'MS' (ii) was the designation of Allied convoys (together with a numerical suffix) plying the route from Melbourne, Australia, to Singapore with reinforcements, supplies and equipment for the British-led forces facing the Japanese 'E' (i) invasion, or from Ratai Bay, Sumatra, to Singapore, or from Fremantle, Australia to Colombo, Ceylon (January/March 1942).

The first of the convoys was MS.1 of 10/31 January 1941 with 12 merchant ships, five of them British (5,609-ton Anglo Indian, 8,917-ton City of Manchester, 4,799-ton Derrymore, 3,533-ton Gorgon and 6,225-ton Peisander), three Dutch (5,412-ton Enggano, 9,250-ton Java and 6,181-ton Phrontis), one Norwegian (9,468-ton Pan Europe) and Tjikandi, Tjikarang and War Sirdar.

The last of the four convoys was MS.5 of 22 February/5 March 1942 with two British merchant vessels (10,346-ton Duntroon and 9,424-ton Katoomba), two US merchant vessels (6,021-ton Sea Witch carrying 27 crated aircraft and 14,812-ton Willard A. Holbrook) as well as the 11,060-ton US seaplane tender Langley, which was badly damaged and then sunk by other US warships on 27 February.

Langley was of considerable historical interest as the ship had been the US Navy’s first aircraft carrier when converted in 1920 from the collier Jupiter, and had also been the US Navy’s first electrically propelled ship. The ship was named for Samuel Pierpont Langley, a US aviation pioneer.

Jupiter was converted into the first US aircraft carrier at the Navy Yard of Norfolk, Virginia, for the purpose of conducting experiments in the new idea of seaborne aviation, and was recommissioned on 20 March 1922. As the first US carrier, Langley featured in a number of important events. On 17 October 1922, Lieutenant Virgil C. Griffin flew the first aeroplane, a Vought VE-7, from her flight deck, thereby inaugurating the US Navy’s carrierborne air power era. Nine days later, with Langley under way, Lieutenant Commander Godfrey de Courcelles Chevalier made the first US deck landing in an Aeromarine 39B. On 18 November, Commander Whiting was the first aviator to be catapulted from a carrier’s deck.

By 15 January 1923, Langley had begun flight operations and tests in the Caribbean Sea for carrier landings. In June, she steamed to Washington, DC, to give a demonstration at a flying exhibition. Te ship reached Norfolk on 13 June, and began training along the Atlantic coast and Caribbean in a programme that lasted to the end of the year. In 1924, Langley was used in more manoeuvres and exhibitions, and spent the summer at Norfolk for repairs and alterations. The ship departed for the US west coast late in the year and reached San Diego, California, on 29 November to join the Pacific Battle Fleet. For the next 12 years, the ship operated off the California coast and Hawaii in training fleet units, experiments, pilot training, and the exploration of fleet tactical problems.

On 25 October 1936 Langley entered Mare Island Navy Yard, California, for overhaul and conversion into a seaplane tender. The conversion was completed on 26 February 1937, and the ship was then assigned to the Aircraft Scouting Force and began tender operations from Seattle in Washington state, Sitka in Alaska, Pearl Harbor in Hawaii, and San Diego in California. The ship was briefly deployed with the Atlantic Fleet from 1 February to 10 July 1939, and then steamed to assume duties with the Pacific Fleet at Manila, which she reached on 24 September.

On the US entry into World War II in December 1941, Langley was anchored off Cavite in the Philippine islands. On 8 December, following the Japanese 'M' invasion of the Philippine islands, the ship departed for Balikpapan on the island of Borneo in the Dutch East Indies. As Japanese advances continued, Langley departed for Australia, arriving in Darwin on 1 January 1942, after which the ship became part of the ABDACOM naval forces. Until 11 January, Langley assisted the Royal Australian Air Force in running anti-submarine patrols out of Darwin. The ship then travelled to Fremantle, Western Australia, to collect aircraft and transport them to South-East Asia.

Carrying 32 Curtiss P-40 fighters of the Far East Air Force’s 13^th Pursuit Squadron (Provisional), Langley departed Fremantle on 22 February as part of the MS.5 convoy, which the ship left five days later to deliver the embarked aircraft to Tjilatjap (Cilacap) on the island of Java.

Early on 27 February Langley made rendezvous with an escort comprising the US destroyers Whipple and Edsall. At 11.40, about 75 miles (120 km) to the south of Tjilatjap, nine Aichi D3A1 'Val' dive-bombers of the Imperial Japanese navy air force’s 21^st and 23^rd Air Flotillas attacked the ship. The first and second Japanese efforts were unsuccessful, but in the third Langley received five hits and lost 16 men killed. The ship burst into flame, steering was impaired, and the ship developed a 10° list to port. Unable to negotiate the narrow mouth of Tjilatjap harbour, Langley went dead in the water as the engine room flooded, and at 13.32 the order was given for the ship to be abandoned. The escorting destroyers fired nine 4-in (102-mm) shells and two torpedoes into Langley, to ensure that the hulk did not fall into Japanese hands, and the vessel sank.

After being transferred to the fleet oiler Pecos, many of the crew were lost when Pecos was sunk on 1 March while en route to Australia. Some 31 of the 33 pilots assigned to the 13^th Pursuit Squadron were lost with Edsall when this destroyer was sunk on the same day while responding to the distress calls of Pecos.