Pacific War 11 – Indian Ocean Raid

Pacific War 11 – Indian Ocean Raid

Japanese advance continued on unrelenting. And while Nimitz’s carriers had shown that the further southward advance be connected with significant risks, there was absolutely no resistance in the west. Japanese ships and fleet formations raided deep into the Indian Ocean, not encountering any serious opposition. In order to avoid confusion with German submarines and auxilliary cruisers that were also operating there, 70° longitude was chosen as an operational border, placing almost entirety of India within the Japanese operational zone.

To their zone the Japanese sent a large number of submarines, and then decided to attack Ceylon. The fall of Ceylon would sever trade routes with Australia and New Zealand. Its capture would allow Japan to raid India and Middle-East. In Britain, such an event would certainly topple Churchill’s shaken coalition government. But the best that could be done was to send Admiral Sommerville to take command. He arrived to Colombo on 24th of March.

For this task, a strong squadron left port of Kendari on Celebes on 26th March in order to strike Ceylon at 4th of April. The strike had originally been planned for 1st of April, but departure had been postponed until intentions of the US carrier force spotted near Wake island on March 10th had become clear. Squadron was commanded by admiral Nagumo and consisted of 5 aircraft carriers, 3 fast battleships, 3 cruisers and 9 destroyers. Second squadron under admiral Kurita was also deployed independently into the Indian Ocean. This squadron consisted of an aircraft carrier, 6 cruisers and several destroyers. Far behind them was a supply group of 6 tankers and 3 destroyers.

Two days after the Japanese squadrons had sailed, Admiral Somerville, commander of the British fleet in the Indian Ocean, received message from Admiralty stating that the Japanese were planning to attack Ceylon. Sommervile had two old battleships, small aircraft carrier Hermes of 10 000 tons and 20 aircraft, 6 British and 2 Dutch cruisers, as well as a larger number of destroyers and submarines. Unmodernised R-class battleships Ramillies and Royal Sovereign were soon joined by Warspite. Some time later, remaining R-class battleships, Resolution and Revenge as well as Illustrious-class carrier Indomitable and eight destroyers joined the force as well. But the Royal Navy had no experience in such large fleet operations. Since the start of the war, never had two fleet carriers operated in concert, and a force of four battleships had also been a rare luxury.

Old British ships were in various states of disrepair, and Somerville noted that “there is not a ship at present that approaches what I should call a proper standard of fighting efficiency”. Most of his ships were slow, and none were designed for operations in tropical conditions. Two modern Illustrious-class carriers presented majority of the available carrier force, while smaller Hermes was still useful as an escort. But many pilots were untrained and untested, flying aircraft that were not capable of matching Japanese carrier-based aircraft. Handful of Martlets and Sea Hurricanes aboard the two fleet carriers would certainly make no difference.

Four R-class battleships had the same 15 inch guns as Warspite did, but they were unmodernized and capable of only 18 knots. Somerville’s 6-inch cruisers were antiquated vessels and some had not even been modernized, while his 8-inch heavy cruisers of the County class had protection more fitting a light cruiser.

British intelligence estimated the Japanese force to consist of two or more carriers, battleships of the Kongo class, several eight-inch cruisers, two six-inch cruisers and accompanying destroyers. Estimated time of arrival was 31st of March. As fool moon was forecast for the 1st of April, Somerville was convinced the attack would be launched before dawn that day.

Having received news from the Admiralty, Somerville searched several days for the enemy ships. But he found nothing, as the Japanese squadron was still far away. Nagumo had in fact modified his plans to attack on the morning of 5th April: the Easter Sunday, when he expected many defenders to be attending the church.

Having spent most of their fuel, British ships withdrew to Addu Atoll at Maledive Islands, some 600 miles south-west of Ceylon, on 4th April 1942. They could not have stayed much longer in any case: Operation IRONCLAD, the invasion of Diego Suarez in Madagascar. This was necessary to prevent the Vichy French from handing over the port facilities to the Japanese the way they had in the French Indochina. Because of this, Hermes and Vampire were dispatched to Trincomalee to undergo boiler cleaning.

While Addu Atoll lacked anti-submarine and anti-aircraft defenses, it did allow the Eastern Fleet something of a safe anchorage, as well as a chance to pick the time and location of the fight. Somerville mistakenly believed that the Japanese, much like the Italians and the US, had no skill at night fighting. His two-seat Fulmar fighters could be operated at night, while Albacore torpedo-bombers were fitted with the latest airborne surface-search radars. He hoped to utilize this to his advantage. But overall, his strategy was to keep his fleet in being and to avoid losses by attrition. This he hoped to do “by keeping the fleet at sea as much as possible; to avoid it being caught in harbour; to avoid a daylight action whilst seeking to deliver night torpedo attacks; and not to undertake operations that do not give reasonable prospects of success.”. He knew he had a little chance of stopping the Japanese in a head-on confrontation, especially since neither Formidable nor Indomitable had had time to work up their pilots. Japanese objective meanwhile was to draw the British Eastern Fleet into battle and destroy it.

By 5th April, Dorsetshire and Cornwall had again taken up their berths at Colombo. British ships spent most of the day refueling and resupplying, while scout aircraft were cruising all over the Indian Ocean. On afternoon of the same day a scout detected Japanese squadron 400 miles southeast of Ceylon, and British ships prepared for action. Sommerville took the ships that had finished resupplying, while the rest were to follow shortly after. Cornwall and Dorsetshire set sail to meet up with Somerville’s Force A at the prearranged staging point 250 miles south of Ceylon. 48 merchant ships scattered to the west and northwest, while further 21 ship remained in harbor, unable to sail. At midnight, the remaining fast ships of Somerville’s fleet set out from Addu Atoll and made their way eastward.

Bases on Ceylon had been warned about the impending attack. Main harbor of the island was Colombo, but other harbors were also full of ships which had sheltered there. But despite the sufficient forewarning – the attack happened only the next day – there were still 29 cargo ships and several warships present in the harbor. Island’s 35 fighter aircraft put up stiff resistance, but the Japanese aircraft broke through, shooting down two thirds of British fighters in the process. Japanese bombers attacked Colombo, sinking a destroyer and an auxilliary cruiser. Having learned from the attack on Pearl Harbor, the Japanese also devastated workshops and storage facilities. Ten Blenheims which had escaped the attack attempted to attack the Japanese fleet, but failed to find it.

Short time after the attack Japanese scout reported having noticed two heavy cruisers. These were heavy cruisers Cornwall and Dorsetshire, which were sailling full speed west to join Admiral Sommerville’s squadron. It was not long before Japanese bombers appeared overhead. While the cruisers had noticed them, and reported the bombers’ location to Admiral Sommerville, they were still about an hour away from the range of British carriers’ Combat Air Patrol. Japanese bombers could calmly position themselves straight ahead of the cruisers, in an area where old cruisers’ anti-aircraft guns did not cover. In just eight minutes of attack, both cruisers disappeared under the sea, taking with them to death over 400 men of their crews.

HMS Cornwall sinking

In order to avoid sharing similar fate, Sommerville kept his ships outside the range of Japanese aircraft during the day. His goal was to use the night to close in and force a short-range combat after an initial Albacore strike. But despite two fleets coming to within 180 miles, neither noticed the other. As attempt at night attack failed, Sommerville retreated overnight to Maledives.

He had decided to abandon his attempts to intercept the Japanese fleet. His carriers stood no chance against the numbers of Japanese aircraft that had been reported, and the loss of Cornwall and Dorsetshire had put a serious dent into his fast force. Instead, Somerville would ensure a “fleet in being” by sending Force B westwards, to the Kilindini naval base near Mombassa. Force A would be based in Bombay, from where it could protect the convoys operating in the Indian Ocean while still being able to evade attack from enemy carrier force.

Four days after the attack on Colombo the Japanese aircraft attacked Trincomalee, the second largest port on Ceylon. Aim was to try and catch the main British fleet in port: Nagumo knew that British ships had only limited endurance, and the Japanese were unaware of the secret anchorage at Addu Atoll. Thanks to a timely sighting by a Catalina, this attack too failed to surprise the British: their fighters were already in the air, and most ships had left the port. Only one merchant ship was unable to set sail, and old 15-inch gun monitor Erebus was left in port to complement the anti-aircraft defenses. There would have been no losses at all if some ships had not returned too early, believing there would be no attack. Because of this, the British ended up losing a light aircraft carrier Hermes, her escorting destroyer, a corvette, one auxiliary warship, and one transport ship.

British downed 5 Japanese aircraft in air combat, losing 8 fighters, and this despite having only 16 Hurricanes against 41 Zeros. Hermes had had no aircraft onboard, as all her aircraft had been sent groundside. Captain Onslow attempted to get under air cover, but even intervention of six Fulmars failed to save the carrier which was quickly hit, with bombs penetrating unarmored deck. More Fulmars were sent, but before they could arrive, a repeat Japanese attack landed more hits on the carrier, killing captain Onslow. Hermes sank at 10.55 AM. Fulmars did however manage to interfere with Japanese attacks on other ships.

A squadron of British high-altitude bombers came upon Japanese carrier Akagi just as she was recovering the aircraft. This was the first time a Japanese carrier strike force had come under attack. But high-altitude bombers were never good against ships, and this had again shown itself as all the bombs missed. The only thing bombs caused was some confusion on the carrier, but despite this, five Blenheims were shot down and other four damaged.

These attacks meant that all of the British naval bases and workshops in the Japanese zone of Indian Ocean had been disabled. But during the operation, the Japanese had lost over 50 aircraft with experienced crews, which had significant effect on later operations. At the same time, thanks to Somerville’s prudence, they had failed to cause significant damage to the British Eastern Fleet.

While this was going on, Admiral Ozawa’s fast squadron was sinking merchant ships along the coasts of India. Within a week from attack on Ceylon, Ozawa’s squadron had sunk 100 000 tons of merchant shipping, while submarines along the western coast of India had sunk further 40 000 tons. Japanese will be returning home just in time for American performance.

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