Malaya,
...he takes complete charge of Ceylon and stands no nonsense from anyone.... He pulls all the Ministers legs... and they work for him all the harder.
By March 1942, airfields existed at China Bay near Trincomalee, Ratmalana near Colombo, an airstrip was built at the Colombo Racecourse to relieve congestion at Ratmalana and another airstrip had been built at Minneriya on the south coast. China Bay was a grass landing ground that had the sea at both ends and there was a ridge along the southern edge; a low ridge ran along the northern boundary. Aircraft could only land and take off to the north-east or south-west, depending on the wind direction. There were fuel storage tanks beyond the north-east corner of the airfield at the Royal Naval Base Trincomalee.[2] Anti-aircraft defence comprised four obsolescent QF 3-inch 20 cwtanti-aircraft guns at Trincomalee. The danger of an air attack by aircraft of the Japanese Navy aircraft carriers was acute after the examples of the Attack on Pearl Harbor in December 1941 and the Bombing of Darwin in February 1942.[1] The airfields at Ratmalana, near Colombo and China Bay had been expanded.[11][a]
Example of a Catalina flying boat
On 6 and 7 March the aircraft carrier HMSIndomitable dispatched sixty Hurricanes of 30 Squadron and 261 Squadron, that had been intended for Java. On 30 March, the RAF reconstituted 258 Squadron that had been mauled in the fighting in British Malaya, Sumatra and Java.[13] By 4 April, 803 NAS and 806 NAS of the Fleet Air Arm were ready with 24 Fulmars; the ground defences had been reinforced to 144 anti-aircraft guns. On 5 April, there were 37–38 serviceable Hurricanes near Colombo.[14]
The first Consolidated PBY Catalina long-range flying boat of 413 SquadronRoyal Canadian Air Force (RCAF) arrived on 28 March, with the ground crews following on by sea, two more arrived before the raid and on 6 and 7 April two more Canadian Catalinas arrived.[15] By 4 April, four 205 Squadron RAF Caalinas had reached the island. There was one operational Dutch Catalina of the Netherlands Naval Aviation Service (MLD); two of the RAF and three Dutch Catalinas were unserviceable. The Catalinas were based at Koggalalagoon, at the south end of the island.[12]
Radar
Radar stations, code-named Air Ministry Experimental Stations (AMES) were established at Colombo (AMES 254) whose personnel arrived on 18 March and its equipment four days later. The station became operational at the Royal Colombo Golf Club (about 6mi (9.7km) north of Ratmalana) on 25 March and was connected by telephone to No. 20 Operations Room on 28 March; AMES 272 was set up at Trincomalee.[16] The terrain around the radar limited maximum range to 60mi (97km) and the altitude of an object affected detection range. The short time that AMES 254 had been in Colombo may not have been sufficient to train operators to identify false radar echoes produced by local conditions; real echoes may have been mistaken for false ones. The radar antenna projected "lobes" in which objects might be detected, with gaps between lobes or lobes overlapping. The trajectory of the incoming Japanese aircraft may have flown in gaps between lobes. The distance travelled by Japanese aircraft between the maximum range of AMES 254 to Ratmalana was 54mi (87km) It took about 17 minutes flying time for a Japanese Zero and five minutes for Hurricanes to take off and six to climb to interception altitude. There were only six minutes for AMES 254 to report to 20 Operations Room and for orders to be issued to pilots if they were going to avoid being caught climbing.[17]
On 9 March 1942 the Japanese Combined Fleet (Admiral Chūichi Nagumo) was ordered to protect Japanese sea communications from attack by the British army in Burma and to "sweep the Bay of Bengal clear of British naval units", ready for the occupation of the Andaman Islands and the Nicobar Islands in the eastern Indian Ocean. In February 1942, the Japanese army and navy conducted a war game to examine an invasion of Ceylon but both services were lukewarm. The army did not have the troops for an invasion and occupation; the navy was preoccupied with its operations in the Pacific.[18]
There were insufficient ships to shift an invasion force and supply a garrison against attacks by British ships, submarines and aircraft. The Prime Minister, Hideki Tojo, rejected the plan indefinitely.[19] By 16 March, the plan for an Indian Ocean raid was to depart from Staring Bay in the Celebes (now Sulawesi) in the Netherlands East Indies on 26 March, ready to attack Colombo on 5 April (C day). The Combined Fleet was based on the five aircraft carriers of the 1st Air Fleet, comprising Akagi of the 1st Carrier Squadron, Sōryū and Hiryū of the 2nd Carrier Squadron, with Shōkaku and Zuikaku of the 5th Carrier Squadron.[18]
British code-breaking
On 4 December 1941 the Japanese had altered their code JN-25B that prevented British code-breakers of the Far East Combined Bureau (FECB) from reading Japanese wireless messages. On 3 March 1942, the British began reading JN-25B messages again. By the middle of the month, decrypts revealed that the 1st Carrier Squadron and the 2nd Carrier Squadron were at Staring Bay in the Celebes, an Imperial Japanese Navy fuelling base and that the 5th Carrier Squadron was en route. Around 20 March decrypts revealed that a carrier force in Area D was going to attack DG on 2 April (C Day). On 28 March it was inferred that DG was Colombo. Japanese preparations were delayed by the late arrival of the 5th Carrier Squadron at Staring Bay on 24 March and the fleet sailed 26 March.[20]
The British air defences in Ceylon were alerted for an attack on 1 or 2 March and merchant shipping dispersed from Colombo. The Eastern Fleet sortied on 30 March to patrol 100mi (160km) south of the island. Aerial reconnaissance by Catalina flying-boats concentrated on the south-east, the right direction that the Japanese would approach but with no sightings, the Eastern Fleet retired late on 2 April toward Addu Atoll to refuel at Gan (Port T) about 600mi (970km) south-west of Ceylon. The heavy cruisers HMSCornwall and Dorsetshire sailed for Colombo and HMSHermes set out for Trincomalee to resume their commitments.[20]
Prelude
2−4 April
The deck of the Japanese aircraft carrier Akagi before the Indian Ocean raid
During the morning of 2 April, three Kawanishi H6K flying boats from Port Blair made a reconnaissance flight towards Ceylon and early on 4 April, an H6K was sent to Trincomalee, observing eight merchant ships and a destroyer in the harbour.[21] The Japanese cancelled a planned reconnaissance of Colombo harbour on 4 April by cruiser floatplanes.[22] Before dawn on 4 April, Catalina QL-A of 413 Squadron RCAF, flown by Squadron Leader Leonard Birchall, took off from Koggala to reconnoitre the southern-most patrol sector.[23]
Later in the day, the crew decided to repeat a leg that took them to the southern-most point of their patrol. At 16:00, the crew of QL-A spotted the Japanese fleet on the southern horizon, about 360nmi (670km; 410mi) south-east of Ceylon.[23] Three Zeros from Akagi, three from Zuikaku and six from Hiryū attacked the Catalina as it closed to get an accurate sighting. The radio was destroyed mid-transmission and only the sighting not the size of the fleet was received at Ceylon; several minutes after the Zeros attacked, QL-A was forced down on the sea.[24]
Squadron Leader Leonard Birchall RCAF, flew the Catalina that spotted the Japanese fleet
Zeroes strafed and sank the Catalina, the front gunner had been killed and two of the crew were shot in the water. The six survivors, including Birchall, were captured by the Japanese destroyerIsokaze. The prisoners claimed to have taken off from Colombo and this was reported to the fleet flagship Akagi late in the day; Koggala was not attacked during the raid. The prisoners denied making a sighting report but were confounded when the Japanese intercepted a signal from Colombo asking QL-A to repeat its report.[25]
Catalina FV-R from 205 Squadron, flown by Flight Lieutenant "Jock" Graham, took off at 17:45. FV-R made reports at 22:37 of a destroyer at 01°59′N82°20′E / 1.983°N 82.333°E / 1.983; 82.333, course 315 degrees, speed 20kn (37km/h; 23mph) and on 5 April at 00:45 reported six destroyers at 02°54′N82°10′E / 2.900°N 82.167°E / 2.900; 82.167, course 325 degrees, speed 21kn (39km/h; 24mph) and at 06:15 a battleship, a cruiser "and at least four other ships" (Stuart 2014) 110nmi (200km; 130mi), on a bearing of 195 degrees from Dondra Head, the southern tip of Ceylon. The Catalina was shot down by Japanese fighters about an hour and a half after making the report, with the loss of the crew.[26]
Attack on Colombo
5 April
After the report from QL-A, D'Albiac briefed his staff for a Japanese air attack around dawn; 222 Group issued Operation Order No. 43 before midnight on 4 April,
Should the enemy force maintain present reported course at a speed of 25 knots it will arrive in position approximately 150 miles from Colombo at 2100 hours G.M.T. [Greenwich Mean Time].[27]
Example of a Sea Hurricane Mk.1b
At 04:00 on 5 April the RAF and FAA squadrons were put on stand by with pilots at immediate readiness; 803 NAS scrambled six Fulmars from Ratmalana to patrol from Bentota, 35mi (56km) south of Colombo on the west coast, to Pottuvri on the south-east coast. The Navy ordered ships at Colombo and Trincomalee to scatter but at Colombo 21 merchant ships and 13 naval vessels were unable to sail due to defects and other reasons.[28]Cornwall and Dorsetshire had departed from Colombo late on 4 April to rejoin the Eastern Fleet, part of which had started sailing back to Ceylon from Port T after the QL-A report.[29]
At 05:34, Catalina BN-L of 240 Squadron, piloted by Flight Lieutenant W. Bradshaw, took off. At about 06:40, The crew saw six aircraft that looked like Fulmars at 5,000ft (1,500m) in scattered cloud, flying north in vic formation, about 100nmi (190km; 120mi) south of Ceylon. Four more aircraft were taken to be Sea Hurricanes, were also flying north. Since the aircraft were "British", Bradshaw kept radio silence. A Japanese aircraft had spotted BN-L at 06:38 and signalled soon afterwards "Sighted enemy plane. One flying boat at 346 degrees, 43 nmi [80km (50mi)] from launch point.(Stuart 2014)[27]
The Japanese aircraft carriers began flying off 91 bombers and 36 fighters shortly after 06:00 on 5 April.[30] Shortly after 06:40, Catalina BN-L spotted four Japanese aircraft flying north but identified them as Hurricanes and failed to report them. The flying boat was seen by the Japanese and Hiryū received a sighting report at 06:45. The Japanese aircraft approached Colombo from the sea to the south-east, preventing detection by coast watchers and the 803 NAS line patrol. AMES 254 and its radar also failed to detect the Japanese force. British fighter pilots waited for a scramble that, due to the lack of early warning, never came, instead they were forced to take off during the attack, at a serious tactical disadvantage.[31]
At 07:30, nine Zero fighters from Hiryū flew over the Colombo Racecourse airfield. The 14 Hurricanes of 258 Squadron took off in good order by 07:35 and climbed toward the harbour. Ten minutes later, 38 Vals from Shōkaku and Zuikaku were spotted from Ratmalana. The 14 Vals from Zuikaku attacked the airfield at 07:45 as Hurricanes from 30 Squadron were taking off in ones and twos; 21 got of the ground but four were not airborne when the first bombs fell. The commanding officer's Hurricane was damaged and crashed on take-off. Six Fulmars from 803 NAS and 806 NAS also took off from Ratmalana. The British fighters were fully occupied defending the airbase, helped by cloud cover and the first Hurricanes airborne attacked the bombers before their attack. Five Vals and a Zero were shot down and six Vals were possibly damaged for the loss of eight Hurricanes and three Fulmars but the airfield suffered little damage.[32]
Nineteen Vals from Shōkaku attacked the harbour around 07:50, sank the armed merchant cruiserHMSHector and damaged the submarine depot shipHMSLucia.[33] The Vals were intercepted by 258 Squadron shortly afterwards and the Hurricanes concentrated on the bombers, ignoring the fighter escorts. A Val was shot down and another damaged but eight Hurricanes were lost and two were badly damaged. The remaining bombers were able to attack the harbour and port unimpeded. Five Vals from Zuikaku damaged the British tanker MVSan Cirilo (8,012 GRT) and 53 Kate torpedo bombers, carrying bombs, sank the destroyer HMSTenedos, killing 33 members of the crew.[33] The bombers damaged the merchant ship SSBenledi (5,943 GRT) and hit port facilities. The Norwegian tanker MVSoli (5,834 GRT) was damaged and beached and the British freighter SSClan Murdoch (5,960 GRT) was damaged.[34] The Japanese aircraft landed on their carriers from 09:45 to 10:30.[35]
Ten Blenheims of 11 Squadron took off at 08:30 but got the wrong directions and failed to find the Japanese fleet. Catalinas based in Ceylon and Albacores from the Eastern Fleet continued to fly reconnaissance sorties during the day. At 08:40, three Zeros apiece from Hiryū, Shōkaku and Zuikaku shot down Catalina FV-R of 205 Squadron and killed the crew but not before the gunners damaged two of the Zeros from Zuikaku. Later on, three Zeros from Hiryū attacked two 827 NAS Albacores from the Eastern Fleet and shot one down, the crew being killed. Another 827 NAS Albacore was attacked by Zeros from Hiryū but escaped in cloud.[36]
Aircraft from Japanese cruisers searched the area south of Ceylon for the British ships that had not been found in port. At 11:00, No 4 spotter aircraft, from the Japanese cruiser Tone, found Dorsetshire and Cornwall south-east of the Combined Fleet and identified them as destroyers. The 5th Carrier Squadron, in reserve with its aircraft loaded with bombs for another attack on Colombo, was ordered to attack the British cruisers instead. Rearming with torpedoes took too long and the 2nd Carrier Squadron attacked with 18 Vals from Sōryū, 18 from Hiryū and 17 from Akagi.[37] At 12:50, the Vals from Soryu attacked out of the sun, from 14:40 to 14:55 and claimed 14 hits. The Vals from Hiryū commenced their attack soon after those from Sōryū and the Vals from Akagi claimed seven hits on one cruiser and eight hits on the other. Dorsetshire was bombed on its aircraft catapult, bridge, engine rooms and boiler rooms; the rudder jammed and the cruiser sank at 14:48. Cornwall was hit by 15 bombs and sank six minutes later. The ships had a combined crew complement of 1,646 men of whom 424 were killed and 1,222 men were rescued (after thirty hours in the sun, in waters inhabited by sharks) by the Australian cruiser HMSEnterprise and the Australian destroyers HMSPaladin and Panther.[38]
Aftermath
Casualties
On land, four Naval officers, 35 ratings, twelve men from Goa and Indian Lascars were killed and 37 civilians, inmates of a psychiatric hospital that was bombed, were killed. At sea the Navy suffered the loss of 424 men killed in the sinking of Dorsetshire and Cornwall.[39]
Aircraft losses
Japanese fighter pilot claims amounted to 33 fighters, with 11 probables; five were claimed by the Val crews from Shōkaku and one by a Val from Zuikaku. The real loss was 21 Hurricanes, two of which were repairable and several Hurricanes damaged. The Japanese fighter pilots claimed eight Swordfish, two probables and one Swordfish damaged, with a real loss of six. On the British side, 258 Squadron claimed four aircraft shot down, one probable and four damaged for a loss of eight Hurricanes and two badly damaged, five pilots killed and two wounded. In 30 Squadron, 14 aircraft were claimed shot down, with six probables and five aircraft damaged. The Fleet Air Arm pilots of 803 NAS and 806 NAS claimed one Japanese aircraft shot down for a loss of four Fulmars and three pilots killed and six Swordfish from 788 NAS flew into the battle while on a transit flight and were shot down.[40] Anti-aircraft gunners claimed five aircraft shot down for a total of 24 Japanese aircraft confirmed shot down, seven probables and a minimum of nine aircraft damaged. Both sides mistakenly over-claimed; a Zero from Sōryū was shot down and three from Hiryū were damaged. Five Vals from Zuikaku were shot down and six suffered damage, Shōkaku lost one Val and one was damaged. The true total was six Vals and seven damaged, one Zero shot down and three damaged and five Kates damaged.[41]
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Richards, Denis; Saunders, Hilary St. George (1975) [1954]. The Fight Avails. Official History of the Royal Air Force 1935–1945. Vol.II. London: HMSO. ISBN0-11-771593-X– via Archive Foundation.
Rohwer, Jürgen; Hümmelchen, Gerhard (2005) [1972]. Chronology of the War at Sea, 1939–1945: The Naval History of World War Two (3rd rev.ed.). London: Chatham. ISBN1-86176-257-7.
Shores, Christopher; Cull, Brian; Izawa, Yasuho (2014) [1993]. Bloody Shambles: The Defence of Sumatra to the Fall of Burma. Vol.II. London: Grub Street. ISBN978-0-94-881767-0.
Stille, Mark (2023). Japan's Indian Ocean Raid 1942: The Allies' Lowest Ebb. Campaign No. 396. Oxford: Osprey. ISBN978-1-47-285418-6.
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Further reading
Probert, Henry (1996) [1995]. The Forgotten Air Force: The Royal Air Force in the War Against Japan 1941–1945. London: Brassey's. ISBN1-85753-065-9.
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