Frederick Reefs

General description

The Frederick Reefs are a remote cluster of reefs located south of the Great Barrier Reef, about 540 kilometers directly east of Mackay, Queensland, and 450 kilometers northeast of Gladstone. They belong to the southern Coral Sea reefs and sit in deep ocean waters beyond the Coral Sea Shelf. The complex is 175 kilometers east of the Swains Reefs, roughly 95 kilometers northeast of the Saumarez Reefs, and 120 kilometers west of the northwestern edge of Kenn Reefs.

These reefs enclose a semi-enclosed lagoon called Anchorage Sound, which is open only on its northern side. The only permanent land is Observatory Cay, at 21°02'S, 154°23'E, standing about 1.8 meters above sea level. A boat channel from the northeast allows possible landing on its northern side. During heavy gales, surf can wash over the cay.

The sand spit’s location can shift; in 1983, the cay was reported about 750 meters west of its mapped position. Besides Observatory Cay, the reef complex has at least four or five other sand cays on the southern reef that stay above water at high tide. A solitary leaning rock, 1.2 meters high, sits on the western edge of the southern reef, 2.4 kilometers west-northwest of Observatory Cay. From the cay, the southern reef runs north and northeast for 6.2 kilometers.

Danger Ridge, at 21°00'S, 154°21'E, is a narrow ridge linking the western end of Observation Cay to Ridge Rock. North Reef Extreme lies north of Observatory Cay, with its southern end about 3 kilometers from the southern edge of the Observatory Cay reef; it is roughly 2.7 kilometers long and 900 meters wide. A small cay is located 900 meters south of the Frederick Reef Light, which stands at the northeastern tip of the reef, the only part that stays permanently above water. The light can be reached only by boat and has a nominal range of 20 kilometers.

History

The reefs were discovered in 1812 by the ship Frederick. On 11 June 1825, the Royal Charlotte, which had arrived in Sydney from England on 29 April with convicts and later took on detachments of the 20th, 46th, and 49th Regiments for transport to India via Batavia, ran aground on Frederick Reefs. The masts were cut away to steady the ship while crew and soldiers moved ashore with water and provisions before she sank; only two lives were lost. A party took the surviving longboat to Moreton Bay, arriving in July, leading to the dispatch of the brig Amity to collect survivors.

The wreck was discovered in January 2012. On 4 November 1966, the United States submarine USS Tiru, which had departed Brisbane for Subic Bay on 2 November, ran aground on Frederick Reef. After two days of unsuccessful attempts to back off under its own power, the Australian destroyer HMAS Vendetta and civilian tugboat Carlock arrived on 6 November to assist. The submarine was towed to Brisbane, drydocked for emergency repairs and damage assessment.

Following temporary repairs to its sonar dome, outer hull, and keel, the submarine proceeded to the United States Naval Ship Repair Facility in Yokosuka, Japan, calling at Guam en route, and arrived on 29 November for drydock availability. On 23 April 1986, the India-flagged bulk carrier Jhansi Ki Rani departed Newcastle, New South Wales for Japan with 74,000 tonnes of coal. The planned route took it 10 nmi east of Frederick Reef on 26 April. During the Second Officer's watch, constant rain reduced visibility from 10 km to 3 km.

At 1515, a radar object 17.5 nmi away was assumed to be the Frederick Reefs Lighthouse but was actually another ship, MV Fort Resolution. Two hours later, another radar echo 9 nmi away became obscured by rain clutter and vanished. The Master arrived on the bridge at 1725 to confirm progress and prepare for passing the reefs. Shortly after, the Chief Officer and lookout reported a white line close ahead—waves breaking over the reef edge.

The ship was ordered hard to port but did not swing far enough to clear the southern edge, running aground 5.7 nmi from the tower. Engines were stopped, then put full astern at 1736; after almost two hours, attempts ceased. Some oil pollution was observed from a damaged forward oil fuel deep tank. The vessel was refloated on 4 May, anchored for inspection, then towed to Singapore for repairs and put up for auction with its coal cargo.