Coron Bay on the Island of Palawan, Philipines is regarded as "the other Truk Lagoon". In 1944 task force 39, part of the US 3rd fleet, and under the command of Admiral William Hasley attacked 20 enemy ships. First aerial recconoconce had revealed only islands, however, subsiquent photo’s revealed these "islands" had moved. The Japanese had placed trees on the decks of the ships in order to disguise them. 45 minutes into the attack 18 vessels were sinking. The raid set a new record for long distance raids 350 miles. The result was, like Truk Lagoon a legacy of shipwrecks that would later delight the diving world.
The Attack on Japanese shipping in Coron Bay
It happened during the war in the Pacific in 1944; a convoy comprising 12 auxiliary ships of the Imperial Japanese Navy had been dispersed in the coastal waters around Busuanga, an island belonging to the Calamian Group in the Philippines. At least 8 ships were closely packed in Coron Bay, a beautiful place bordered by pristine beaches and countless coconut palm trees.
Between The Battle of the Philippine Sea on 19 and 20 June 1944 and The Battle of Leyte Gulf from 23 to 26 October 1944 the Japanese attempted to reinforce their forces which were occupying the Philippines. For divers, Coron's history started on 24 September 1944 when a US Navy strike force of fighters and dive bombers attacked a Japanese supply fleet of up to 24 ships at anchor in Coron Bay and around Busuanga Island.
Whether the Japanese fleet was spotted by aerial photo reconnaissance interpreters who noticed that some camouflaged ships had moved, or whether Japanese radio transmissions were intercepted is still debated. Photos taken from the air during the attack do not show any signs of camouflage netting on the ships. The consequence of detection was a surprise aerial attack by US Navy carrier based aircraft that sank the fleet at anchor.
The US Third Fleet was under the command of Admiral William F. "Bull" Halsey aboard the battleship USS New Jersey. Bull Halsey missed the battle of Midway sitting in a Pearl Harbor naval hospital with a skin rash. He had his chance to catch the Japanese navy by surprise at Coron.
Tactical control of the Third Fleet rested with the air combat genius of the Pacific Fleet, Vice Admiral Marc A. Mitscher, who was in command of Task Force 38 from the aircraft carrier USS Lexington.
Task Force 38 was engaged in the mission of naval air strikes against Japanese forces in the Philippines from 21 to 24 Sept 1944. Heavy air strikes against Japanese shipping in Manila Bay resulted in sinking 15 ships which forced the Japanese to move their remaining ships to other anchorages which they thought were out of range of US naval aircraft and land-based bombers. One of these secure anchorages was Coron Bay, only 12 to 16 hours steaming time from Manila. Many of the ships arrived in Coron Bay on the 23rd. On the morning of 24 September 1944 at 0550 a total of 96 Grumman F6F Hellcat fighter escorts and 24 Curtiss SB2C Helldiver dive bombers took off on a flight to their targets 340 miles away. The raid on Coron was a long distance carrier based air strike and would only allow the aircraft a brief time over the Japanese fleet.
At 0900 the strike force reached Busuanga Island, Palawan and found 12 large enemy ships anchored in Coron Bay and around Busuanga Island. After a 15 minute attack they left behind a carnage of burning and sinking ships.
The oiler Kamoi, other cargo ships and one destroyer tried to conceal their presence in the narrow sound between Tangat island and Lusong island which confine the bay to the east and west. West, beyond Lusong Island, the seaplane tender Akitsushima and the oiler Okikawa Maru were swinging at their anchors in the slight tidal current.
Located about 170 nautical miles southwest of Manila, Coron Bay allegedly was safe as an assembly area. The cargo ship Kyokuzan Maru and two others were anchored in a small bay on the northeast coast of Busuanga.
In the early morning of 24 September 1944, 22 American carrier-based dive bombers and 96 fighter escorts (some carrying bombs) of the Fast Carrier Task Force (TF) 38 surprisingly appeared. Without hesitation, a squadron of Curtiss Helldivers took on Akitsushima and Okikawa Maru. Although the seaplane tender was heavily armed and opened fire with all her guns, she was no match for the skilled dive bomber crews. A bomb hit the hull at the port side, causing a severe explosion. Wracked by fire and explosion from other impacts, Akitsushima went down in the passage between Lajo and Manglet Island. Fully laden with fuel oil, Okikawa Maru was fatally bombed and caught fire. However, she remained afloat and slowly began to drift to the north. She was finally sank on by a second air attack on 9 October.
Meanwhile, the second bomber squadron had teamed up to sink the other ships. Ten dive bombers took on Olympia Maru. Three American pilots completed runs on the ship. It stood little chance to survive after the fourth plane hit the midships section causing the engine to stop. Finally, Olympia Maru sank from the stern, becoming a graveyard for 19 crew members. In rapid succession, the remaining ships faced dive bombing attacks by the US Navy bombers. Kogyo Maru went down with no less than 39 seamen.
Considerably armed with a variety of flak guns, Irako responded with ferocity. But even she was annihilated and sent to the bottom. The others suffered a similar fate. The final casualty of the morning-long slugfest was the Kyokuzan Maru, which had erroneously felt secure on her natural anchorage far to the northeast. She and two other ships were attacked by planes from the USS Lexington. Damage and a fire was reported on one of the ships. The Kyokuzan Maru was scuttled by the Japanese. Badly damaged, the oiler Kamoi was able to escape and to make it back to Hong Kong.
The Expedition
Eight divers from the UK dived the Japanese shipwrecks in Coron Bay, Philippines for 12 days in May 2004. Hosted by Discovery Divers the group made two dives daily on the Japanese fleet which lay at depths of between 25 and 45m.
The team used a variety of dive equipment ranging from single cylinders, twin sets and KISS rebreathers. Most dive times were between 1 hour and 1 1/2 hours long which included up to 40 minutes of decompression. The open circuit divers used 30% or 32% nitrox.
Gunter at Discovery Divers sourced the rebreather scrubber from Manila and we changed the scruber daily - approximately 2 1/2 hours diving. We used 3l cylinders on the rebreathers which we brought with us from the UK. Top O2 pressure was around 110bar and we filled this each night.
Water visibility ranged from 5m to 20m and was generally around 10m on the wrecks in Coron Bay. The visibility to the North of Coron, on the Kyokuzan Maru is considerably beter when we dived it, being around 20m to 25m.
Most wrecks are easy to penetrate. Most of the cargo ships have empty holds and some salvage has been carried on out many wrecks to remove the engines. The Akitsushima is a warship and has an interesting engine room and the shell hoist for the 5 inch gun can be seen below decks, complete with one shell. The Irako Maru is also a very interesting penetration dive, although is a little deaper so should be treated with caution.
I would thoroughly recommend Discovery Divers. The resort was comfortable, the food good and the service excelent. The staff went out of their way to assist us in doing everything we wanted.
Akitsushima
